You are Here: Home >< Maths

Announcements Posted on
TSR's new app is coming! Sign up here to try it first >> 17-10-2016
1. How do you do Q2 on JAN 11 OCR CORE 1?

http://www.ocr.org.uk/Images/65379-q...hematics-1.pdf
2. Repeat answer to repeat question.

Well I do not know which explanations you have not understood. However since it is an identity (true for all x).
Substitute in x=0 to get 5p=2q and also some other value of x to get another equation.

If you factorise both sides fully you find a common factor of (x+2) on both sides which cancels to give (x-p)(2x+5)=(x-2)(2x+q) which makes life easier.
Once you sub in x=2, the RHS is zero and the LHS is fairly easy.

Next use x=-5/2 which makes the LHS zero and the RHS fairly easy

The key point is knowing what an identity is. You can put in any value of x you like and choosing a sensible value will give you a relatively straightforward thing to do.
3. The markl scheme expects you to expand both sides and compare coefficents, this gets you a pair of simultaneous equations in p & q leading to p=2 and q=5. If you need some help on the algebra for this then come back.

## Register

Thanks for posting! You just need to create an account in order to submit the post
1. this can't be left blank
2. this can't be left blank
3. this can't be left blank

6 characters or longer with both numbers and letters is safer

4. this can't be left empty
1. Oops, you need to agree to our Ts&Cs to register

Updated: May 18, 2016
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Today on TSR

### How does exam reform affect you?

From GCSE to A level, it's all changing

Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read here first

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams