Database
REAL AND COMPLEX NUMBERS
Elementary real and complex functions
Real and imaginary parts; conjugate
re1
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im1
Metamath Proof Explorer
Ascii
Structured
Theorem
re1
Description:
The real part of one.
(Contributed by
Scott Fenton
, 9-Jun-2006)
Ref
Expression
Assertion
re1
⊢
( ℜ ‘ 1 ) = 1
Proof
Step
Hyp
Ref
Expression
1
1re
⊢
1 ∈ ℝ
2
rere
⊢
( 1 ∈ ℝ → ( ℜ ‘ 1 ) = 1 )
3
1
2
ax-mp
⊢
( ℜ ‘ 1 ) = 1