Question

find dy/dx if y=4(x^2-5x)(9+x^7)

Answer 1

u=x^2-5x
v=9+x^7
d(uv)/dx=uv'+u'v

Answer 2

remember to multiply by scalar 4 after getting your answer.

Answer 3

alternative way is to expand out using foil, but imo that's a waste of time

Answer 4

Use the chain rule 4 is a constant so keep that in front. \[4\frac{ dt }{ dx } = (x^{2} -5x)\frac{ d }{ dx }(9+x^{7}) + (9+x^{7})\frac{ d }{ dx }(x^{2} +5x)\]

Answer 5

that t is a y.

Answer 6

thank you so much!

Answer 7

to me, I will do something like