Function Notation

Function Notation is when the "y" in a function is replaced with f(x).

Write the following in Function Notation

• y=4x+3
• y=-x-10
• y=3x-8
• y=16-x
• 5x+2=y
• y=2x+1

f(x) is read as "f of x" and it does not mean “f times x”

"f" can actually be any variable.
Example: g(x), h(x)

When the x is replaced by a number like f(3) the 3 replaces x in the function

f(3) = x +2 is the same as f(3) = 3 + 2.
Now we can solve that f(3)=5

Solve using f(x)=4x+3

• Find f(2)
• Find f(-5)
• Find f(10)
• Find f(1)
• Find f(7)
• Find f(-2)

Solve Using g(x)=x^2-3

• Find g(-4)
• Find g(12)
• Find g(4)
• Find g(-1)
• Find g(5)

Solve using h(x)=4x-6x

• Find h(10)
• Find h(-7)
• Find h(13)
• Find h(8)

Combining Functions

If you have two functions, with different variables, you can still combine them. For example, f(x)+g(x)= (f+g)(x).

f(x)=4x+3
g(x)=x^2-3
(f+g)(x)=(4x+3)+(x^2-3)
Simplify

Combine the following functions

• f(x)=4x+3, g(x)=x^2-3, h(x)=4x-6x
• g(x)-h(x)
• h(x)+f(x)
• f(x)-g(x)