Question

Find the range of each function for the domain {-4, -2, 0, 1.5, 4}. f(x) = 5x^2 + 4

Answer 1

Substitute x with the members of the domain.
f(x) = 5x² + 4

Substitute with the domain of -4
f(x) = 5x² + 4
f(-4) = 5(-4)² + 4
f(-4) = 5(16) + 4
f(-4) = 80 + 4
f(-4) = 84

Substitute with the domain of -2
f(x) = 5x² + 4
f(-2) = 5(-2)² + 4
f(-2) = 5(4) + 4
f(-2) = 20 + 4
f(-2) = 24

Substitute with the domain of 0
f(x) = 5x² + 4
f(0) = 5(0)² + 4
f(0) = 5(0) + 4
f(0) = 0 + 4
f(0) = 4

Substitute with the domain of 1.5
f(x) = 5x² + 4
f(1.5) = 5(1.5)² + 4
f(1.5) = 5(2.25) + 4
f(1.5) = 11.25 + 4
f(1.5) = 15.25

Substitute with the domain of 4
f(x) = 5x² + 4
f(4) = 5(4)² + 4
f(4) = 5(16) + 4
f(4) = 80 + 4
f(4) = 84

The range of the function for those domain is {4, 24, 15.25, 84}