How to find domain for #f(x)=sqrt(x+4)#?

2 Answers
Sep 25, 2015

Domain #x>=-4#

Explanation:

The domain is the set of #x# values that your function can accept. In this case you have a square root that cannot accept a negative argument.
So you may say that must be:
#x+4>=0#
or
#x>=-4# meaning that as long as #x# is equal or bigger than #-4# it is ok!

Refer to explanation

Explanation:

When you have a function with formula

#f(x)=sqrt(g(x))# where g(x) is a polynomial then for the function f
to be defined we need the condition that #g(x)>=0#.

Hence in our case #g(x)=x+4# hence #x+4>=0# or #x>=-4#

So the domain is #D(f)=[-4,+oo)#