Question:
The equation $y=\sin x \sin (x+2)-\sin ^{2}(x+1)$ represents a straight line lying in :
Correct Option: , 2
Solution:
$2 y=2 \sin x \sin (x+2)-2 \sin ^{2}(x+1)$
$2 y=\cos 2-\cos (2 x+2)-(1-\cos (2 x+2))$
$=\cos 2-1$
$2 y=-2 \sin ^{2} \frac{1}{2}$
$y=-\sin ^{2} \frac{1}{2} \leq 0$