# Thread: How to Turn this Trig f(x) into a Non-Trig f(x)

1. ## How to Turn this Trig f(x) into a Non-Trig f(x)

Ok how can I turn this trig function into a function that doesn't use any trig functions?

$f(x)=sin(\arctan(x))$

2. Draw a right triangle with sides 1, x and $\sqrt(1+x^2)$.

Can you find the angle whose tangent is x (hint - opposite over adjacent = x/1)?

That's arctan(x). Now look at the triangle. What is the sine of that angle? (hint = opposite / hypotenuse). That's what you're looking for.