You are Here: Home >< Maths

# Home study is proving futile. is this right? watch

1. I want to learn as-level maths, self-taught, at home. So, I decided to buy " Cambridge A level mathematics for aqa student book 1 (AS/year 1)".

this is for the new linear spec I've been hearing about.

I've come from gcse, obviously, which I'm fairly competent in.

they offer two quick examples of an equation on the first page, which I can do. then in the exercise part to part 1, with said examples, they throw this at me:

X3 - 4x2 - 3x + 18 = (x+a)(x+b)2 for all x. Find the value of a and b.

Am I supposed to know how to do this? Because it offers no prior knowledge to something like this on the first page.

What am I missing here?

the worked example, which is supposed to of "taught me" how to do this is as follows:
2x^2 + 12x - 3 = a(x + p)^2 + q . find the values of a,p and q.

bit different, right? or is it just me.

I have no idea how to do this. I've been on it a week trying to understand it. is there a better of learning this, because, far as I can tell, this book assumes a great deal of knowledge about the reader.
2. That's higher level gcse maths, you should probably start there first.
3. (Original post by Azzyh)
I want to learn as-level maths, self-taught, at home. So, I decided to buy " Cambridge A level mathematics for aqa student book 1 (AS/year 1)".

this is for the new linear spec I've been hearing about.

I've come from gcse, obviously, which I'm fairly competent in.

they offer two quick examples of an equation on the first page, which I can do. then in the exercise part to part 1, with said examples, they throw this at me:

X3 - 4x2 - 3x + 18 = (x+a)(x+b)2 for all x. Find the value of a and b.

Am I supposed to know how to do this? Because it offers no prior knowledge to something like this on the first page.

What am I missing here?

the worked example, which is supposed to of "taught me" how to do this is as follows:
2x^2 + 12x - 3 = a(x + p)^2 + q . find the values of a,p and q.

bit different, right? or is it just me.

I have no idea how to do this. I've been on it a week trying to understand it. is there a better of learning this, because, far as I can tell, this book assumes a great deal of knowledge about the reader.
Two tricks you can use are:
1: Multiply out:

then compare the coeffifients on the powers of x.

2: Substitute in small values for x and if the sum is 0 (say x=a), then you found a factor (x-a).
then you can use long division to find a quadratic which you may then be able to factorise further.

Spoiler:
Show

Constant term of the polynomial is 18. By comparing coefficients:

### Related university courses

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:
Updated: October 31, 2017
Today on TSR

### He broke up with me because of long distance

Now I'm moving to his city

### University open days

1. Norwich University of the Arts
Thu, 19 Jul '18
2. University of Sunderland
Thu, 19 Jul '18
3. Plymouth College of Art
Thu, 19 Jul '18
Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams