( + ) ( - ) , cose c ^2 = - Vidyadip

MCQ

$\sin (\pi + \theta )\sin (\pi - \theta )\,{\rm{ cose}}{{\rm{c}}^2}\theta = $

A
$1$
✓
$-1$
C
$\sin \theta $
D
$ - \sin \theta $

✓

Answer

Correct option: B.

$-1$

b
(b) $\sin (\pi + \theta )\sin (\pi - \theta ){\rm{cose}}{{\rm{c}}^2}\theta $

$ = - \sin \theta \sin \theta \frac{1}{{{{\sin }^2}\theta }} = - 1$.

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