please help I will fan and medal!
Find the coefficient of the squared term in the simplified form for the second derivative, f "(x) for f(x) = (x^3 + 3x^2 + 3)(3x^3 − 6x^2 − 8x + 1) . Use the hyphen symbol, -, for negative values.

Question

please help I will fan and medal!
Find the coefficient of the squared term in the simplified form for the second derivative, f "(x) for f(x) = (x^3 + 3x^2 + 3)(3x^3 − 6x^2 − 8x + 1) . Use the hyphen symbol, -, for negative values.

chris215 · Answer

i got 108?

solomonzelman · Answer

I don't think so.

solomonzelman · Answer

It might be a pain in the neck to expand it, but once you expand it to find the second derivative and then the coefficient of x^2 shouldn't be much trouble.

solomonzelman · Answer

Oh, you don't need to expand.

michele_laino · Answer

Hint:
I got this expression for $f(x)$:
$f(x)=3x^6+3x^5-26x^4-14x^3-15x^2-24x+3$

anonymous · Answer

f"x=90x^4+60x^3-312x^2-84x-15

anonymous · Answer

That should be the answer

anonymous · Answer

after taking two derivatives of what Michele Lanio got

solomonzelman · Answer

You know that the second derivative of ax^4 will yield the coefficient you need.
What is the ax^4 in this case?

(x^3)•(-8x)
      +
(-6x^2)•(3x^2)
______________
-8x^4-18x^4=-26x^4

g(x)=-26x^4
g''(x)=(-26•3•4)x^2

solomonzelman · Answer

You can ignore the rest of the terms in the f(x), just the products of those that give x^4.