Inverse Trigono...

Sum of maximum and minimum values of (sin$$^{-1}$$x)$$^4$$ + (cos$$^{-1}$$x)$$^4$$ is:

$$\displaystyle \sum^{\infty}_{r=1}\tan^{-1}\left(\dfrac {1}{r^{2}+5r+7}\right)$$ equal to

if $${ tan }^{ -1 }\frac { \sqrt { 1+{ x }^{ 2 }-1 }  }{ x } =4\quad then\quad x$$

Number of values of x for which $$(tan^{-1} x)^2 + (cot^{-1} x)^2 = \dfrac{\pi^2}{4}$$ is 

The value of $$3 tan^-1\left(\dfrac{1}{2}\right)+ 2tan^-1 \left(\dfrac{1}{5}\right)$$ is-

The value of sin $$\left ( 3 sin^{-1}\left ( 0.8 \right ) \right )$$ is

If $$f(x)=2tan^{-1}x+sin^{-1}\left (\dfrac {2x}{1+x^2}\right )$$ then for x>1, f(x)=

If $$(\cos^{-1}x)^{2}+(\cos^{-1}y)^{2}+2(\cos^{-1}x)(\cos^{-1}y)=4\pi^{2}$$ then $$x^{2}+y^{2}$$ is equal to 

If $${ \tan \text{h} }^{ -1 }\left( \dfrac { 1 }{ 3 }  \right) =\dfrac { 1 }{ 2 } \log t ,$$ then $$t$$ is equal to

If $$f\left( x \right) =\cos ^{ -1 }{ x } +\cos ^{ -1 }{ \left\{ \frac { x }{ 2 } +\dfrac { 1 }{ 2 } \sqrt {  3-3{ x }^{ 2 } }  \right\}  } $$ then