Adding, Subtracting Functions

As well as Multiplying and Dividing Them!

Operations with Functions Worksheet (25 question pdf with answer key on this page's topic)
Functions Home Multiply and Dividing Functions | Functions in Math | Composition of functions

Adding and Subtracting Functions

There is nothing tricky about adding or subtracting functions. To add, or subtract, functions, first evaluate the given functions then perform the indicated operation.

Example Problem

f(x) = 2x
g(x) = 3x+1
What is f(3) + g(4) ?
Step 1: evaluate the individual functions
- f(3) = 2×3 = 6
- g(4) = 3×4 +1 = 13
Step 2: Add the values that your functions produced
- f(3) + g(4) = 6 + 13 = 19

Practice Problems

Functions:
f(x) = 3x-1
g(x) = 3x³-1

Evaluate f(6) + g(2)

Answer

Functions:
f(x) = 4x – 1
g(x) = x²

Evaluate f(5) - g(3)

Answer

Multiplying and Dividing Functions

Multiplying and Dividing functions works the same as adding and subtracting functions. Simply evaluate the individual functions then perform the indicated multiplication or division.

Example Problem

f(x) = 3x

g(x) = 5x+2

What is f(8) ÷ g(2) ?

Step 1: evaluate the individual functions

f(8) = 3 × 8 = 24
g(2) = 5 ×2 +2 = 12

Step 2: Divide the values that your functions produced

f(8) ÷ g(2) = 24 ÷ 12 = 2

Practice Problems

Functions:
j(x) = 5x
p(x) =x+1

Evaluate j(7) ÷ p(4)

Answer

Functions:
f(x) = 3x+2
k(x) = 5x+1

Evaluate f(4) × k(2)

Answer

fraction games onlinemathgames.comlaw of sinesambiguous case of the law of sines