Axiom ax-i2m1 8290

Description: i-squared equals -1 (expressed as i-squared plus 1 is 0). Axiom for real and complex numbers, justified by Theorem axi2m1 8248. (Contributed by NM, 29-Jan-1995.)

Assertion

Ref	Expression
ax-i2m1	|- ( ( _i x. _i ) + 1 ) = 0

Detailed syntax breakdown of Axiom ax-i2m1

Step	Hyp	Ref	Expression
1		ci 8187	. . . 4 class _i
2		cmul 8190	. . . 4 class x.
3	1, 1, 2	co 6088	. . 3 class ( _i x. _i )
4		c1 8186	. . 3 class 1
5		caddc 8188	. . 3 class +
6	3, 4, 5	co 6088	. 2 class ( ( _i x. _i ) + 1 )
7		cc0 8185	. 2 class 0
8	6, 7	wceq 1402	1 wff ( ( _i x. _i ) + 1 ) = 0

This axiom is used by:  0cn  8324  ine0  8728  ixi  8919  inelr  8920