Question

Find the range of f(x)=-2x-5 for domain -2, -1, 1, 2

Answer 1

{-1, -3, -7, -9} is the range of the function f(x)

Explanation:

Domain is the set of all complete possible values of x variable.

Range is the set of all values of f(x)

Given the function:

`f(x) = -2x-5` .....[1]

Domain: {-2, -1, 1, 2}

For x = -2,

Substitute in [1] we have

`f(-2) = -2(-2)-5 = 4-5 = -1`

Similarly ,

For x = -1

`f(-1) = -2(-1)-5 = 2-5 = -3`

For x = 1:

`f(1) = -2(1)-5 = -2-5 = -7`

For x = 2

`f(2) = -2(2)-5 = -4-5 = -9`

Therefore, the range of f(x) = {-1, -3, -7, -9}

Answer 2

Range = {-2(-2) - 5, -2(-1) - 5, -2(1) - 5, -2(2) - 5} = {4 - 5, 2 - 5, -2 - 5, -4 - 5} = (-1, -3, -7, -9}