Metamath Proof Explorer


Theorem dp20u

Description: Add a zero in the tenths (lower) place. (Contributed by Thierry Arnoux, 16-Dec-2021)

Ref Expression
Hypothesis dp20u.1 ⊢ A ∈ ℕ 0
Assertion dp20u Could not format assertion : No typesetting found for |- _ A 0 = A with typecode |-

Proof

Step Hyp Ref Expression
1 dp20u.1 ⊢ A ∈ ℕ 0
2 df-dp2 Could not format _ A 0 = ( A + ( 0 / ; 1 0 ) ) : No typesetting found for |- _ A 0 = ( A + ( 0 / ; 1 0 ) ) with typecode |-
3 10nn0 ⊢ 10 ∈ ℕ 0
4 3 nn0rei ⊢ 10 ∈ ℝ
5 4 recni ⊢ 10 ∈ ℂ
6 0re ⊢ 0 ∈ ℝ
7 10pos ⊢ 0 < 10
8 6 7 gtneii ⊢ 10 ≠ 0
9 div0 ⊢ 10 ∈ ℂ ∧ 10 ≠ 0 → 0 10 = 0
10 5 8 9 mp2an ⊢ 0 10 = 0
11 10 oveq2i ⊢ A + 0 10 = A + 0
12 1 nn0cni ⊢ A ∈ ℂ
13 12 addridi ⊢ A + 0 = A
14 2 11 13 3eqtri Could not format _ A 0 = A : No typesetting found for |- _ A 0 = A with typecode |-