Question 127634
{{{f(x) = x/(x+t)}}}  {{{g(x)= x^3}}}


Is the denominator {{{x+t}}} or {{{x+1}}}?  I'm going to assume a typo in the original function statement since you go on about {{{x+1}}}.


The two denominators are {{{x+1}}} and {{{1}}}.  Since they have no factors in common, the common denominator is the product of the two:  {{{(x+1)(1)=x+1}}},


So:

{{{(x/(x+1))+(x^3)/1}}}



{{{(x+(x^3(x+1)))/(x+1)}}}


{{{(x^4+x^3+x)/(x+1)}}}




{{{f(f(x))= root(3,root(3,x-1)) -1}}}  is your answer...but you missed it by THAT much.


{{{f(f(x))= root(3,root(3,x-1)-1)}}}.  See the difference?  You just had a misplaced bracket.