Question

find the integral of {1}/ (sqrt){1-x^2}

Answer 1

well, just memorized that integral of 1/sqrt(1-x^2) is arcsin(x)

Answer 2

To derive the formula for yourself, use a trig sub:
x = sin(u)
dx = cos(u) du

So you have
Int[ cos(u)/√( 1 - sin²(u) ) du ]
= Int[ cos(u)/√( cos²(u) ) du ]
= Int[ cos(u) / cos(u) du ]
= Int[ du ]
= ∙∙∙

Answer 3

i will try that @SithsAndGiggles

Answer 4

or just memorize it like every other one. i.e arcsec/arctan