Question #c21c1

1 Answer
Jan 12, 2018

x=0°,180°,360°

Explanation:

#Cos^2x=sin^2x + 1#

(#sin^2x=1 - cos^2#)

#cos^2x=1 - cos^2 + 1#

#cos^2x + cos^2x = 1+1#

#2cos^2x = 2#

#cos^2x = 1#

#cosx = +-1#

This is possible when x=0°,180°,360°

Hope it helps you