Evaluate: sin 21°/ cos 69°

Question

Evaluate:

\(\frac{sin\, 21°}{cos\, 69°}\)

Answer 1

We have, 

\(\frac{sin 21^o}{cos 69^o }\)

= \(\frac{sin (90^o – 69^o)}{cos 69^o }\)

= \(\frac{cos 69^o}{ cos69^o }\)

= 1 [∵ sin (90 – θ) = cos θ]