Question

How do you find the derivative of `f(x)=sqrt(169-x^2)`?

Answer 1

Using chain rule, which states that `dy/dx=(dy)/(du)(du)/dx`.

Explanation:

Here, we'll rename `y=sqrt(u)` and `u=169-x^2`

Thus:

`(dy)/(dx)=1/(2(u)^(1/2))*(-2x)=-1/sqrt((169-x^2))`