A) \[\frac{3}{4}\]
B) \[1\]
C) \[\frac{1}{2}\]
D) 2
Correct Answer: B
Solution :
\[x=\frac{3-\cos 4\theta +4sin2\theta }{2}\] \[=\frac{3-(1-{{\sin }^{2}}2\theta )+4\sin 2\theta }{2}={{(1+\sin 2\theta )}^{2}}\] \[y=\frac{3-\cos 4\theta -4\sin 2\theta }{2}\] \[=\frac{3-(1-{{\sin }^{2}}2\theta )+4\sin 2\theta }{2}={{(1-\sin 2\theta )}^{2}}\] \[\therefore \,\,xy={{(1-{{\sin }^{2}}2\theta )}^{2}}=\cos {{\,}^{4}}2\theta \le 1\]
You need to login to perform this action.
You will be redirected in
3 sec
