$\frac{\cos 20^{\circ}}{\sin 70^{\circ}}+\frac{\cos \theta}{\sin \left(90^{\circ}-\theta\right)}=$ _________ .
Answer & explanation
Correct answer: option 4
\(\frac{cos20°}{sin70°}\) + \(\frac{cosθ}{sin( 90° -θ ) }\)
We know , sinA = cos( 90° - A )
= \(\frac{cos20°}{cos( 90° - 70° )}\) + \(\frac{cosθ}{cos θ }\)
= \(\frac{cos20°}{cos20° }\) + 1
= 1 + 1
= 2