Which of the following expressions is identically equal to for every acute angle ?

MATHEMATICS · Single correct · CBSE · Mathematics · Introduction to Trigonometry · Introduction to Trigonometry

Problem

Which of the following expressions is identically equal to

1

for every acute angle

\theta

? (a)

\dfrac{\sin(90^\circ-\theta)}{\sin\theta}

(b)

\sin(90^\circ-\theta)\,\cos\theta

(c)

\dfrac{\sin(90^\circ-\theta)}{\cos\theta}

(d)

\dfrac{\sin(90^\circ-\theta)}{\cot\theta}