What is the derivative of this function y=1/arcsin(2x)y=1arcsin(2x)?

1 Answer
Nov 8, 2016

Start by differentiating y = arcsin(2x)y=arcsin(2x).

y = arcsin(2x) -> siny = 2xy=arcsin(2x)siny=2x

Through implicit differentiation, we have:

cosy(dy/dx) = 2cosy(dydx)=2

dy/dx = 2/(cosy)dydx=2cosy

Apply the identity cosy = sqrt(1 - sin^2(y))cosy=1sin2(y)

dy/dx = 2/sqrt(1 - sin^2y) = 2/sqrt(1 - 4x^2) ->" since siny = 2x"dydx=21sin2y=214x2 since siny = 2x

So, now we can differentiate the entire expression using the quotient rule.

dy/dx = (0 xx arcsin(2x) - 2/sqrt(1 - 4x^2))/(arcsin(2x))^2dydx=0×arcsin(2x)214x2(arcsin(2x))2

dy/dx = -2/((sqrt(1 - 4x^2))(arcsin(2x))^2)dydx=2(14x2)(arcsin(2x))2

Hopefully this helps!