# How do you use the quotient rule to differentiate #1 / (1 + x²)#?

##### 1 Answer

Feb 26, 2017

The quotient rule states that the derivative of some function that's expressed as a quotient of two other functions, such as if

#f'(x)=(g'(x)h(x)-g(x)h'(x))/(h(x))^2#

For

We then see that

#f'(x)=(0(1+x^2)-1(2x))/(1+x^2)^2#

#f'(x)=(-2x)/(1+x^2)^2#

**Footnote**

If you've learned the chain rule, it's easier to do this by rewriting the function as