Competition - post a photo you've taken of nature >>

GCSE AQA Further Maths Level 2 HELP!!!!

Scroll to see replies

Need help on comleting the square!!!!!

Exam is tomorrow!!!!!!!!

The question is:

Work out the values of a,b and c such that
2x^+6x+7=a(x+b)^+c

please show me how to do it

thankssssss

Reply 41

buttered_peanut

Original post by Hassan_786

Need help on comleting the square!!!!!

Exam is tomorrow!!!!!!!!

The question is:

Work out the values of a,b and c such that
2x^+6x+7=a(x+b)^+c

please show me how to do it

thankssssss

With these, I got taught to treat it like any other equation and expand both sides, so...

1) a(x+b)^+c expands to
- a(x^+2bx+b^)+c
- ax^+2abx+a(b^)+c

2) Then compare this to the original;
2x^+6x+7 = ax^+2abx+a(b^)+c

3) Then split this into its own sections to compare;
- x^; 2x^ = ax^ so we can see that a=2

- nx; 6x = 2abx
Divide both sides by x and 2
3 = ab
We already know that a=2 so divide by 2.
b=1.5

- n; 7 = a(b^)+c
Square the value of b.
b^ = 1.5^ = 2.25
Times by a
a2.25 = 4.5
7 = 4.5+c
Subtract 4.5
c=2.5

4) Substitute back into the original equation to check...
2(x+1.5)^+2.5
2(x^+3x+2.25)+2.5
2x^+6x+7 = The original equation

a=2
b=1.5
c=2.5

Reply 42

Hassan_786

Original post by buttered_peanut

Thanks

Reply 43

Amen786

Good Luck everyone with the exam tommorrow :biggrin:

Reply 44

Hassan_786

How was the exam everyone!

Reply 45

Zippyzazu

Original post by Hassan_786

How was the exam everyone!

I though some questions were fairly straightforward but about 3/4 totally stumped me :frown:

really hope I get an A tbh!! How did you find it? What did you get for the circle theorem one?

Reply 46

Stillreading

I thought it was ok actually! The y=2x one baffled me at first, but I got it in the end! Should we make a mark scheme? I know not many people took it, but it might be worth it! Please add to it if you remember anything! :smile:

1. 10
2. 2
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14. y=2x proof
15.
16. 1/512 or 27/512
Can't remember which question numbers:

(x+1)^2+ (y-4)^2=25 circle equation (radius 5)

(107^2 - 93^2) = 2040

graph one with three points: (x+5) x=0 (x-3)
b= ? c= 15 (i think)

(edited 10 years ago)

Reply 47

Hassan_786

Original post by economicsrocks

I thought it was ok actually! The y=2x one baffled me at first, but I got it in the end! Should we make a mark scheme? I know not many people took it, but it might be worth it!

1. 10
2. 2
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14. y=2x proof
15.
16. 1/512
Can't remember which question numbers:

(x+1)^2+ (y-4)^2=25 circle equation (radius 5)
(107^2 - 93^2) = 2040

Yes please

Reply 48

Hassan_786

Original post by Zippyzazu

I though some questions were fairly straightforward but about 3/4 totally stumped me :frown:

really hope I get an A tbh!! How did you find it? What did you get for the circle theorem one?

yeah i though it wasn't too bad...what did you get for the graph question f(x) write the 3 points?
Also what did u get for the last question

Reply 49

Stillreading

Original post by Hassan_786

yeah i though it wasn't too bad...what did you get for the graph question f(x) write the 3 points?
Also what did u get for the last question

the graph one was (x+5) x=0 (x-3) that's what I got, but i don't know if it's right!

Reply 50

Stillreading

Original post by Hassan_786

Yes please

Hi! do you remember any answers? If so, please add them! :smile:

Reply 51

Sock Amoeba

work out what u don't know then google it!

Reply 52

Nerd44

i got 27/512 for the last one ?

Reply 53

Stillreading

Original post by Nerd44

i got 27/512 for the last one ?

haha oops i got 1/512

at least i'll get method marks!

Reply 54

Saywhatyoumean

For the linear factors question I didn't put x+5 I just wrote 5, do I lose marks for this?

I probably do I don't know what I was thinking😭

Posted from TSR Mobile

Reply 55

Saywhatyoumean

Also, as this paper was easier than last years do you think grade boundaries will be considerably higher?

I'm aiming for an A* which was around 70% in last years right?

Posted from TSR Mobile

Reply 56

Hassan_786

Original post by economicsrocks

the graph one was (x+5) x=0 (x-3) that's what I got, but i don't know if it's right!

Did you have to put x+

Reply 57

Hassan_786

Original post by Saywhatyoumean

For the linear factors question I didn't put x+5 I just wrote 5, do I lose marks for this?

I probably do I don't know what I was thinking😭

Posted from TSR Mobile

i did the same :frown:

Reply 58

Saywhatyoumean