Question #810cb

2 Answers
Apr 17, 2017

They are not inverses

Explanation:

One way to tell if two functions are inverses of each other is to take one equation, say, #f(x)# and replace all the #x#s with the function of #g(x)#. If the two are inverses of each other, they should simplify to #x#. If they simply to anything other than just #x#, they are not inverses.

#f(g(x))#
#6(6x-1)+1#
#36x-6+1#
#36x-5#
That doesn't equal #x#, so they're not inverses.

Apr 17, 2017

If they are inverses, then the following must be true:

#f(g(x))=x# and #g(f(x)) = x#

Explanation:

Given: #f(x)= 6x+1; g(x)=6x-1#

Substitute #g(x)# for every x in #f(x)#

#f(g(x)) = 6g(x)+1#

Substitute the #6x-1# for #g(x)# on the right:

#f(g(x)) = 6(6x-1)+1#

#f(g(x)) = 36x-6+1#

#f(g(x)) = 36x-5#

We may stop and declare that they are not inverses