Railways PYQCBT 1 2020

RRB NTPC · Question 85

If \(\sin \theta =\frac{3}{5}\) and \(\cos \theta =\frac{4}{5}\), then the value of \(\frac{1+\tan \theta}{1-\cot \theta}\) is:

  1. \(\frac{11}{5}\)

  2. \(\frac{2}{5}\)

  3. \(\frac{-21}{4}\)

  4. \(\frac{-8}{5}\)

Show answer & explanation

Answer: (C) \(\frac{-21}{4}\)

Explanation

tan θ = 3/4 and cot θ = 4/3. (1 + 3/4)/(1 − 4/3) = (7/4)/(−1/3) = −21/4.