MHB Calculating the Derivative of a Function Using the Chain Rule

[karush]

find $F'(x)$
$$F(x)=(7x^6+8x^3)^4$$
chain rule
$$4(7x^6+8x^3)^3(42x^5+24x^2)$$
factor
$$4x^3(7x^3+8)^3 6x^2(7x^3+4)$$

ok W|A returned this but don't see where the 11 came from
$$24 x^{11} (7 x^3 + 4) (7 x^3 + 8)^3$$

 

[topsquark]

find $F'(x)$
$$F(x)=(7x^6+8x^3)^4$$
chain rule
$$4(7x^6+8x^3)^3(42x^5+24x^2)$$
factor
$$4x^3(7x^3+8)^3 6x^2(7x^3+4)$$

ok W|A returned this but don't see where the 11 came from
$$24 x^{11} (7 x^3 + 4) (7 x^3 + 8)^3$$

Look at your first factor:
[math]\left ( 7x^6 + 8 x^3 \right ) ^3 = ( x^3 ( 7 x^3 + 8 ) )^3 = (x^3)^3 (7 x^3 + 8 )^3[/math]

Don't worry. It's an easy mistake to make and a pain in the pahtootie to find when you check your work.

-Dan

 

[karush]

yeah that was kinda behind the bushes...