Question

PROVE :sin^2(-300°).cos^2 (120)+ cos^2(-240 ).sin^2(390)=1/4​

Answer 1

Step-by-step explanation:

$\sin {}^{2} ( - 300) \cos {}^{2} (120) + \cos {}^{2} ( - 240) \sin {}^{2} (390) = \frac{1}{4}$

$\sin {}^{2} (60) \cos {}^{2} ( {}^{} 120) + \cos {}^{2} (120) \sin {}^{2} (30)$

$\frac{3}{4} \frac{1}{4} + \frac{1}{4} \frac{1}{4}$

$\frac{3}{16} + \frac{1}{16} = \frac{4}{16} = \frac{1}{4}$