Suppose the function f(x) = xⁿ, n $$\ne$$ 0 is differentiable for all x. Then n can be any element of the interval

If $$y = {\tan ^{ - 1}}\left( {{{5 - 2\tan \sqrt x } \over {2 + 5\tan \sqrt x }}} \right)$$, then what is $${{dy} \over {dx}}$$ equal to ?

If $$u = {e^{ax}}\sin bx$$ and $$v = {e^{ax}}\cos bx$$, then what is $$u{{du} \over {dx}} + v{{dv} \over {dx}}$$ equal to ?

If $$y = \sin (\ln x)$$, then which one of the following is correct?