Intro to Functions Study Guide

Given f(x) =
2x² + 5x - 17, find f(-1). 

• f(-1) = -20

• f(-1) = -24

The function h(t) represents the height in inches of a plant after t weeks. What does the notation h(4) = 5 mean?

• After 5 week the plant is 4 inches tall

• The plant grows at a rate of 5/4 inch per week

• After 4 weeks the plant is 5 inches tall

• The plant grows at a rate of 1 inch per week

Derek works at Subway making $9.25 an hour.  The function d(x)=9.25x tells us how much money Derek makes after x hours of working.  What is the meaning of d(4)=37?

• After 4 hours of work, Derek makes $37.

• Derek needs $4 more to have $37 total.

• After working for 4 days, Derek makes $37 total.

• After 4 hours of work, Derek now makes $37 an hour instead of $9.25.

Ms. Brackemyer is collecting pencils.  The function p(x)=5x+12 tells us the total amount of pencils Ms. Brackemyer has after collecting for x number of days.  What is the meaning of p(8)=52?

• Ms. Brackemyer starts with 8 pencils and ends with 52.

• After 8 days, Ms. Brackemyer has 52 pencils.

• Ms. Brackemyer starts with 52 pencils and gets 4 more every day.

• Every day, Ms. Brackemyer gets 4 new pencils until she has 52.

What is the domain of the graph?

• 1≤ x ≤ 4

• 1 < x < 4

• 1≤ y ≤ 4

• 1 < y < 4

The function c(m) = 1.45m + 3.50 represents the cost of a taxi for m miles.
What does c(7) represent?

• cost of $7 to ride the taxi

• cost to ride 7 miles

• minimum distance to ride a taxi

• minimum cost of a taxi

The function c(m) = 1.45m + 3.50 represents the cost of a taxi for m miles.
What does c(m) represent?

• Total Cost of a taxi

• Total Miles in taxi

A company is selling bubble gum.  The function g(x)=3x+4 tells the company how much to charge if someone buys x packages of bubble gum.  Find g(8) and tell what it means within the context of the problem.

• g(8)=8.  This means that after 8 packages of gum, the company makes $8.

• g(8)=42.  This means that 8 packages of gum costs $42.

• g(8)=28.  This means that 8 packages of gum costs $28.

• g(8)=24.  This means that 8 packages of gum costs $24.

For the function {(0,1), (1,-3), (2,-4), (-4,1)}, write the domain and range.

• D: {1, -3, -4,}
  R: {0, 1, 2, -4}

• D:{-4, 0, 1, 2}
  R:{-4, -3, 1}

• D:{0, 1, 2, 3, 4}
  R:{1, -3, -4}

What is the domain?

• -4 < x ≤ 5

• -4 ≤ x < 5

• -3 < y < 3

• -3 ≤ y ≤ 3