Question

Question #1629c

Answer 1

`sin(arctan(x/2) )`

`=>sin(arc cot(2/x)`

`=>sin(arc cscsqrt(1+(2/x)^2))`

`=>sin(arc csc(sqrt(x^2+4)/x))`

`=>sin(arcsin(x/sqrt(x^2+4)))`

`=>x/sqrt(x^2+4)`