Question

Calculate the derivative using the appropriate rule or combination of rules.
f (x) = 5x^2(4 + 5x^-1)

Answer 1

factor in the 5x^2 and you get
20x^2 + 25x
then take derivative
f'(x) = 40x + 25

Answer 2

i don't think that is right.
you need to use the product rule and the chain rule.. you can't just use the power rule to solve for this.

Answer 3

you could do that too but its more work, its easier to just factor it in and use power rule for it

Answer 4

@jayz657 is correct

Answer 5

so you got 5x^2(d/dx 4+5x^-1)+(4+5x^-1)(d/dx 5x^-1)

Answer 6

oh okay i see what you mean by factoring it in!

Answer 7

i thought you meant just do the power rule straight from it.

Answer 8

haha yea i just manipulated the problem a bit to make it easier to take derivative thats all