1+sin^2x+cosx=0 Хелп плз(

Question

1+sin^2x+cosx=0
Хелп плз(

Answer 1

1+sin^2x+cosx = 0 
1+1-cos^2x+cosx = 0
cos^2x-cosx-2 = 0
cosx = t, cos^2x = t^2, -1≤t≤1
t^2-t-2 = 0
D = 1+4*2 = 9
t1 = -1
t2 = 2 - не подходит.
cos x = -1
x = П+2Пn, n∈Z