Metamath Proof Explorer


Theorem reeflog

Description: Relationship between the natural logarithm function and the exponential function. (Contributed by Steve Rodriguez, 25-Nov-2007)

Ref Expression
Assertion reeflog ( 𝐴 ∈ ℝ+ → ( exp ‘ ( log ‘ 𝐴 ) ) = 𝐴 )

Proof

Step Hyp Ref Expression
1 rpcnne0 ( 𝐴 ∈ ℝ+ → ( 𝐴 ∈ ℂ ∧ 𝐴 ≠ 0 ) )
2 eflog ( ( 𝐴 ∈ ℂ ∧ 𝐴 ≠ 0 ) → ( exp ‘ ( log ‘ 𝐴 ) ) = 𝐴 )
3 1 2 syl ( 𝐴 ∈ ℝ+ → ( exp ‘ ( log ‘ 𝐴 ) ) = 𝐴 )