Theorem it1ei

Description: _i times 1 equals _i . (Contributed by SN, 25-Apr-2025)

	Ref	Expression
Assertion	it1ei	|- ( _i x. 1 ) = _i

Proof

Step	Hyp	Ref	Expression
1		ax-icn	|- _i e. CC
2	1	mulridi	|- ( _i x. 1 ) = _i