MCQ
If $\sin \theta + {\rm{cosec}}\theta = {\rm{2}}$, then ${\sin ^2}\theta + {\rm{cose}}{{\rm{c}}^{\rm{2}}}\theta = $
- A$1$
- B$4$
- ✓$2$
- DNone of these
$= {(\sin \theta + {\rm{cosec}}\theta )^2} - 2\sin \theta {\rm{ cosec}}\theta $
$ = {(2)^2} - 2 = 4 - 2 = 2,$
since $(\sin \theta + {\rm{cosec}}\theta ) = 2.$
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