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    IB Math AASL
    /
    Counting & Binomials
    /

    Video

    Video Reviews

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    Not your average video:

    Interactive Problems: Solve problems alongside the video with step-by-step guidance and detailed solutions.

    Exam Preparation: Complete unit reviews designed for final exam preparation with all key concepts covered systematically.

    Expert Teaching: High-quality instruction from Perplex co-founder James Mullen with clear explanations, worked examples, and exam tips.

    Counting & Binomials

    Video Reviews

    Watch comprehensive video reviews for Counting & Binomials, designed for final exam preparation. Each video includes integrated problems you can solve alongside detailed solutions.

    Not your average video:

    Interactive Problems: Solve problems alongside the video with step-by-step guidance and detailed solutions.

    Exam Preparation: Complete unit reviews designed for final exam preparation with all key concepts covered systematically.

    Expert Teaching: High-quality instruction from Perplex co-founder James Mullen with clear explanations, worked examples, and exam tips.

    Not your average video:

    Interactive Problems: Solve problems alongside the video with step-by-step guidance and detailed solutions.

    Exam Preparation: Complete unit reviews designed for final exam preparation with all key concepts covered systematically.

    Expert Teaching: High-quality instruction from Perplex co-founder James Mullen with clear explanations, worked examples, and exam tips.

    SL TheoryBinomial ProblemsCounting (HL)

    The video will automatically pause when it reaches a problem.

    The expansion of (a+b)ⁿ

    SL AA 1.9

    The binomial theorem allows us expand expressions of the form (a+b)n:

    (a+b)n=an+nC1​an−1b1+nC2​an−2b2+⋯📖

    or in summation form:

    (a+b)n=r=0∑n​(nr​)an−rbr🚫

    Example

    The expansion of (3+x)4 is

    34+(41​)33⋅x1+(42​)32⋅x2+(43​)31⋅x3+(44​)x4
    =
    81+4⋅27x+6⋅9x2+4⋅3x4+x4
    =
    81+108x+54x2+12x3+x4

    The expansion of (a+b)ⁿ

    SL AA 1.9

    The binomial theorem allows us expand expressions of the form (a+b)n:

    (a+b)n=an+nC1​an−1b1+nC2​an−2b2+⋯📖

    or in summation form:

    (a+b)n=r=0∑n​(nr​)an−rbr🚫

    Example

    The expansion of (3+x)4 is

    34+(41​)33⋅x1+(42​)32⋅x2+(43​)31⋅x3+(44​)x4
    =
    81+4⋅27x+6⋅9x2+4⋅3x4+x4
    =
    81+108x+54x2+12x3+x4
    SL TheoryBinomial ProblemsCounting (HL)