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GCSE AQA Further Maths Level 2 HELP!!!! watch

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    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
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    (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
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    (Original post by buttered_peanut)
    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
    Thanks
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    Good Luck everyone with the exam tommorrow
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    How was the exam everyone!
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    (Original post by Hassan_786)
    How was the exam everyone!
    I though some questions were fairly straightforward but about 3/4 totally stumped me really hope I get an A tbh!! How did you find it? What did you get for the circle theorem one?
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    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!


    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)
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    (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
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    (Original post by Zippyzazu)
    I though some questions were fairly straightforward but about 3/4 totally stumped me 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
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    (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!
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    (Original post by Hassan_786)
    Yes please
    Hi! do you remember any answers? If so, please add them!
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    work out what u don't know then google it!
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    i got 27/512 for the last one ?
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    (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!
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    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😭


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    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?


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    (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+
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    (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😭


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    i did the same
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    (Original post by Hassan_786)
    i did the same
    Oh dear, since it was only 2 marks we probably won't get any method marks either :/


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    (Original post by Saywhatyoumean)
    Oh dear, since it was only 2 marks we probably won't get any method marks either :/


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    are u sure we lose the marks
 
 
 
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