Theorem sq1

Description: The square of 1 is 1. (Contributed by NM, 22-Aug-1999)

	Ref	Expression
Assertion	sq1	⊢ ( 1 ↑ 2 ) = 1

Proof

Step	Hyp	Ref	Expression
1		2z	⊢ 2 ∈ ℤ
2		1exp	⊢ ( 2 ∈ ℤ → ( 1 ↑ 2 ) = 1 )
3	1 2	ax-mp	⊢ ( 1 ↑ 2 ) = 1