Let Then which one of the following is true

If cos^-1(3/5) - sin^-1(4/5) = cos^-1(x), then x

If Cos^-1 x= Tan^-1 x, then sin(Cos^-1 x)=

If Tan^-1 (sec x + tan x)=π/4+kx then k=

The domain of Cos^-1 (2/2+sinx) in [0,2π] is

Sin^-1(3/5)+Sin^-1(8/17)=

If Tan^-1(x+1/x-1)+Tan^-1(x-1/x)+ Tan^-1(1/3), then x=

Tan (tan^-1 1/2+ tan^-11/3) =

The range of f(x)= Sin^-1x-cos^-1x + Tan^-1x is

If Tan^-1(x-1/x-2)+ Cot^-1 (x+2/x+1)=π/4, then x=