How do you find the domain and range of f(x)=3/(x-1)f(x)=3x1?

1 Answer
May 9, 2017

x inRR,x!=1

y inRR,y!=0

Explanation:

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

"solve" x-1=0rArrx=1larrcolor(red)" excluded value"

"domain is " x inRR,x!=1

"to find any excluded values for y"

"rearrange f(x), making x the subject"

y=3/(x-1)

rArry(x-1)=3

rArrxy-y=3

rArrx=(3+y)/y

"the denominator cannot be zero"

rArry=0larrcolor(red)" excluded value"

"range is " y inRR,y!=0