To find the x intercept of a function

Step 1

Plug the value x = 0 into the rational function and determine the value of f(x) to find the y-intercept of the function.

For example, plug x = 0 into the rational function f(x) = (x^2 – 3x + 2) / (x – 1) to get the value (0 – 0 + 2) / (0 – 1), which is equal to 2 / -1 or -2 (if the denominator is 0, there is a vertical asymptote or hole at x = 0 and therefore no y-intercept).

The y-intercept of the function is y = -2.

Step 2

Factor the numerator of the rational function completely. In the above example, factor the expression (x^2 – 3x + 2) into (x – 2)(x – 1).

Step 3

Set the factors of the numerator equal to 0 and solve for the value of the variable to find the potential x-intercepts of the rational function.

How to find x and y intercepts of a rational function

In the example, set the factors (x – 2) and (x – 1) equal to 0 to get the values x = 2 and x = 1.

Step 4

Plug the values of x you found in Step 3 into the rational function to verify that they are x-intercepts.

X-intercepts are values of x that make the function equal to 0. Plug x = 2 into the example function to ge

y intercept rational function calculator

finding x and y intercepts in rational functions