SSC CHSL 2023 PYQ — Question 56

SSC CHSL - 10 Aug 2023 - Shift 4 • Quantitative Aptitude • Q56

Find the value of the following expression.

(1+secØ)secØ(1−cosØ)\frac{(1 + secØ)}{ secØ} (1-cosØ)


 

Show answer & explanation

Correct answer: D

Explanation

The correct answer is option 4 i.e. sin2Ø.

(1+sec⁡Ø)sec⁡Ø(1−cos⁡Ø)\frac{(1 + \sec Ø)}{\secØ} (1 - \cosØ)

=(1+1cos⁡Ø)1cos⁡Ø(1−cos⁡Ø)=\frac{(1 + \frac{1}{\cos Ø})}{\frac{1}{\cos Ø}} (1 - \cosØ)

=cosØ+1cosØ1cosØ(1−cos⁡Ø)=\frac{\frac{cosØ+1}{cosØ}}{\frac{1}{cosØ}}(1 - \cos Ø)

=(cos⁡Ø+1)(1−cos⁡Ø)=(\cos Ø + 1) (1 - \cosØ)

= 1 - cos2Ø

= sin2Ø

Hence, the value of the expression is sin2Ø.