Define functions of x

Question

Determine if the following equations define the functions of x:

 

a. y=√x+5

 

b. x²+y²=5

 

Answer 1

a)

 

Solve the following inequality.

 

x + 5 ≥ 0

 

The value of x you solve for is the domain.

 

 

b)

 

This is a circle with centerpoint at (0, 0) and radius of √5.

 

√5 ≈ 2.23

 

The domain is all real numbers between -√5 and √5, including -√5 and √5.