Metamath Proof Explorer


Theorem 0dp2dp

Description: Multiply by 10 a decimal expansion which starts with a zero. (Contributed by Thierry Arnoux, 16-Dec-2021)

Ref Expression
Hypotheses 0dp2dp.a ⊢ A ∈ ℕ 0
0dp2dp.b ⊢ B ∈ ℝ +
Assertion 0dp2dp Could not format assertion : No typesetting found for |- ( ( 0 . _ A B ) x. ; 1 0 ) = ( A . B ) with typecode |-

Proof

Step Hyp Ref Expression
1 0dp2dp.a ⊢ A ∈ ℕ 0
2 0dp2dp.b ⊢ B ∈ ℝ +
3 0p1e1 ⊢ 0 + 1 = 1
4 0z ⊢ 0 ∈ ℤ
5 1z ⊢ 1 ∈ ℤ
6 1 2 3 4 5 dpexpp1 Could not format ( ( A . B ) x. ( ; 1 0 ^ 0 ) ) = ( ( 0 . _ A B ) x. ( ; 1 0 ^ 1 ) ) : No typesetting found for |- ( ( A . B ) x. ( ; 1 0 ^ 0 ) ) = ( ( 0 . _ A B ) x. ( ; 1 0 ^ 1 ) ) with typecode |-
7 10nn0 ⊢ 10 ∈ ℕ 0
8 7 nn0cni ⊢ 10 ∈ ℂ
9 exp0 ⊢ 10 ∈ ℂ → 10 0 = 1
10 8 9 ax-mp ⊢ 10 0 = 1
11 10 oveq2i ⊢ A . B ⁢ 10 0 = A . B ⋅ 1
12 exp1 ⊢ 10 ∈ ℂ → 10 1 = 10
13 8 12 ax-mp ⊢ 10 1 = 10
14 13 oveq2i Could not format ( ( 0 . _ A B ) x. ( ; 1 0 ^ 1 ) ) = ( ( 0 . _ A B ) x. ; 1 0 ) : No typesetting found for |- ( ( 0 . _ A B ) x. ( ; 1 0 ^ 1 ) ) = ( ( 0 . _ A B ) x. ; 1 0 ) with typecode |-
15 6 11 14 3eqtr3ri Could not format ( ( 0 . _ A B ) x. ; 1 0 ) = ( ( A . B ) x. 1 ) : No typesetting found for |- ( ( 0 . _ A B ) x. ; 1 0 ) = ( ( A . B ) x. 1 ) with typecode |-
16 1 2 rpdpcl ⊢ A . B ∈ ℝ +
17 rpcn ⊢ A . B ∈ ℝ + → A . B ∈ ℂ
18 16 17 ax-mp ⊢ A . B ∈ ℂ
19 mulrid ⊢ A . B ∈ ℂ → A . B ⋅ 1 = A . B
20 18 19 ax-mp ⊢ A . B ⋅ 1 = A . B
21 15 20 eqtri Could not format ( ( 0 . _ A B ) x. ; 1 0 ) = ( A . B ) : No typesetting found for |- ( ( 0 . _ A B ) x. ; 1 0 ) = ( A . B ) with typecode |-