Find the derivative if y=sin^-1 (3x)

Answer 1

Use the fact that , for f(u) = arcsin u,
df/du = 1 / sqrt(1 - u^2)
Use the chain rule: df/dx = df/du* du/dx
Let u = 3x, so du/dx = 3
df/dx = 3 / sqrt(1 - 9x^2)