| Step | Hyp | Ref | Expression | 
						
							| 1 |  | simpl3 | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐵  ∈  ℕ ) | 
						
							| 2 | 1 | nnred | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐵  ∈  ℝ ) | 
						
							| 3 | 2 | resqcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐵 ↑ 2 )  ∈  ℝ ) | 
						
							| 4 | 2 | sqge0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  ≤  ( 𝐵 ↑ 2 ) ) | 
						
							| 5 | 3 4 | absidd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( 𝐵 ↑ 2 ) )  =  ( 𝐵 ↑ 2 ) ) | 
						
							| 6 | 5 | eqcomd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐵 ↑ 2 )  =  ( abs ‘ ( 𝐵 ↑ 2 ) ) ) | 
						
							| 7 | 6 | oveq2d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) )  /  ( 𝐵 ↑ 2 ) )  =  ( ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) )  /  ( abs ‘ ( 𝐵 ↑ 2 ) ) ) ) | 
						
							| 8 |  | simpl2 | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐴  ∈  ℕ ) | 
						
							| 9 | 8 | nncnd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐴  ∈  ℂ ) | 
						
							| 10 | 9 | sqcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐴 ↑ 2 )  ∈  ℂ ) | 
						
							| 11 |  | simpl1 | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐷  ∈  ℕ ) | 
						
							| 12 | 11 | nncnd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐷  ∈  ℂ ) | 
						
							| 13 | 1 | nncnd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐵  ∈  ℂ ) | 
						
							| 14 | 13 | sqcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐵 ↑ 2 )  ∈  ℂ ) | 
						
							| 15 | 12 14 | mulcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐷  ·  ( 𝐵 ↑ 2 ) )  ∈  ℂ ) | 
						
							| 16 | 10 15 | subcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) )  ∈  ℂ ) | 
						
							| 17 | 1 | nnne0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐵  ≠  0 ) | 
						
							| 18 |  | sqne0 | ⊢ ( 𝐵  ∈  ℂ  →  ( ( 𝐵 ↑ 2 )  ≠  0  ↔  𝐵  ≠  0 ) ) | 
						
							| 19 | 18 | biimpar | ⊢ ( ( 𝐵  ∈  ℂ  ∧  𝐵  ≠  0 )  →  ( 𝐵 ↑ 2 )  ≠  0 ) | 
						
							| 20 | 13 17 19 | syl2anc | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐵 ↑ 2 )  ≠  0 ) | 
						
							| 21 | 16 14 20 | absdivd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) )  /  ( 𝐵 ↑ 2 ) ) )  =  ( ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) )  /  ( abs ‘ ( 𝐵 ↑ 2 ) ) ) ) | 
						
							| 22 | 7 21 | eqtr4d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) )  /  ( 𝐵 ↑ 2 ) )  =  ( abs ‘ ( ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) )  /  ( 𝐵 ↑ 2 ) ) ) ) | 
						
							| 23 | 22 | oveq2d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) )  /  ( 𝐵 ↑ 2 ) ) )  =  ( ( 𝐵 ↑ 2 )  ·  ( abs ‘ ( ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) )  /  ( 𝐵 ↑ 2 ) ) ) ) ) | 
						
							| 24 | 16 | abscld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) )  ∈  ℝ ) | 
						
							| 25 | 24 | recnd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) )  ∈  ℂ ) | 
						
							| 26 | 25 14 20 | divcan2d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) )  /  ( 𝐵 ↑ 2 ) ) )  =  ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) ) ) | 
						
							| 27 | 10 15 14 20 | divsubdird | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) )  /  ( 𝐵 ↑ 2 ) )  =  ( ( ( 𝐴 ↑ 2 )  /  ( 𝐵 ↑ 2 ) )  −  ( ( 𝐷  ·  ( 𝐵 ↑ 2 ) )  /  ( 𝐵 ↑ 2 ) ) ) ) | 
						
							| 28 | 9 13 17 | sqdivd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐴  /  𝐵 ) ↑ 2 )  =  ( ( 𝐴 ↑ 2 )  /  ( 𝐵 ↑ 2 ) ) ) | 
						
							| 29 | 28 | eqcomd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐴 ↑ 2 )  /  ( 𝐵 ↑ 2 ) )  =  ( ( 𝐴  /  𝐵 ) ↑ 2 ) ) | 
						
							| 30 | 11 | nnred | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐷  ∈  ℝ ) | 
						
							| 31 | 11 | nnnn0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐷  ∈  ℕ0 ) | 
						
							| 32 | 31 | nn0ge0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  ≤  𝐷 ) | 
						
							| 33 |  | remsqsqrt | ⊢ ( ( 𝐷  ∈  ℝ  ∧  0  ≤  𝐷 )  →  ( ( √ ‘ 𝐷 )  ·  ( √ ‘ 𝐷 ) )  =  𝐷 ) | 
						
							| 34 | 30 32 33 | syl2anc | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( √ ‘ 𝐷 )  ·  ( √ ‘ 𝐷 ) )  =  𝐷 ) | 
						
							| 35 | 30 32 | resqrtcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( √ ‘ 𝐷 )  ∈  ℝ ) | 
						
							| 36 | 35 | recnd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( √ ‘ 𝐷 )  ∈  ℂ ) | 
						
							| 37 | 36 | sqvald | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( √ ‘ 𝐷 ) ↑ 2 )  =  ( ( √ ‘ 𝐷 )  ·  ( √ ‘ 𝐷 ) ) ) | 
						
							| 38 | 12 14 20 | divcan4d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐷  ·  ( 𝐵 ↑ 2 ) )  /  ( 𝐵 ↑ 2 ) )  =  𝐷 ) | 
						
							| 39 | 34 37 38 | 3eqtr4rd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐷  ·  ( 𝐵 ↑ 2 ) )  /  ( 𝐵 ↑ 2 ) )  =  ( ( √ ‘ 𝐷 ) ↑ 2 ) ) | 
						
							| 40 | 29 39 | oveq12d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( 𝐴 ↑ 2 )  /  ( 𝐵 ↑ 2 ) )  −  ( ( 𝐷  ·  ( 𝐵 ↑ 2 ) )  /  ( 𝐵 ↑ 2 ) ) )  =  ( ( ( 𝐴  /  𝐵 ) ↑ 2 )  −  ( ( √ ‘ 𝐷 ) ↑ 2 ) ) ) | 
						
							| 41 | 9 13 17 | divcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐴  /  𝐵 )  ∈  ℂ ) | 
						
							| 42 |  | subsq | ⊢ ( ( ( 𝐴  /  𝐵 )  ∈  ℂ  ∧  ( √ ‘ 𝐷 )  ∈  ℂ )  →  ( ( ( 𝐴  /  𝐵 ) ↑ 2 )  −  ( ( √ ‘ 𝐷 ) ↑ 2 ) )  =  ( ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 43 | 41 36 42 | syl2anc | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( 𝐴  /  𝐵 ) ↑ 2 )  −  ( ( √ ‘ 𝐷 ) ↑ 2 ) )  =  ( ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 44 | 41 36 | addcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  ∈  ℂ ) | 
						
							| 45 | 8 | nnred | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  𝐴  ∈  ℝ ) | 
						
							| 46 | 45 1 | nndivred | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐴  /  𝐵 )  ∈  ℝ ) | 
						
							| 47 | 46 35 | resubcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ∈  ℝ ) | 
						
							| 48 | 47 | recnd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ∈  ℂ ) | 
						
							| 49 | 44 48 | mulcomd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  =  ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 50 | 43 49 | eqtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( 𝐴  /  𝐵 ) ↑ 2 )  −  ( ( √ ‘ 𝐷 ) ↑ 2 ) )  =  ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 51 | 27 40 50 | 3eqtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) )  /  ( 𝐵 ↑ 2 ) )  =  ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 52 | 51 | fveq2d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) )  /  ( 𝐵 ↑ 2 ) ) )  =  ( abs ‘ ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) | 
						
							| 53 | 52 | oveq2d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( abs ‘ ( ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) )  /  ( 𝐵 ↑ 2 ) ) ) )  =  ( ( 𝐵 ↑ 2 )  ·  ( abs ‘ ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) ) | 
						
							| 54 | 23 26 53 | 3eqtr3d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) )  =  ( ( 𝐵 ↑ 2 )  ·  ( abs ‘ ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) ) | 
						
							| 55 | 48 44 | absmuld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  =  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) | 
						
							| 56 | 55 | oveq2d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( abs ‘ ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  =  ( ( 𝐵 ↑ 2 )  ·  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) ) | 
						
							| 57 | 48 | abscld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ∈  ℝ ) | 
						
							| 58 | 44 | abscld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) )  ∈  ℝ ) | 
						
							| 59 | 57 58 | remulcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  ∈  ℝ ) | 
						
							| 60 | 3 59 | remulcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  ∈  ℝ ) | 
						
							| 61 |  | 2nn0 | ⊢ 2  ∈  ℕ0 | 
						
							| 62 | 61 | nn0negzi | ⊢ - 2  ∈  ℤ | 
						
							| 63 | 62 | a1i | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  - 2  ∈  ℤ ) | 
						
							| 64 | 2 17 63 | reexpclzd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐵 ↑ - 2 )  ∈  ℝ ) | 
						
							| 65 | 64 58 | remulcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  ∈  ℝ ) | 
						
							| 66 | 3 65 | remulcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  ∈  ℝ ) | 
						
							| 67 |  | 1red | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  1  ∈  ℝ ) | 
						
							| 68 |  | 2re | ⊢ 2  ∈  ℝ | 
						
							| 69 | 68 | a1i | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  2  ∈  ℝ ) | 
						
							| 70 | 69 35 | remulcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 2  ·  ( √ ‘ 𝐷 ) )  ∈  ℝ ) | 
						
							| 71 | 67 70 | readdcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 1  +  ( 2  ·  ( √ ‘ 𝐷 ) ) )  ∈  ℝ ) | 
						
							| 72 |  | simpr | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) ) | 
						
							| 73 | 8 | nngt0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  <  𝐴 ) | 
						
							| 74 | 1 | nngt0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  <  𝐵 ) | 
						
							| 75 | 45 2 73 74 | divgt0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  <  ( 𝐴  /  𝐵 ) ) | 
						
							| 76 | 11 | nngt0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  <  𝐷 ) | 
						
							| 77 |  | sqrtgt0 | ⊢ ( ( 𝐷  ∈  ℝ  ∧  0  <  𝐷 )  →  0  <  ( √ ‘ 𝐷 ) ) | 
						
							| 78 | 30 76 77 | syl2anc | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  <  ( √ ‘ 𝐷 ) ) | 
						
							| 79 | 46 35 75 78 | addgt0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  <  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) | 
						
							| 80 | 79 | gt0ne0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  ≠  0 ) | 
						
							| 81 |  | absgt0 | ⊢ ( ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  ∈  ℂ  →  ( ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  ≠  0  ↔  0  <  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) | 
						
							| 82 | 81 | biimpa | ⊢ ( ( ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  ∈  ℂ  ∧  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  ≠  0 )  →  0  <  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 83 | 44 80 82 | syl2anc | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  <  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 84 |  | ltmul1 | ⊢ ( ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ∈  ℝ  ∧  ( 𝐵 ↑ - 2 )  ∈  ℝ  ∧  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) )  ∈  ℝ  ∧  0  <  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  →  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 )  ↔  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  <  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) ) | 
						
							| 85 | 57 64 58 83 84 | syl112anc | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 )  ↔  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  <  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) ) | 
						
							| 86 | 72 85 | mpbid | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  <  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) | 
						
							| 87 | 2 17 | sqgt0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  <  ( 𝐵 ↑ 2 ) ) | 
						
							| 88 |  | ltmul2 | ⊢ ( ( ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  ∈  ℝ  ∧  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  ∈  ℝ  ∧  ( ( 𝐵 ↑ 2 )  ∈  ℝ  ∧  0  <  ( 𝐵 ↑ 2 ) ) )  →  ( ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  <  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  ↔  ( ( 𝐵 ↑ 2 )  ·  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  <  ( ( 𝐵 ↑ 2 )  ·  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) ) ) | 
						
							| 89 | 59 65 3 87 88 | syl112anc | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  <  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  ↔  ( ( 𝐵 ↑ 2 )  ·  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  <  ( ( 𝐵 ↑ 2 )  ·  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) ) ) | 
						
							| 90 | 86 89 | mpbid | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  <  ( ( 𝐵 ↑ 2 )  ·  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) ) | 
						
							| 91 | 13 17 63 | expclzd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐵 ↑ - 2 )  ∈  ℂ ) | 
						
							| 92 | 58 | recnd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) )  ∈  ℂ ) | 
						
							| 93 |  | mulass | ⊢ ( ( ( 𝐵 ↑ 2 )  ∈  ℂ  ∧  ( 𝐵 ↑ - 2 )  ∈  ℂ  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) )  ∈  ℂ )  →  ( ( ( 𝐵 ↑ 2 )  ·  ( 𝐵 ↑ - 2 ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  =  ( ( 𝐵 ↑ 2 )  ·  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) ) | 
						
							| 94 | 93 | eqcomd | ⊢ ( ( ( 𝐵 ↑ 2 )  ∈  ℂ  ∧  ( 𝐵 ↑ - 2 )  ∈  ℂ  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) )  ∈  ℂ )  →  ( ( 𝐵 ↑ 2 )  ·  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  =  ( ( ( 𝐵 ↑ 2 )  ·  ( 𝐵 ↑ - 2 ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) | 
						
							| 95 | 14 91 92 94 | syl3anc | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  =  ( ( ( 𝐵 ↑ 2 )  ·  ( 𝐵 ↑ - 2 ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) | 
						
							| 96 |  | expneg | ⊢ ( ( 𝐵  ∈  ℂ  ∧  2  ∈  ℕ0 )  →  ( 𝐵 ↑ - 2 )  =  ( 1  /  ( 𝐵 ↑ 2 ) ) ) | 
						
							| 97 | 13 61 96 | sylancl | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐵 ↑ - 2 )  =  ( 1  /  ( 𝐵 ↑ 2 ) ) ) | 
						
							| 98 | 97 | oveq2d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( 𝐵 ↑ - 2 ) )  =  ( ( 𝐵 ↑ 2 )  ·  ( 1  /  ( 𝐵 ↑ 2 ) ) ) ) | 
						
							| 99 | 14 20 | recidd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( 1  /  ( 𝐵 ↑ 2 ) ) )  =  1 ) | 
						
							| 100 | 98 99 | eqtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( 𝐵 ↑ - 2 ) )  =  1 ) | 
						
							| 101 | 100 | oveq1d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( 𝐵 ↑ 2 )  ·  ( 𝐵 ↑ - 2 ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  =  ( 1  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) ) | 
						
							| 102 | 92 | mullidd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 1  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) )  =  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 103 | 95 101 102 | 3eqtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  =  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 104 | 41 36 | addcomd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  =  ( ( √ ‘ 𝐷 )  +  ( 𝐴  /  𝐵 ) ) ) | 
						
							| 105 |  | ppncan | ⊢ ( ( ( √ ‘ 𝐷 )  ∈  ℂ  ∧  ( √ ‘ 𝐷 )  ∈  ℂ  ∧  ( 𝐴  /  𝐵 )  ∈  ℂ )  →  ( ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) )  +  ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  =  ( ( √ ‘ 𝐷 )  +  ( 𝐴  /  𝐵 ) ) ) | 
						
							| 106 | 105 | eqcomd | ⊢ ( ( ( √ ‘ 𝐷 )  ∈  ℂ  ∧  ( √ ‘ 𝐷 )  ∈  ℂ  ∧  ( 𝐴  /  𝐵 )  ∈  ℂ )  →  ( ( √ ‘ 𝐷 )  +  ( 𝐴  /  𝐵 ) )  =  ( ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) )  +  ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 107 | 36 36 41 106 | syl3anc | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( √ ‘ 𝐷 )  +  ( 𝐴  /  𝐵 ) )  =  ( ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) )  +  ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 108 | 36 36 | addcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) )  ∈  ℂ ) | 
						
							| 109 | 108 48 | addcomd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) )  +  ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  =  ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 110 |  | 2times | ⊢ ( ( √ ‘ 𝐷 )  ∈  ℂ  →  ( 2  ·  ( √ ‘ 𝐷 ) )  =  ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) ) ) | 
						
							| 111 | 110 | eqcomd | ⊢ ( ( √ ‘ 𝐷 )  ∈  ℂ  →  ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) )  =  ( 2  ·  ( √ ‘ 𝐷 ) ) ) | 
						
							| 112 | 36 111 | syl | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) )  =  ( 2  ·  ( √ ‘ 𝐷 ) ) ) | 
						
							| 113 | 112 | oveq2d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) ) )  =  ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 114 | 109 113 | eqtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( √ ‘ 𝐷 )  +  ( √ ‘ 𝐷 ) )  +  ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  =  ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 115 | 104 107 114 | 3eqtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) )  =  ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 116 | 115 | fveq2d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) )  =  ( abs ‘ ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) ) | 
						
							| 117 | 47 70 | readdcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) )  ∈  ℝ ) | 
						
							| 118 | 117 | recnd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) )  ∈  ℂ ) | 
						
							| 119 | 118 | abscld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) )  ∈  ℝ ) | 
						
							| 120 | 70 | recnd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 2  ·  ( √ ‘ 𝐷 ) )  ∈  ℂ ) | 
						
							| 121 | 120 | abscld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( 2  ·  ( √ ‘ 𝐷 ) ) )  ∈  ℝ ) | 
						
							| 122 | 57 121 | readdcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  +  ( abs ‘ ( 2  ·  ( √ ‘ 𝐷 ) ) ) )  ∈  ℝ ) | 
						
							| 123 | 48 120 | abstrid | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) )  ≤  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  +  ( abs ‘ ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) ) | 
						
							| 124 |  | 0le2 | ⊢ 0  ≤  2 | 
						
							| 125 | 124 | a1i | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  ≤  2 ) | 
						
							| 126 | 30 32 | sqrtge0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  ≤  ( √ ‘ 𝐷 ) ) | 
						
							| 127 | 69 35 125 126 | mulge0d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  ≤  ( 2  ·  ( √ ‘ 𝐷 ) ) ) | 
						
							| 128 | 70 127 | absidd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( 2  ·  ( √ ‘ 𝐷 ) ) )  =  ( 2  ·  ( √ ‘ 𝐷 ) ) ) | 
						
							| 129 | 128 | oveq2d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  +  ( abs ‘ ( 2  ·  ( √ ‘ 𝐷 ) ) ) )  =  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 130 | 1 | nnsqcld | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐵 ↑ 2 )  ∈  ℕ ) | 
						
							| 131 | 130 | nnge1d | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  1  ≤  ( 𝐵 ↑ 2 ) ) | 
						
							| 132 |  | 0lt1 | ⊢ 0  <  1 | 
						
							| 133 | 132 | a1i | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  0  <  1 ) | 
						
							| 134 |  | lerec | ⊢ ( ( ( 1  ∈  ℝ  ∧  0  <  1 )  ∧  ( ( 𝐵 ↑ 2 )  ∈  ℝ  ∧  0  <  ( 𝐵 ↑ 2 ) ) )  →  ( 1  ≤  ( 𝐵 ↑ 2 )  ↔  ( 1  /  ( 𝐵 ↑ 2 ) )  ≤  ( 1  /  1 ) ) ) | 
						
							| 135 | 67 133 3 87 134 | syl22anc | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 1  ≤  ( 𝐵 ↑ 2 )  ↔  ( 1  /  ( 𝐵 ↑ 2 ) )  ≤  ( 1  /  1 ) ) ) | 
						
							| 136 | 131 135 | mpbid | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 1  /  ( 𝐵 ↑ 2 ) )  ≤  ( 1  /  1 ) ) | 
						
							| 137 |  | 1div1e1 | ⊢ ( 1  /  1 )  =  1 | 
						
							| 138 | 136 137 | breqtrdi | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 1  /  ( 𝐵 ↑ 2 ) )  ≤  1 ) | 
						
							| 139 | 97 138 | eqbrtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( 𝐵 ↑ - 2 )  ≤  1 ) | 
						
							| 140 | 57 64 67 72 139 | ltletrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  1 ) | 
						
							| 141 | 57 67 140 | ltled | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ≤  1 ) | 
						
							| 142 | 57 67 70 141 | leadd1dd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) )  ≤  ( 1  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 143 | 129 142 | eqbrtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  +  ( abs ‘ ( 2  ·  ( √ ‘ 𝐷 ) ) ) )  ≤  ( 1  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 144 | 119 122 71 123 143 | letrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) )  ≤  ( 1  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 145 | 116 144 | eqbrtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) )  ≤  ( 1  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 146 | 103 145 | eqbrtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( ( 𝐵 ↑ - 2 )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  ≤  ( 1  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 147 | 60 66 71 90 146 | ltletrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  ·  ( abs ‘ ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  <  ( 1  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 148 | 56 147 | eqbrtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( ( 𝐵 ↑ 2 )  ·  ( abs ‘ ( ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) )  ·  ( ( 𝐴  /  𝐵 )  +  ( √ ‘ 𝐷 ) ) ) ) )  <  ( 1  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) | 
						
							| 149 | 54 148 | eqbrtrd | ⊢ ( ( ( 𝐷  ∈  ℕ  ∧  𝐴  ∈  ℕ  ∧  𝐵  ∈  ℕ )  ∧  ( abs ‘ ( ( 𝐴  /  𝐵 )  −  ( √ ‘ 𝐷 ) ) )  <  ( 𝐵 ↑ - 2 ) )  →  ( abs ‘ ( ( 𝐴 ↑ 2 )  −  ( 𝐷  ·  ( 𝐵 ↑ 2 ) ) ) )  <  ( 1  +  ( 2  ·  ( √ ‘ 𝐷 ) ) ) ) |