SOLUTION: given f(x)=sqrt x+3 and g(x)=6x find f(g(x)) i.e.(fog)(x) and find (fog)(1) I know that you need to replace the x in sqrt of x +3 so it would read sqrt 6x+3 then would I chan

Algebra ->  Rational-functions -> SOLUTION: given f(x)=sqrt x+3 and g(x)=6x find f(g(x)) i.e.(fog)(x) and find (fog)(1) I know that you need to replace the x in sqrt of x +3 so it would read sqrt 6x+3 then would I chan      Log On


   

Question 224515: given f(x)=sqrt x+3 and g(x)=6x find f(g(x)) i.e.(fog)(x) and find (fog)(1)
I know that you need to replace the x in sqrt of x +3 so it would read sqrt 6x+3
then would I change that to (6x+3)^2 =36x^2+36x+9.
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Your first part is correct. f(g(x)) means to substitute g(x) = 6x into the formula for f, so f%28g%28x%29%29=sqrt%286x%2B3%29+. However, what you did next was NOT correct. You have a SQUARE ROOT, NOT a SQUARE! Do NOT square it!!!

f(g(1)) means to substitute 1 in place of the x.

This would be f%28g%281%29%29=+sqrt%286%2B3%29=sqrt%289%29=3

f(g(1)) = 3

R^2