
Vertex!
The function f(x) = x^2  18x + 83 achieves its minimum at (9,2). If g(x) = f(x4)3, where is the vertex of g(x)?
This problem is driving me crazy!!!!
Okay so far I've tried to do the shift thing. which I got: (13,1)
Then I tried to just plug it in as is and squared the equation which got me: (13,4)
Other answers I've tried: (5,3) (13,2) (5,5) and so many others lols, on the record it said I've tried 28 times.
Seriously, this seems like the EASIEST problem but I just can't get the right answer, please help.
I won't even get full credit anymore but I realllyyyy want to know HOW to get the answer. Thank you~

Re: Vertex!
$\displaystyle g(x)=(x4)^218(x4)+80$
Hence :
$\displaystyle g(x)=x^226x+168$
Vertex is given by :
$\displaystyle V\left(\frac{b}{2a},\frac{D}{4a}\right)$
where :
$\displaystyle a=1 , b=26 , c=168 , D =b^24ac$

Re: Vertex!
hmmm, so the answer IS (13,1)? Xx...Great, now i gotta tell the teacher
[Update]
WOW, fail...the answer IS (13,1)... BUT turns out I had to put the answer in parentheses...maybe i should delete this thread.
God I want to kill myself T_T;;