Question

Question #37b65

Answer 1

First expression

`=sintan^-1(x/3)`

`=sincot^-1(3/x)`

`=sincsc^-1sqrt(1+(3/x)^2)`

`=sincsc^-1sqrt((x^2+9)/x^2)`

`=sinsin^-1sqrt(x^2/(x^2+9))`

`=x/sqrt((x^2+9))`

2nd expression

`=sin(2tan^-1(x/3))`

`=(2tantan^-1(x/3))/(1+(tantan^-1(x/3))^2)`

`=((2x)/3)/(1+x^2/9)=(6x)/(9+x^2)`