SOLUTION: PLEASE HELP!! :) Let f(x)=x(squared)-1 and g(x)=4x+7. Find (f+g)(1/2).

Algebra ->  Rational-functions -> SOLUTION: PLEASE HELP!! :) Let f(x)=x(squared)-1 and g(x)=4x+7. Find (f+g)(1/2).      Log On


   

Question 273226: PLEASE HELP!! :)
Let f(x)=x(squared)-1 and g(x)=4x+7. Find (f+g)(1/2).
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Recall that %28f%2Bg%29%28x%29=f%28x%29%2Bg%28x%29


%28f%2Bg%29%28x%29=f%28x%29%2Bg%28x%29 Start with the given equation


%28f%2Bg%29%28x%29=x%5E2-1%2B4x%2B7 Plug in f%28x%29=x%5E2-1 and g%28x%29=4x%2B7


%28f%2Bg%29%281%2F2%29=%281%2F2%29%5E2-1%2B4%281%2F2%29%2B7 Plug in x=1%2F2


%28f%2Bg%29%281%2F2%29=1%2F4-1%2B4%281%2F2%29%2B7 Square 1%2F2 to get 1%2F4


%28f%2Bg%29%281%2F2%29=1%2F4-1%2B2%2B7 Multiply


%28f%2Bg%29%281%2F2%29=33%2F4 Combine like terms.


So the answer is %28f%2Bg%29%281%2F2%29=33%2F4