Consider the following statements

1. $${\tan ^{ - 1}}x + {\tan ^{ - 1}}\left( {{1 \over x}} \right) = \pi $$

2. Their exist, $$x,y \in [ - 1,1]$$, where x $$\ne$$ y such that $${\sin ^{ - 1}}x + {\cos ^{ - 1}}y = {\pi \over 2}$$.

Which of the above statements is/are correct?

The value of $${\sin ^{ - 1}}\left( {{3 \over 5}} \right) + {\tan ^{ - 1}}\left( {{1 \over 7}} \right)$$ is equal to

The principal value of $${\sin ^{ - 1}}x$$ lies in the interval

Let x, y, z be positive real numbers such that x, y, z are in GP and $${\tan ^{ - 1}}x$$, $${\tan ^{ - 1}}y$$ and $${\tan ^{ - 1}}z$$ are in AP. Then which one of the following is correct?