Parent Functions – Examples, Properties and Types

When collaborating with functions and their graphs, you’ll observe how most functions’ graphs look alike and adhere to comparable patterns. Therefore, functions sharing the same degree will conform to a similar contour and share the same parent functions.

This description outlines what parent functions are. We use parent functions to lead us in graphing functions in the same family. In this short article, we will certainly:

Evaluate all the unique parent functions (you may have already run into some before).

Learn exactly how to recognize the parent function that a function belongs to.

The ability to identify and graph functions utilizing their parent functions can support us in recognizing functions more.

More about the parent function

Now that we understand precisely how important it is to grasp the different kinds of parent functions, it allows the first to start to recognize what parent functions are and how their family members’ functions are affected by their properties.

Parent function meaning

Parent functions are the simplest type of offered parent functions. It is a group of functions that include a similar significant degree and, subsequently, the same form for their graphs.

The graph over programs four graphs that display the U-shaped graph we call the parabola. Since they all share the very same highest possible degree of 2 and the same form, we can organize them as one family member of function. Which family do they belong to?

These four quadratic functions and their most accessible form would be y = x2. For this reason, the parent function for this family member is y = x2.

Read Also: All about Factoring Trinomials Calculator

Since parent functions are the most straightforward kind of a provided group of functions, they can quickly offer a concept of how a proposed function from the same family members would resemble.

What are the different sorts of parent functions?

It’s time to rejuvenate our understanding of functions and learn about brand-new functions. As we have discussed, acquainting ourselves with the known parent functions will help us recognize and graph functions much better and faster.

Why do we not start with the ones we might have identified in the past?

The very first four parent functions include polynomials with increasing degrees. Let’s observe how their graphs act and note the respective parent functions’ domain and range.

Constant Functions

Constant functions are functions that are specified by their particular constant, c. You will find horizontal lines for all constant functions as their graph and content only a constant as its term.

Real numbers will be the domain of all constant functions, and y = c as their range. They additionally each have a y-intercept at (0, c).

An object’s activity at remainder is a fine example of a constant function.

Linear Functions

Linear functions have a general form of y = a + bx and x as the term with the highest degree. As a graph, all linear functions have a straight line.

The parent function of linear is y = x, which travels through the beginning. The domain and also series of all linear functions are all real numbers.

These functions are relationships between 2 objects that are linearly proportional to each other.

Quadratic Functions

Quadratic functions are functions with two as their highest level. All quadratic functions come back with a parabola as their graph. As reviewed in the previous section, y = x2 is the parent function of a quadratic function.

The parent function y = x2 vertex lies at the beginning. Moreover, it has a domain of all real numbers and a variety of [0, ∞). Observe that this function increases when x declares and reduces while x is unfavorable.

An excellent application of quadratic functions is projectile activity. We can observe an object’s projectile activity by graphing the quadratic function that represents it.

Cubic Functions

Allow’s go on to the parent function of polynomials, with three as its most extraordinary degree. Cubic functions have a standard parent function of y = x3. This function is increasing throughout its domain.

Just like both earlier parents, the graph of y = x3 also reaches the origin. Its range and domain are both (-∞, ∞) or all real numbers.

Absolute Value Functions

The absolute value functions y =|x |. The parent function’s graph shows that absolute value functions are expected to return V-shaped graphs.

The vertex of y =|x|is located at the origin also. Given that it has a domain at (- ∞, ∞) and expands on both ends of the x-axis, y=|x|. You cannot have negative absolute values. Therefore, the parent function has a range of [0, ∞).

We use these functions to highlight that a function’s value always needs to declare.

Radical Functions

The two most frequently made use of radical functions are the square root and also cube root functions.

The square root function has the parent function of y = √ x. Its graph shows that its x and y values cannot be negative.

It implies that the domain and also range of y = √ x are both [0, ∞). The starting factor or vertex of the parent function is also discovered at the origin. The parent function y = √ x is likewise boosting throughout its domain.

Let’s now research the parent function of cube root functions. Comparable to the square root function, its parent function is revealed as y = ∛ x.

The graph entails that the parent function has a range and domain of (- ∞, ∞). We can also observe that y = ∛ x is boosting throughout its domain.

Exponential Functions

These functions in their exponent have algebraic expressions in their exponent. You can express their parent function as y = bx, where b can be any non-zero constant. The graph of the parent function, y = ex, is shown, and from it, we can see that it will certainly never amount to 0.

And when x = 0, y goes at y = 1 through the y-axis. We can also witness that the parent function is never listed under the y-axis. Hence, its range is (0 ∞). Its domain, nonetheless, can be all genuine numbers. We can likewise see that this function extends throughout its domain.

The most typical applications of exponential functions are modelling population growth and substance passion.

Logarithmic Functions

The inverse functions of exponential functions are Logarithmic functions. Its parent function is y = logb x, where b is a non-zero favourable constant. Allow’s to see the graph chart when b = 2.

Similar to the exponential function, we can observe that x can never be equal to or less than zero for y = log2x. For this reason, its domain is (0 ∞). Its range, nevertheless, includes all real numbers. We can also observe that this function is rising throughout its domain.

We utilize logarithmic functions to design, for instance, earthquake magnitude in nature. We also use it when calculating the half-life decay rate in chemistry and physics.

Reciprocal Functions

These functions are functions that contain a consistent numerator and x as its. Its parent function is y = 1/x.

As seen from its graph chart, y and x can never equal zero. This suggests that its range and domain are (0, – ∞) U (0, ∞). We can likewise see that the function is lowering throughout its domain.

There are various other parent functions throughout this article with functions and graphs. Yet, these eight parent functions are the most frequently used and discussed.

You can even summarize what you’ve learned up until now by developing a table exhibiting all the parent functions’ properties.

The best strategy to calculate the parent function

What happens if we’re offered a function or its graph and need to identify its parent function? We can do this by keeping each function’s essential properties in mind and determining which of the parent graphs we’ve discussed suit the one provided.

Right here are some guide inquiries that can help us:

  • What is the function’s highest possible level?
  • Does it include a cube root or a square root?
  • Is the function available at the exponent or common denominator?
  • Is the function’s graph decreasing or enhancing?
  • What is the function’s domain or range?

If we address several of these questions by examination, we will likely have the ability to deduce our options and ultimately identify the parent function.


Which of the complying with functions do not come from the provided family of functions?

y = -2×2 + 3x – 1

y = 5×2

y = (x – 1)(x + 1)

y = x(3×2)


The function y = 5×2 has the highest possible degree of two. Hence, it is a quadratic function. This implies that its parent function is y = x2. The very same goes for y = -2 x2 + 3x– 1. From this, we can verify that we’re looking at a family of quadratic functions.

Using the distinction of perfect squares on the 4th choice, we have y = x2– 1. This is likewise a quadratic function. That leaves us with the third alternative.

When expanded, y = x(3×2) comes to be y = 3×3, which also reveals that it has three as its highest degree. Thus, it can’t be part of the provided family of functions.