About Inverse of a Function:

Every one-to-one function has an inverse. To find the inverse of a function, we start by writing f(x) as y. Then we swap the x and y variables. Now, we solve for y. Lastly, we replace y with a special notation: f-1(x), which is read as f inverse of x.


Test Objectives
  • Demonstrate the ability to find the inverse of a function
Inverse of a Function Practice Test:

#1:

Instructions: find the inverse of each function.

$$a)\hspace{.2em}f(x)=2x + 1$$

$$b)\hspace{.2em}f(x)=\sqrt[3]{x}- 2$$


#2:

Instructions: find the inverse of each function.

$$a)\hspace{.2em}f(x)=\frac{3}{7}x - \frac{6}{7}$$

$$b)\hspace{.2em}f(x)=\frac{1}{x - 2}+ 2$$


#3:

Instructions: find the inverse of each function.

$$a)\hspace{.2em}f(x)=-2 + (x - 1)^3$$

$$b)\hspace{.2em}f(x)=-x^3 - 1$$


#4:

Instructions: find the inverse of each function.

$$a)\hspace{.2em}f(x)=\sqrt[5]{x}+ 2$$

$$b)\hspace{.2em}f(x)=\frac{2}{x - 2}$$


#5:

Instructions: find the inverse of each function.

$$a)\hspace{.2em}f(x)=\frac{x - 2}{3x - 1}$$

$$b)\hspace{.2em}f(x)=\frac{x - 1}{2x - 4}$$


Written Solutions:

#1:

Solutions:

$$a)\hspace{.2em}f^{-1}(x)=\frac{x - 1}{2}$$

$$b)\hspace{.2em}f^{-1}(x)=(x + 2)^3$$


#2:

Solutions:

$$a)\hspace{.2em}f^{-1}(x)=\frac{7x + 6}{3}$$

$$b)\hspace{.2em}f^{-1}(x)=\frac{2x - 3}{x - 2}$$


#3:

Solutions:

$$a)\hspace{.2em}f^{-1}(x)=\sqrt[3]{x + 2}+ 1$$

$$b)\hspace{.2em}f^{-1}(x)=\sqrt[3]{-x - 1}$$


#4:

Solutions:

$$a)\hspace{.2em}f^{-1}(x)=(x - 2)^5$$

$$b)\hspace{.2em}f^{-1}(x)=\frac{2x + 2}{x}$$


#5:

Solutions:

$$a)\hspace{.2em}f^{-1}(x)=-\frac{x - 2}{1 - 3x}$$

$$b)\hspace{.2em}f^{-1}(x)=-\frac{4x - 1}{1 - 2x}$$