-3(X-4)^2+13

The Anonymous answer is almost correct, except that he/she should have added 13 rather than subtracting it.

-3(X-4)^2+13 =-3(x^2-8x+16)-13=-3x^2+24x-48-13=-3x^2+24x-61

-3(X-4)^2+13

-3(x-4)^15

-3x^15*12^15

So that wouldbe your simplified version... or you could write it as

-3x^15*15,407,021,574,586,368

I see...I think I misinterpreted the question.

I thought it was 

-3(X-4)²⁺¹³ 

but I think you meant

-3(X-4)²+13 

My bad.

Ninja, you did misinterprete the question (exponents come before addition, remember pedmas) but even if it was to the power of 15 you still got the answer wrong.  Try thinking about it for a while.  I would like you to 'see' for yourself why it is wrong.   There would probably be an x¹⁵ term,  x¹⁴ term,  x¹³ term,   all the way down to a constant term.  (A couple might cancel out)  If you want to discuss it further that is fine.