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    IB Math AAHL
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    Counting & Binomials
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    Counting & Binomials

    Skill Checklist

    See everything you need to know in this unit and with an interactive checklist to check your progress.

    Go to Checklist • 16 Skills

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    Problems

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    Lessons

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    Thumbnail for Pascal's Triangle and nCr

    Theoretical introduction to n​Cr​, or (nr​), and Pascal's triangle.

    Pascal's Triangle and nCr
    Thumbnail for Binomial Theorem

    Using nCr​ to expand binomials like (1+2x)7.

    Binomial Theorem (Plus Only)
    Thumbnail for Counting

    Using permutations & combinations alongside principles to count the ways things can be selected or arranged.

    Counting (Plus Only)
    Thumbnail for Counting with Restrictions

    Advanced techniques for scenarios with branches, negative counting, and permutations where items need to stay together / separate.

    Counting with Restrictions (Plus Only)

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    5 / 40 problems visible - Upgrade to view all problems

    IB: 4
    1

    !

    0 / 5

    In the expansion of (2x−a)6, the coefficient of x4 is 380​.

    Find the possible value(s) of a.

    [5]
    2

    !

    0 / 6

    In the expansion of (2x3+bx1​)8, the coefficient of x12 is 28.

    Find the value of b.

    [6]
    3

    0 / 5

    Find the number of distinct ways the letters in the word MISSISSIPPI can be arranged.

    [5]
    4

    0 / 5

    Expand (2x−3)4 in descending powers of x.

    [5]
    5

    !

    Plus

    0 / 4

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