Find the real Solution of
${\tan ^{ – 1}}\sqrt {x(x + 1)} + {\sin ^{ – 1}}\sqrt {{x^2} + x + 1} = \frac{\pi }{2}$.
[NCERT,Exemplar.2.3,Q.7,Page.36]
Show that $2{\tan ^{ – 1}}( – 3) = \frac{{ – \pi }}{2} + {\tan ^{ – 1}}\left( {\frac{{ – 4}}{3}} \right)$.
[NCERT,Exemplar.2.3,Q.6,Page.35]