Question 1015736
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I am not understanding the (f o g) problems this one for sure
f(x)=3x and g(x)=9x^2+1
with (f o f)(1)
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<pre>
Hello,

to find (fog)(x), you need to substitute the expression for g(x) into f(x) instead of x, 
and after that to make all necessary calculations / transformations.


It is the general rule, and below I show you how it works in your case.


Your function f(x) = 3*x simply multiplies x by 3.
Now, substitute g(x) into f instead of x. You will get


(fog)(x) = f( (g(x) ) = 3*g(x) = {{{3*(9x^2+1)}}} = {{{27x^2 + 3}}}.


That is all. You just found (f0g)(x). It is (fog)(x) = {{{27x^2 + 3}}}.


Now, when they ask you about (fog)(1), simply substitute x=1 into 

(fog)(x) = {{{27x^2 + 3}}}.

You will get (fog)(x) = {{{27*1^2 + 3}}} = 27 + 3 = 30.

It is your answer.
</pre>

One more notice. What I wrote above, relates to (fog)(x) and (fog)(1).


It is not about (fof)(x) and not about (fof)(1).


Next time formulate your question more clearly please.
Here you mixed two questions: about (fog)(x) and about (fof)(x).