Question 216194
Here's the basic idea: 


Step 1) Plug in {{{x=1/2}}} into {{{g(x)}}}. The result/output will be a number


Step 2) Take the result of step 1 and plug that number into 'x' of {{{f(x)}}}. You will once again get a number as a result.


Step 3) Take the answer from step 2 and plug it into {{{h(x)}}}. The result that you get here will be the answer (provided there are no errors).