Question

Could anyone help me find the derivative (dy/dx) of this equation?

Answer 1

\[y = e^{-6x} * \cos(-8x)\]

Answer 2

as you can see, it is a product of two factors, so which rule will we apply?

Answer 3

Product Rule?

Answer 4

perfect, do you know how to use it?

Answer 5

Is it f '(x)g(x)+f(x)g'(x)

Answer 6

exactly.. in this case:
f = e^(-6x)
f' =
g = cos(-8x)
g' =

Answer 7

are you getting it?

Answer 8

so f' would be 1/e^6 and g' would be -8sin(8x)?

Answer 9

f = e^(-6x)
f' = -6e^(-6x) (use chain rule)
g = cos(-8x)
g' = 8sin(-8x) (chain rule again)

Answer 10

how's it coming?

Answer 11

I got it, thank you