$\cos \left(\cos ^{-1}\left(-\frac{1}{4}\right)+\sin ^{-1}\left(-\frac{1}{4}\right)\right) = $ . . . . . . .

$\sin^{-1}\left(\frac{2\sqrt{2}}{3}\right) + \sin^{-1}\left(\frac{1}{3}\right)$ નું મૂલ્ય કેટલું થાય?

$\sum\limits_{m = 1}^n {{{\tan }^{ - 1}}} \left( {\frac{{2m}}{{{m^4} + {m^2} + 2}}} \right)$ ની કિંમત શોધો.

જો $\sin ^{-1} x+\cos ^{-1} y=\frac{3 \pi}{10}$ હોય,તો $\cos ^{-1} x+\sin ^{-1} y$ ની કિંમત શોધો.

જો $\theta = \tan^{-1}\left(\frac{1}{3}\right) + \tan^{-1}\left(\frac{1}{7}\right) + \tan^{-1}\left(\frac{1}{13}\right) + \tan^{-1}\left(\frac{1}{21}\right) + \tan^{-1}\left(\frac{1}{31}\right)$,તો $\tan \theta =$

$\tan ^{-1} \frac{1}{3}+\tan ^{-1} \frac{1}{5}+\tan ^{-1} \frac{1}{7}+\tan ^{-1} \frac{1}{8}$ ની કિંમત $ . . . . . . $ છે.