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

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Answer 1 · 2018-06-07T20:16:45

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

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!

Answer 2 · 2018-06-07T20:18:43

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

#"let "y=3x+1#

#"rearrange making x the subject"#

#3x=y-1#

#x=1/3(y-1)#

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