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

2 Answers
MAXIMILIAN C.
Apr 13, 2018

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.

Jim G.
Apr 13, 2018

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]}

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