How do you find the inverse of f(x)=3x+1?

2 Answers
Jun 7, 2018

f^-1(x)=(x-1)/3

Explanation:

Let's start by replacing f(x) with y. We now have

y=3x+1

Let's switch x and y to get

x=3y+1

Let's solve for y now. We can start by subtracting 1 from both sides to get

3y=x-1

Dividing both sides by 3, we get

y=(x-1)/3

This is our inverse, so we can replace y with f^-1(x):

f^-1(x)=(x-1)/3

Hope this helps!

Jun 7, 2018

f^-1(x)=1/3(x-1)

Explanation:

"let "y=3x+1

"rearrange making x the subject"

3x=y-1

x=1/3(y-1)

rArrf^-1(x)=1/3(x-1)