How would I solve
$$a\cos^2(\theta) + b \sin^2(\theta) = 0$$
for $\theta$. Here $a,b$ are constants and $a \neq b, a \neq 0, b \neq0$.
I thought there might not be any solutions but with the constants $a,b,$ in front of them, I thought it is possible that they could be negative and the "right" constants to make the whole thing equal $0$.
So how would I solve this?