Understanding functions

A quadratic function is graphed on the grid.

Which answer choice best represents the domain and range of the function?

Identify the domain:

 $f\left(x\right)=\ -2\left(x+1\right)^2+5$  

•  $\left(-\infty,\infty\right)$  

•  $\left(-\infty,5\right)$  

•  $\left(5,\infty\right)$  

•  $\left(-\infty,1\right)$  

 A set of weights includes a 4lb barbell and 6 pairs of weight plates. If pair of weight plates are 20lbs. If x pairs of plates are added to the barbell, the total weight of the barbell in plates can be represented by the function $f\left(x\right)=20x+4$  

What is the range for this situation?

• {1, 2, 3, 4, 5, 6}

• {4, 24, 44, 64, 104, 124}

• {0, 2, 4, 6}

• {4, 44, 84, 124}

What are the domain restrictions for Problem 4?

•  $y\ne4$ 

•  $y\ne-1,\ 4$ 

•  $y\ne2,\ \pm4$ 

•  $y\ne0,\ 2,\ \pm4$ 

Determine the domain and range of the function

• Domain: All real numbers, Range: All real numbers

• Domain: x ≥ -4, Range: All real numbers

• Domain: All real numbers, Range: y ≥ -4

• Domain: -1 ≤ x ≤ 5, Range: y ≥ -4

Find the domain of the function. f(x) = x /2x+4

• x cannot equal to 2

• x cannot equal to 4

• x cannot equal to -2

• All real numbers

Leslie's car travels about 25 miles per gallon of gas. Her car needs 14 gallons of gas to be full. This is represented by the function  $g\left(x\right)=25x$ , for x gallons of gas. What is a reasonable domain?

• $x\ge25$

• $0\le y\le14$

• $x\le14$

• $0\le x\le14$

• ℝ

• [-6, ∞)

• (-∞, 6]

• [-4, ∞)

Find the domain for the function. f(x)= 2x -1 / 3x + 6

• x cannot equal to 2

• x cannot equal to -2

• x cannot equal to 3

• All real numbers

• All real numbers