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    Hello!
    Could someone please help me on q 9 on the posted picture (binomial expansion). n=8 but idk how to get that.
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    (Original post by Jahayna)
    Hello!
    Could someone please help me on q 9 on the posted picture (binomial expansion). n=8 but idk how to get that.
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    The coefficient of x^2 (in terms of n) = 7.

    Can you write that equation?
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    (Original post by BuryMathsTutor)
    The coefficient of x^2 (in terms of n) = 7.

    Can you write that equation?
    What do you mean?
    I thought of it that way but got stuck:

    Y * (x/2)^2 = 7x^2
    So y= 14
    So 14 must be the 3rd digit of the row n on pascals triangle
    So
    1
    n
    14
    But idk how to find n afterwards
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    Wait nvm i dont think thats right
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    (Original post by Jahayna)
    What do you mean?
    I thought of it that way but got stuck:

    Y * (x/2)^2 = 7x^2
    So y= 14
    So 14 must be the 3rd digit of the row n on pascals triangle
    So
    1
    n
    14
    But idk how to find n afterwards
    First of all (x/2)^2 = x^2/4.

    You would be better off writing nC2 rather than Y.
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    I really dont get it sorry.
    Could you please send me your working out if you can?
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    (Original post by Jahayna)
    I really dont get it sorry.
    Could you please send me your working out if you can?
    Here are some brief notes, followed by an example similar to your problem.
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