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# Could they ever ask you to differentiate/integrate.... Watch

1. If they gave question stating something like:

$y= \frac{3x^{3}-1}{x-2}$

"Find dy/dx."

How would I solve this. I don't know how I would put this into index form without fractions first.

This is in case it comes in a C2 or even a C1 paper.

Thanks
2. (Original post by wrestlingfan55)
If they gave question stating something like:

$y= \frac{3x^{3}-1}{x-2}$

"Find dy/dx."

How would I solve this. I don't know how I would put this into index form without fractions first.

This is in case it comes in a C2 or even a C1 paper.

Thanks
do you cover the quotient rule or product rule in your core modules?
3. I pretty sure that would only be asked in C3/4.
4. (Original post by davros)
do you cover the quotient rule or product rule in your core modules?
Err nope.

I only know that if you have two fractions to add you find the LCM and cross multiply for the numerator (but that's GCSE Maths). But this one is just a single fraction, so I have no idea how I'd tackle this sort of question.
5. (Original post by wrestlingfan55)
Err nope.

I only know that if you have two fractions to add you find the LCM and cross multiply for the numerator (but that's GCSE Maths). But this one is just a single fraction, so I have no idea how I'd tackle this sort of question.
In that case you're probably "safe" from this sort of question!

If you're interested, google "product rule" or "quotient rule" or get hold of a decent A level book that covers these rules - they're not too difficult to learn
6. you could express it as a product of (3xcubed-1) x (x-2)^(-1) and do it that way for differentiation (which means it could well come up in C2 exams), integration-wise at least C4 most likely FP3. (assuming you are taking Edexcel)
7. (Original post by davros)
In that case you're probably "safe" from this sort of question!
8. (Original post by wrestlingfan55)
If they gave question stating something like:

$y= \frac{3x^{3}-1}{x-2}$

"Find dy/dx."

How would I solve this. I don't know how I would put this into index form without fractions first.

This is in case it comes in a C2 or even a C1 paper.

Thanks
This is not a C1 or C2 skill so you will not be asked anything like this.
9. (Original post by Mr M)
Pah! I can't be doing with this modular nonsense - why can't people just learn Maths like they used to
10. (Original post by davros)
Pah! I can't be doing with this modular nonsense - why can't people just learn Maths like they used to
Well they will soon!
11. (Original post by natninja)
you could express it as a product of (3xcubed-1) x (x-2)^(-1) and do it that way for differentiation (which means it could well come up in C2 exams), integration-wise at least C4 most likely FP3. (assuming you are taking Edexcel)
That still requires knowledge of the product rule.
12. If you're doing OCR Maths (I don't know about MEI) then unless there's a way to cancel that down to a single line, you would only ever be asked it in core 3 or 4
13. You may be asked to do this if the numerator is divisible by the denominator, so that you get a polynomial which you can differentiate. In the case you gave there is a remainder when you divide the numerator by the denominator and your expression will contain a term which you will not be able to differentiate yet.
14. Differentiation: use either quotient rule: u/v = (v.du/dx - u.dv/dx)/v2

or convert to product: (3x3-1)(x-2)-1 and use product rule:
u.v = u.dv/dx + v.du/dx

If it was an integration question then the numeratoir is of higher order than the denominator so must be converted to a partial fraction first before integrating.

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