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    • Thread Starter
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    Hi All,

    Would anyone be able to help me with this C2, June 2015 Question please?

    3. f(x)= 6X (Cb.) + 3X (Sq.) + Ax + B.

    Given that when f(x) is divided by (x+1) the remainder is 45,

    a. Show that B - A = 48. (2 Marks)

    I was able to do this question.


    Given also that (2x + 1) is a factor of f(x),

    b. Find the value of A and the value of B. (4 Marks)

    If possible could somebody help me with question b please.

    Many Thanks
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    (Original post by AgonizedGod)
    Hi All,

    Would anyone be able to help me with this C2, June 2015 Question please?

    3. f(x)= 6X (Cb.) + 3X (Sq.) + Ax + B.

    Given that when f(x) is divided by (x+1) the remainder is 45,

    a. Show that B - A = 48. (2 Marks)

    I was able to do this question.


    Given also that (2x + 1) is a factor of f(x),

    b. Find the value of A and the value of B. (4 Marks)

    If possible could somebody help me with question b please.

    Many Thanks
    What have you tried for part b?
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    If (2x+1) is a factor of f(x) then f(-1/2)=0.
    Do the same thing you do for the first part of the question to find an equation in terms of a and b.
    Then it's just normal simultaneous equation to find a and b and hence f(x).
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    (Original post by SeanFM)
    What have you tried for part b?
    (Original post by B_9710)
    If (2x+1) is a factor of f(x) then f(-1/2)=0.
    Do the same thing you do for the first part of the question to find an equation in terms of a and b.
    Then it's just normal simultaneous equation to find a and b and hence f(x).
    I've gotten to the point myself where I managed to get: -1/2A + B = 0 and the B - A = 48 from part a. Am I right in assuming that I need to use these for my simultaneous equations?
    • Very Important Poster
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    (Original post by AgonizedGod)
    I've gotten to the point myself where I managed to get: -1/2A + B = 0 and the B - A = 48 from part a. Am I right in assuming that I need to use these for my simultaneous equations?
    Correct. :borat:
    • Thread Starter
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    Thanks for the help both of you, I was able to get a final answer of A= -96 and B= -48
 
 
 
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