Evaluating Functions

If a question asks you to find f(2), what does that mean?

• Let x = 2

• Let y = 2

If f(x) = 2x + 1, what would be your first step to find f(1)?

• Plug a 1 in for all the x's

• Set the function equal to 1

• Only plug a 1 into the left side

• Only plug a 1 into the right side

If f(x) = 2x+1, what would the function look like once you substitute in a 1 to find f(1)?

• f(x) = 21+1

• f(1) = 2 (1) + 1

• f(1) = 2x (1) + 1

If f(x) = 2x + 1, find f(1).

• f(1) = 1

• f(1) = 4

• f(1) = 0

• f(1) = 3

Evaluate f(-2) if f(x) = x + 3

• -1
• 1
• 5
• -5

g(x) = 3x + 1
g(10) = ______

• 14
• 31
• 15
• -31

For the function f(x) = -3(x-1) find f(0).

• 0
• -3
• 3
• -1