Metamath Proof Explorer


Theorem xaddlid

Description: Extended real version of addlid . (Contributed by Mario Carneiro, 20-Aug-2015)

Ref Expression
Assertion xaddlid ⊢ A ∈ ℝ * → 0 + 𝑒 A = A

Proof

Step Hyp Ref Expression
1 0xr ⊢ 0 ∈ ℝ *
2 xaddcom ⊢ 0 ∈ ℝ * ∧ A ∈ ℝ * → 0 + 𝑒 A = A + 𝑒 0
3 1 2 mpan ⊢ A ∈ ℝ * → 0 + 𝑒 A = A + 𝑒 0
4 xaddrid ⊢ A ∈ ℝ * → A + 𝑒 0 = A
5 3 4 eqtrd ⊢ A ∈ ℝ * → 0 + 𝑒 A = A