Domain and Range

Question

Find the domain and range of the function

 

y={x+1 if -5<x<0

      x²    if 0≤x≤5

Answer 1

Hi Naomi,

 

Domain refers to the values of x and range refers to the y values of a function using those xs.

For y = x + 1

domain: all real numbers in (-5, 0)

To find the range, we check the lower and upper bounds of the domain. 

x = -5, y = -4

x = 0, y = 1

So, the range is all real numbers in (-4, 1)

 

for y = x^2 

domain: [0, 5]

 

x = 0, y = 0

x = 5, y = 25

range is all real numbers in [0, 25]

Please note that I used [ to indicate "equal to".