Solve `7cos^2theta+3sin^2theta=4` – InterviewSolution

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1.	Solve `7cos^2theta+3sin^2theta=4`
Answer» `7cos^2theta+3sin^2theta=4` `4cos^2theta+3cos^2theta+2sin^2theta=4` `4cos^2theta+3=4` `4cos^2theta=1` `cos^2theta=1/4` `costheta=pm1/2` `theta=npipmpi/3`.

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