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C3 Differentiation

Not a question on how to do something, but rather, how do you know when to do what? like when to use product rule or quotient rule?

Like I understand the cases when you can't use it, but how do you know which is the best one to use as I could use certain ones with both?

I hope you understand what I'm trying to say?
Let f(x) and g(x) be two functions. If we have a function of the form f(x)g(x) then product rule. If we have a function of the form f(x)/g(x) then quotient rule.
Reply 2
Original post by mathematigeek
Let f(x) and g(x) be two functions. If we have a function of the form f(x)g(x) then product rule. If we have a function of the form f(x)/g(x) then quotient rule.


Yes I understand that, but my point is I could make F(x)/G(x) to F(x)(G(X))^-1 and use product rule, and sometimes it is in fact easier than using quotient rule.
Original post by Xphoenix
Not a question on how to do something, but rather, how do you know when to do what? like when to use product rule or quotient rule?

Like I understand the cases when you can't use it, but how do you know which is the best one to use as I could use certain ones with both?

I hope you understand what I'm trying to say?


Product rule, used when two functions are multiplied together, hence product.

Quotient rule, used when one function is divided by another. Basically, if you see a dividing line, use the latter.
Original post by Xphoenix
Yes I understand that, but my point is I could make F(x)/G(x) to F(x)(G(X))^-1 and use product rule, and sometimes it is in fact easier than using quotient rule.

So do what's easier.. but dont be surprised if you lose marks in an exam for using the same technique over and over even when its obvious by the set out of the function which is the intended method.

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