How do you find all solutions of #2cos^2 3theta = cos 3theta#?
1 Answer
Feb 6, 2015
The answers are:

#costheta=0rArrtheta=pi/2+kpi# , this means that#theta# can be#pi/2and3/2pi# . 
#2cos^2theta=1rArrcos^2theta=1/2rArrcostheta=+sqrt(1/2)=+1/sqrt2=+sqrt2/2rArr# #theta=pi/4+kpi/2# ,this means that#theta# can be#pi/4,3/4pi5/4pi,7/4pi# .