Question

is x=15 degrees a solution of (( sqrt3)/3) cos2x+sin2x=1? how can i figure this out?

Answer 1

just substitute x = 15 into each trig ratio and use the exact angle identities below



if x =15 then 2x = 30....

use the exact values from the triangle above for cos2(15) = cos(30) ans sin2(15) = sin(30)