Simplify both sides by cos^2 tcos2t. (Condition cos x different to 0)
The remainder equation is:
1/(cos^2 t) + 5 = 3(sin^2 t)/(cos^2 t)1cos2t+5=3sin2tcos2t
(1 + 5cos^2 t)/(cos^2 t) = (3sin^2 t)/(cos^2 t)1+5cos2tcos2t=3sin2tcos2t
Simplify both sides by cos^2 t. cos2t.
Replace in the equation 3sin^2 t3sin2t by (3 - 3cos^2 t) (3−3cos2t)-->
1 + 5cos^2 t = 3 - 3cos^2 t1+5cos2t=3−3cos2t
8cos^2 t = 28cos2t=2 --> cos^2 t = 2/8 = 1/4cos2t=28=14
cos t = +- 1/2cost=±12
Trig table and unit circle -->
cos t = +- 1/2cost=±12 --> t = +- pi/3t=±π3
General answer:
t = +- pi/3 + 2kpit=±π3+2kπ