How do you find the domain of #f(x)=(x-3)/(x+4)#?

2 Answers
Apr 13, 2018

Answer:

Domain is all real numbers except #x=-4#

Explanation:

The only limitation on the domain in this equation is undefined answers. Therefore, the limitation can be described by (denominator)=0 or in this case #x+4=0#, so #x# cannot equal #-4#.

Apr 13, 2018

Answer:

#x inRR,x!=-4#

Explanation:

The denominator of f(x) cannot be zero as this would make f(x) undefined. Equating the denominator to zero and solving gives the value that x cannot be.

#"solve "x+4=0rArrx=-4larrcolor(red)"excluded value"#

#"domain is "x inRR,x!=-4#

#x in(-oo,-4)uu(-4,+oo)larrcolor(blue)"in interval notation"#
graph{(x-3)/(x+4) [-10, 10, -5, 5]}