Metamath Proof Explorer


Theorem min2

Description: The minimum of two numbers is less than or equal to the second. (Contributed by NM, 3-Aug-2007)

Ref Expression
Assertion min2 ( ( 𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ) → if ( 𝐴 ≤ 𝐵 , 𝐴 , 𝐵 ) ≤ 𝐵 )

Proof

Step Hyp Ref Expression
1 rexr ⊢ ( 𝐴 ∈ ℝ → 𝐴 ∈ ℝ* )
2 rexr ⊢ ( 𝐵 ∈ ℝ → 𝐵 ∈ ℝ* )
3 xrmin2 ⊢ ( ( 𝐴 ∈ ℝ* ∧ 𝐵 ∈ ℝ* ) → if ( 𝐴 ≤ 𝐵 , 𝐴 , 𝐵 ) ≤ 𝐵 )
4 1 2 3 syl2an ⊢ ( ( 𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ) → if ( 𝐴 ≤ 𝐵 , 𝐴 , 𝐵 ) ≤ 𝐵 )