Metamath Proof Explorer


Theorem xdivid

Description: A number divided by itself is one. (Contributed by Thierry Arnoux, 18-Dec-2016)

Ref Expression
Assertion xdivid ⊢ A ∈ ℝ ∧ A ≠ 0 → A ÷ 𝑒 A = 1

Proof

Step Hyp Ref Expression
1 rexdiv ⊢ A ∈ ℝ ∧ A ∈ ℝ ∧ A ≠ 0 → A ÷ 𝑒 A = A A
2 1 3anidm12 ⊢ A ∈ ℝ ∧ A ≠ 0 → A ÷ 𝑒 A = A A
3 recn ⊢ A ∈ ℝ → A ∈ ℂ
4 divid ⊢ A ∈ ℂ ∧ A ≠ 0 → A A = 1
5 3 4 sylan ⊢ A ∈ ℝ ∧ A ≠ 0 → A A = 1
6 2 5 eqtrd ⊢ A ∈ ℝ ∧ A ≠ 0 → A ÷ 𝑒 A = 1