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    Hiya, im stuck on a C2 polynomial question. It reads:

    "Divide -3x4 + 8x2 + 13x - 10 by (x - 2)"

    Thanks!
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    (Original post by JamesNeedHelp2)
    Hiya, im stuck on a C2 polynomial question. It reads:

    "Divide -3x4 + 8x2 + 13x - 10 by (x - 2)"

    Thanks!
    There are various methods

    Long division
    Equating coefficients

    What have you tried?
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    (Original post by TenOfThem)
    There are various methods

    Long division
    Equating coefficients

    What have you tried?
    Long division, but i cant get past the first step. thank you
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    (Original post by JamesNeedHelp2)
    Long division, but i cant get past the first step. thank you
    Did you remember to put the 0x^3 in
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    (Original post by TenOfThem)
    Did you remember to put the 0x^3 in
    no i did not. i will work it out and put my working on here. Maybe you can help me then? thanks.
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    (Original post by TenOfThem)
    Did you remember to put the 0x^3 in
    "Divide -3x4 + 8x2 + 13x - 10 by (x - 2)"

    Where do i put the 0x3 in? is it supposed to look like this..."-3x4 + 0x3 + 8x2 + 13x - 10 by (x - 2)"

    -3x3 - 5x2 - 2x - 9

    (x- 2) x (-3x3) = -3x4 + 6x3

    (-3x4 + 0x3) - (-3x4 + 6x3) = (-3x4 + 0x3) + (3x4 - 6x3) = -5x3 + 8x2

    (x- 2) x ( -5x2) = -5x3 + 10x2

    (-5x3 + 8x2) + (5x3 - 10x2) = -2x2 + 13x

    (x- 2) x (-2x) = -2x2 + 4x

    (-2x2 + 4x) - (-2x2 + 13x) = -9x - 10

    Answer; -3x3 - 5x2 - 2x - 9
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    Put your terms in descending powers of x, so swap the first two
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    (Original post by offhegoes)
    Put your terms in descending powers of x, so swap the first two
    ahaaa that makes sense. thank you
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    (Original post by offhegoes)
    Put your terms in descending powers of x, so swap the first two
    "-3x4 + 0x3 + 8x2 + 13x - 10 by (x - 2)"

    -3x3 - 5x2 - 2x - 9

    (x- 2) x (-3x3) = -3x4 + 6x3

    (-3x4 + 0x3) - (-3x4 + 6x3) = (-3x4 + 0x3) + (3x4 - 6x3) = -5x3 + 8x2

    (x- 2) x ( -5x2) = -5x3 + 10x2

    (-5x3 + 8x2) + (5x3 - 10x2) = -2x2 + 13x

    (x- 2) x (-2x) = -2x2 + 4x

    (-2x2 + 4x) - (-2x2 + 13x) = -9x - 10

    Answer; -3x3 - 5x2 - 2x - 9
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    (Original post by JamesNeedHelp2)
    "Divide -3x4 + 8x2 + 13x - 10 by (x - 2)"

    Where do i put the 0x3 in? is it supposed to look like this..."-3x4 + 0x3 + 8x2 + 13x - 10 by (x - 2)"

    -3x3 - 5x2 - 2x - 9

    (x- 2) x (-3x3) = -3x4 + 6x3

    (-3x4 + 0x3) - (-3x4 + 6x3) = (-3x4 + 0x3) + (3x4 - 6x3) = -5x3 + 8x2

    (x- 2) x ( -5x2) = -5x3 + 10x2

    (-5x3 + 8x2) + (5x3 - 10x2) = -2x2 + 13x

    (x- 2) x (-2x) = -2x2 + 4x

    (-2x2 + 4x) - (-2x2 + 13x) = -9x - 10

    Answer; -3x3 - 5x2 - 2x - 9
    Let me see if I can find your error

    0- -6 is not -5 in your x^3
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    (Original post by TenOfThem)
    Let me see if I can find your error

    0- -6 is not -5 in your x^3
    surely,-6x3 + x3 = -5x3?
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    (Original post by JamesNeedHelp2)
    surely,-6x3 + x3 = -5x3?
    Well, yes, -6+1=-5

    But you had 0 and needed to subtract -6 and 0--6 = 6
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    (Original post by TenOfThem)
    Well, yes, -6+1=-5

    But you had 0 and needed to subtract -6 and 0--6 = 6
    aaaah i see, im so retarded. Appreciated.
 
 
 
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