How to determine if two functions are inverses calculator

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So, how do we check to see if two functions are inverses of each other?

Well, we learned before that we can look at the graphs.  Remember, if the two graphs are symmetric with respect to the line y = x (mirror images over y = x ), then they are inverse functions.

But, we need a way to check without the graphs, because we won't always know what the graphs look like!

So, just crunching some Algebra, here's one way to look at it:

If you're got two functions, f(x)and g(x), and

How to determine if two functions are inverses calculator

then f(x) and g(x) are inverse functions.

Let's try this on an easy one that we know will work:


How to determine if two functions are inverses calculator


How to determine if two functions are inverses calculator


How to determine if two functions are inverses calculator

Yep, they are inverses, just like we thought!

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Find inverse function step by step

The calculator will find the inverse of the given function, with steps shown. If the function is one-to-one, there will be a unique inverse.

Your input: find the inverse of the function $$$y=\frac{x + 7}{3 x + 5}$$$

To find the inverse function, swap $$$x$$$ and $$$y$$$, and solve the resulting equation for $$$x$$$.

If the initial function is not one-to-one, then there will be more than one inverse.

So, swap the variables: $$$y=\frac{x + 7}{3 x + 5}$$$ becomes $$$x=\frac{y + 7}{3 y + 5}$$$.

Now, solve the equation $$$x=\frac{y + 7}{3 y + 5}$$$ for $$$y$$$.

$$$y=\frac{7 - 5 x}{3 x - 1}$$$

Answer

$$$y=\frac{7 - 5 x}{3 x - 1}$$$

Inverse function calculator helps in computing the inverse value of any function that is given as input. To recall, an inverse function is a function which can reverse another function. It is also called an anti function. It is denoted as:

f(x) = y ⇔ f− 1(y) = x

How to Use the Inverse Function Calculator?

This calculator to find inverse function is an extremely easy online tool to use. Follow the below steps to find the inverse of any function.

  • Step 1: Enter any function in the input box i.e. across “The inverse function of” text.
  • Step 2: Click on “Submit” button at the bottom of the calculator.
  • Step 3: A separate window will open where the inverse of the given function will be computed.

How to Find the Inverse of a Function?

To find the inverse of any function, first, replace the function variable with the other variable and then solve for the other variable by replacing each other. An example is provided below for better understanding.

Example: Find the inverse of f(x) = y = 3x − 2

Solution:

First, replace f(x) with f(y).

Now, the equation y = 3x − 2 will become,

x = 3y − 2

Solve for y,

y = (x + 2)/3

Thus, the inverse of y = 3x − 2 is y = (x + 2)/3/

Frequently Asked Questions on Inverse Function

How do you find the inverse of a function?

To find the inverse of a function, write the function y as a function of x i.e. y = f(x) and then solve for x as a function of y.

What is the inverse of 6?

The inverse of 6 is ⅙. For any function “x”, the inverse will be “1/x”.