Answer:
x = 0°, 360°
Step-by-step explanation:
- Formula : cos²x + sin²x = 1
- so sin²x = 1 - cos²x
using the formula:
cosx - 1 = 1 - cos²x
cos²x +cosx - 1 - 1 = 0
cos²x +cosx - 2 = 0
cos²x + 2cosx - cosx -2 = 0
cosx ( cosx + 2 ) -1 ( cosx + 2 ) = 0
(cosx - 1) (cosx + 2 ) = 0
cosx = 1 , cosx = -2
[tex]x = cos^{-1} ( 1 )[/tex] , [tex]x = cos^{-1} ( -2 )[/tex]
x = 0° , 360° , Not applicable
