If $7\cos^2 heta + 3\sin^2 heta = 4$, then the value of $ heta$ is:

Question

If $7\cos^2	heta + 3\sin^2	heta = 4$, then the value of $	heta$ is:

Accepted Answer

Step 1: $7\cos^2	heta + 3\sin^2	heta = 4$
$7\cos^2	heta + 3(1 - \cos^2	heta) = 4$
$4\cos^2	heta = 1$
$\cos^2	heta = \frac{1}{4}$
$\cos	heta = \frac{1}{2}$
$	heta = 60°$

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