Metamath Proof Explorer


Theorem xleadd2a

Description: Commuted form of xleadd1a . (Contributed by Mario Carneiro, 20-Aug-2015)

Ref Expression
Assertion xleadd2a ⊢ A ∈ ℝ * ∧ B ∈ ℝ * ∧ C ∈ ℝ * ∧ A ≤ B → C + 𝑒 A ≤ C + 𝑒 B

Proof

Step Hyp Ref Expression
1 xleadd1a ⊢ A ∈ ℝ * ∧ B ∈ ℝ * ∧ C ∈ ℝ * ∧ A ≤ B → A + 𝑒 C ≤ B + 𝑒 C
2 xaddcom ⊢ A ∈ ℝ * ∧ C ∈ ℝ * → A + 𝑒 C = C + 𝑒 A
3 2 3adant2 ⊢ A ∈ ℝ * ∧ B ∈ ℝ * ∧ C ∈ ℝ * → A + 𝑒 C = C + 𝑒 A
4 3 adantr ⊢ A ∈ ℝ * ∧ B ∈ ℝ * ∧ C ∈ ℝ * ∧ A ≤ B → A + 𝑒 C = C + 𝑒 A
5 xaddcom ⊢ B ∈ ℝ * ∧ C ∈ ℝ * → B + 𝑒 C = C + 𝑒 B
6 5 3adant1 ⊢ A ∈ ℝ * ∧ B ∈ ℝ * ∧ C ∈ ℝ * → B + 𝑒 C = C + 𝑒 B
7 6 adantr ⊢ A ∈ ℝ * ∧ B ∈ ℝ * ∧ C ∈ ℝ * ∧ A ≤ B → B + 𝑒 C = C + 𝑒 B
8 1 4 7 3brtr3d ⊢ A ∈ ℝ * ∧ B ∈ ℝ * ∧ C ∈ ℝ * ∧ A ≤ B → C + 𝑒 A ≤ C + 𝑒 B