Theorem sq2

Description: The square of 2 is 4. (Contributed by NM, 22-Aug-1999)

	Ref	Expression
Assertion	sq2	|- ( 2 ^ 2 ) = 4

Proof

Step	Hyp	Ref	Expression
1		2cn	|- 2 e. CC
2	1	sqvali	|- ( 2 ^ 2 ) = ( 2 x. 2 )
3		2t2e4	|- ( 2 x. 2 ) = 4
4	2 3	eqtri	|- ( 2 ^ 2 ) = 4