Solve the following equation: `sin^2theta-costheta=1/4`

Solve the following equation: sin^(2)theta-cos theta=(1)/(4)

Solve the following equation: sin2 theta+cos theta=0

Solve that following equations: sin theta+cos theta=1

Solve the following equation: sin3 theta+cos2 theta=0

Solve the following equation: k 4sin^(2)theta-8cos theta+1=0

Solve the following equation: cos4 theta=cos2 theta

Solve the following equation: cos^(2)theta-sin theta cos theta-(1)/(2)=0

Solve the following equation: s in2 theta+sin4 theta+s in6 theta=0

Solve that following equations : 2sin^(2)theta=3cos theta,0<=theta<=(pi)/(2)

Solve the following equations : i) tantheta=cottheta , ii) cos2theta=2sin^(2)theta iii) tan3theta=-sqrt(3) , iv) sin2theta-costheta=0 v) sec^(2)2theta=1-tan2theta