Question

please help to solve trignometry class 10 ​

Answer 1

$7\sin^2\theta+3\cos^2\theta=4\\\\7\sin^2\theta+3(1-\sin^2\theta)=4\\\\7\sin^2\theta+3-3\sin^2\theta=4\\\\4\sin^2\theta+3=4\\\\4\sin^2\theta=1\\\\\sin^2\theta=\dfrac {1}{4}$

$\cos^2\theta=1-\sin^2\theta=\dfrac {3}{4}\\\\\sec^2\theta=\dfrac {4}{3}\\\\\tan^2\theta=\sec^2\theta-1=\dfrac {1}{3}\\\\\tan\theta=\pm\dfrac {1}{\sqrt{3}}$