Question

when you derive for example
5ln(X^2 +2) why isnt product rule used? my buddy here says five is just a multiplier for derivative of lnf(x), why?

Answer 1

You can use that rule but it's not necessary.

Answer 2

where would you apply the product rule here?

Answer 3

isnt it 5*lnf(x)

Answer 4

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Answer 5

beats me dude

Answer 6

You can apply that rule like this:
\[\frac{d}{dt} 5\times \ln{(x^2+2)}+5\times\frac{d}{dt}\ln{(x^2+2)}\]

Answer 7

oh! ok. got it. they cansel.

Answer 8

...

Answer 9

Usually it's better to use the chain rule when you have a product of two non constant functions.

Answer 10

If you apply it to a product of a constant and a function you'll be loosing your time, but your result will be correct