Let be an acute angle such that

MATHEMATICS · Subjective · CBSE · Mathematics · Introduction to Trigonometry · Introduction to Trigonometry

Problem

Let

\alpha

be an acute angle such that

\cot \alpha=\dfrac{4}{5}

. Calculate the following: (i)

\csc \alpha

(ii)

\sec \alpha

(iii) the value of

\displaystyle \frac{1+\tan^{2}\alpha}{\csc^{2}\alpha}