Finding domain and range

Question

f(x)= -sqroot x+3

Answer 1

The domain this list of all x values you can plug in to the equation to get a real number. Therefore the two most important things to look for when finding domain are fractions (because a denominator cannot be zero) and square roots (because the value under the square root must be positive). 

 

Your problem has has no fractions so we don't have to worry about denominators. That leaves square roots. 

 

To to determine the domain, take the expression under the square root and set it ≥ 0, then solve for x. 

 

EXAMPLE 1:

g(x)=√(x) +1

    (x) is under the square root so x≥ 0 this is our domain

 

EXAMPLE 2:

h(x)=√(x +1)
(x+1) is under the square root so x+1 ≥ 0

Solve for x: x ≥ -1

this is our domain. 

 

Please let let me know if you have any questions.