SOLUTION: Solve the equation on the interval 0<x<360 Cos^2 (x) + 2cos(x) + 1= 0

Algebra ->  Trigonometry-basics -> SOLUTION: Solve the equation on the interval 0<x<360 Cos^2 (x) + 2cos(x) + 1= 0       Log On


   

Question 865563: Solve the equation on the interval 0
Cos^2 (x) + 2cos(x) + 1= 0
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

Cos^2 (x) + 2cos(x) + 1= 0 

let X  = cos(x)

X^2 + 2X + 1 = 0, X = -1

COS(x) = -1 , x = 180° or any angle 180°  (0 ≤ x ≤ 2pi)