Metamath Proof Explorer


Definition df-re

Description: Define a function whose value is the real part of a complex number. See reval for its value, recli for its closure, and replim for its use in decomposing a complex number. (Contributed by NM, 9-May-1999)

Ref Expression
Assertion df-re =xx+x2

Detailed syntax breakdown

Step Hyp Ref Expression
0 cre class
1 vx setvarx
2 cc class
3 1 cv setvarx
4 caddc class+
5 ccj class*
6 3 5 cfv classx
7 3 6 4 co classx+x
8 cdiv class÷
9 c2 class2
10 7 9 8 co classx+x2
11 1 2 10 cmpt classxx+x2
12 0 11 wceq wff=xx+x2