Answer:
Here's your answer:
3pi/4 =x and 5pi/4 =x
cos x + sqrt(2) = - cos x
subtract cos x from each side
cos x - cosx + sqrt(2) = - cos x - cos x
sqrt(2) = -2 cos x
Divide each side by -2
-sqrt(2) / 2 =-2 cos (x) /-2
-sqrt(2) /2 =cos (x)
Take the inverse cos of each side
cos(-1)(-sqrt(2) /2) =cos^-1(cos (x))
3pi/4 =x and 5pi/4 =x
Explanation: