Solve for z. z^4 + 1 = 0

Answer 1

|| z || = 1

θ = 180°

z^1/4 =

1(cos 180° / 4 + i sin 180° / 4)

1(cos 540° / 4 + i sin 540 / 4 )

1(cos 900° / 4 + i sin 900 / 4)

1(cos 1260° / 4 + i sin 1)260 / 4

Answer 2

z^4 + 1 = 0

z^4=-1

=i

"i" is the ^.5 of -1.