Question 116512
The notation should be {{{f(g(x))}}}.  Notice that the {{{g(x)}}} replaces the {{{x}}} in {{{f(x)}}}, which is what you do with the two function definitions.


{{{f(x)=2/(x-8)}}} and {{{g(x)=7/4x}}}


{{{f(g(x))=2/(g(x)-8)=2/((7/4x)-8)}}}


Of course, now you have to do some simplification
{{{f(g(x))=2/((7-32x)/4x)}}}
{{{f(g(x))=2*(4x/(7-32x))}}}
{{{f(g(x))=(8x/(7-32x))}}}


Super-Double-Plus Extra Credit:  The domain of {{{f(x)}}} is all reals {{{x<>8}}}, and the domain of {{{g(x)}}} is all reals {{{x<>0}}}.  What is the domain of {{{f(g(x))}}}?