# find the domain of root of cosx(sinx)+sin^-1{1+x^2/2x}please give the solution

Arun Kumar IIT Delhi
8 years ago
Hi
$\\see \\1+x^2 \geq 2\sqrt{1*x^2} \\=>1+x^2 \geq 2|x| \\=>{1+x^2 \over 2x} \geq {|x| \over x} \\=>{1+x^2 \over 2x} \in (-\infty,-1] \bigcup [1,\infty)$
Checking in -1 and +1 we found only 1 gives positive value to the argument of the root

Arun Kumar, Btech, IIT delhi, Askiitians Faculty