Notation of a Function

šŸ†Practice representations of functions

The notation of a function actually refers to determining the "name" of the function.

It is customary to symbolize a function using letters from the Latin alphabet when the two most common notations are:

  • yy
  • f(x)f(x)

(Of course, similar notations can also be used).

The - inside parentheses expresses that it is an independent variable of the function and the function's dependency ( or ) on it. xx,yy,ff

Notation of a Function

Start practice

Test yourself on representations of functions!

einstein

Is the given graph a function?

ā€“4ā€“4ā€“4ā€“3ā€“3ā€“3ā€“2ā€“2ā€“2ā€“1ā€“1ā€“1111222333444ā€“2ā€“2ā€“2ā€“1ā€“1ā€“1111222000

Practice more now

In the blog of Tutorela you will find a variety of articles with interesting explanations about mathematics


Examples and exercises with solutions of function notation

Exercise #1

Is the given graph a function?

ā€“7ā€“7ā€“7ā€“6ā€“6ā€“6ā€“5ā€“5ā€“5ā€“4ā€“4ā€“4ā€“3ā€“3ā€“3ā€“2ā€“2ā€“2ā€“1ā€“1ā€“1111222333444555666777ā€“4ā€“4ā€“4ā€“3ā€“3ā€“3ā€“2ā€“2ā€“2ā€“1ā€“1ā€“1111222333000

Video Solution

Step-by-Step Solution

It is important to remember that a function is an equation that assigns to each element in domain X one and only one element in range Y

We should note that for every X value found on the graph, there is one and only one corresponding Y value.

Therefore, the graph is indeed a function.

Answer

Yes

Exercise #2

Is the given graph a function?

ā€“7ā€“7ā€“7ā€“6ā€“6ā€“6ā€“5ā€“5ā€“5ā€“4ā€“4ā€“4ā€“3ā€“3ā€“3ā€“2ā€“2ā€“2ā€“1ā€“1ā€“1111222333444555666777ā€“4ā€“4ā€“4ā€“3ā€“3ā€“3ā€“2ā€“2ā€“2ā€“1ā€“1ā€“1111222333000

Video Solution

Step-by-Step Solution

It is important to remember that a function is an equation that assigns to each element in domain X one and only one element in range Y

Let's note that in the graph:

f(0)=2,f(0)=āˆ’2 f(0)=2,f(0)=-2

In other words, there are two values for the same number.

Therefore, the graph is not a function.

Answer

No

Exercise #3

Is the given graph a function?

ā€“7ā€“7ā€“7ā€“6ā€“6ā€“6ā€“5ā€“5ā€“5ā€“4ā€“4ā€“4ā€“3ā€“3ā€“3ā€“2ā€“2ā€“2ā€“1ā€“1ā€“1111222333444555666777ā€“4ā€“4ā€“4ā€“3ā€“3ā€“3ā€“2ā€“2ā€“2ā€“1ā€“1ā€“1111222333000

Video Solution

Step-by-Step Solution

It is important to remember that a function is an equation that assigns to each element in domain X one and only one element in range Y

We should note that for every X value found in the graph, there is one and only one corresponding Y value.

Therefore, the graph is indeed a function.

Answer

Yes

Exercise #4

Determine whether the following table represents a function

XY02468-3-3-3-3-3

Video Solution

Step-by-Step Solution

It is important to remember that a constant function describes a situation where as the X value increases, the function value (Y) remains constant.

In the table, we can see that there is a constant change in the X values, specifically an increase of 2, and the Y value remains constant.

Therefore, according to the rule, the table describes a constant function.

Answer

Yes

Exercise #5

Which of the following equations corresponds to the function represented in the graph?

ā€“8ā€“8ā€“8ā€“7ā€“7ā€“7ā€“6ā€“6ā€“6ā€“5ā€“5ā€“5ā€“4ā€“4ā€“4ā€“3ā€“3ā€“3ā€“2ā€“2ā€“2ā€“1ā€“1ā€“1111222333444555666777888ā€“5ā€“5ā€“5ā€“4ā€“4ā€“4ā€“3ā€“3ā€“3ā€“2ā€“2ā€“2ā€“1ā€“1ā€“1111222333444000

Video Solution

Step-by-Step Solution

Let's use the below formula in order to find the slope:

m=y2āˆ’y1x2āˆ’x1 m=\frac{y_2-y_1}{x_2-x_1}

We begin by inserting the known data from the graph into the formula:

(0,āˆ’2),(āˆ’2,0) (0,-2),(-2,0)

m=āˆ’2āˆ’00āˆ’(āˆ’2)= m=\frac{-2-0}{0-(-2)}=

āˆ’20+2= \frac{-2}{0+2}=

āˆ’22=āˆ’1 \frac{-2}{2}=-1

We then substitute the point and slope into the line equation:

y=mx+b y=mx+b

0=āˆ’1Ɨ(āˆ’2)+b 0=-1\times(-2)+b

0=2+b 0=2+b

Lastly we combine the like terms:

0+(āˆ’2)=b 0+(-2)=b

āˆ’2=b -2=b

Therefore, the equation will be:

y=āˆ’xāˆ’2 y=-x-2

Answer

y=āˆ’xāˆ’2 y=-x-2

Join Over 30,000 Students Excelling in Math!
Endless Practice, Expert Guidance - Elevate Your Math Skills Today
Test your knowledge
Start practice