MCQ
A value of ${\tan ^{ - 1}}\,\,\left( {\sin \,\left( {{{\cos }^{ - 1}}\left( {\sqrt {\frac{2}{3}} } \right)} \right)} \right)$ is
- A$\frac {\pi }{4}$
- B$\frac {\pi }{2}$
- C$\frac {\pi }{3}$
- ✓$\frac {\pi }{6}$
Let ${\cos ^{ - 1}}\sqrt {\frac{2}{3}} = \theta \Rightarrow \cos \theta = \sqrt {\frac{2}{3}} $
$ \Rightarrow \sin \theta = \sqrt {1 - {{\cos }^2}\theta } = \sqrt {1 - \frac{2}{3}} = \sqrt {\frac{1}{3}} $
$\therefore {\tan ^{ - 1}}\left[ {\sin \left( {{{\cos }^{ - 1}}\sqrt {\frac{2}{3}} } \right)} \right] = {\tan ^{ - 1}}\left[ {\sin \theta } \right]$
$ = {\tan ^{ - 1}}\left[ {\sqrt {\frac{1}{3}} } \right] = {\tan ^{ - 1}}\left( {\frac{1}{{\sqrt 3 }}} \right)$
$ = \frac{\pi }{6}$
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0
1
3
$\frac{2}{\sqrt{26}}$
If
$\text{P}(\text{A})=\frac{2}{5},\text{P}(\text{B})=\frac{3}{5}$ and $\text{P}(\text{A}\cap\text{B})=\frac{1}{5},$ then $\text{P}\Big(\frac{\text{A}'}{\text{B}'}\Big)\cdot\text{P}\Big(\frac{\text{B}'}{\text{A}'}\Big)$ is equas:$\frac{5}{6}$
$\frac{5}{7}$
$\frac{25}{42}$
$1$