How do you find the domain of sqrt(x+4)?

2 Answers
Mar 26, 2018

The domain is x >= 4

Explanation:

Since square roots are only defined when the expression under the square root is non-negative, to find the domain we set the expression under the square root greater than or equal to zero:

x - 4 >= 0
x >= 4

Mar 26, 2018

[-4,oo)

Explanation:

Firstly you know that there can't be a negative under a square root sqrt(-1) any negative leads to the function being undefined

So when x+4<0 i.e. it is lower than zero you know there is no domain

So when x+4>=0 the domain exists so it eixsts when x>=-4

So the domain is [-4,oo)