Question

`cosx -1 =sin^(2)x` solution

Answer 1

x = 0°, 360°

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

`x = cos^(-1) ( 1 )` ,
`x = cos^(-1) ( -2 )`

x = 0° , 360° , Not applicable