# What is the derivative of #arctan(x/3)#?

##### 2 Answers

#### Explanation:

#"differentiate using the "color(blue)"chain rule"#

#•color(white)(x)d/dx(arctan(f(x)))=1/(1+(f(x))^2)xxf'(x)#

#rArrd/dx(arctan(x/3))#

#=1/(1+x^2/9)xxd/dx(1/3x)#

#=1/(3(1+x^2/9))=1/(3+x^2/3)#

If you haven't memorized the drivative of

#### Explanation:

Diiferentiate implicitly.

Use

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