MCQ
Which of the following is the correct identity?
  • A
    $\cot \left(\frac{\pi}{2}+A\right)=\tan A$
  • $\sec \left(\frac{7 \pi}{2}-A\right)=-\operatorname{cosec} A$
  • C
    $\sin (n \pi+A)=(-1)^{2 n} \sin A$
  • D
    $\sin (\pi-A)=-\sin A$

Answer

Correct option: B.
$\sec \left(\frac{7 \pi}{2}-A\right)=-\operatorname{cosec} A$
(B)
$\sec \left(\frac{7 \pi}{2}-A\right)=\sec \left(2 \pi+\frac{3 \pi}{2}-A\right)$
$=\sec \left(\frac{3 \pi}{2}- A \right)=-\operatorname{cosec} A$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free