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    IB Math AASL
    /
    Counting & Binomials
    /

    Video

    Video Reviews

    Watch comprehensive video reviews for most units, 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.

    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.

    Binomial Coefficient nCr

    SL AA 1.9

    The number in the nth row and rth column of Pascal's triangle (the rows and columns start at zero) is denoted by nCr​, where 0≤r≤n. Alternative notations include

    nCr​=Crn​=(nr​)🚫

    This number can be calculated using the formula

    nCr​=r!(n−r)!n!​📖

    Notice, either using the formula or Pascal's Triangle that

    nC0​=n!n!​=1🚫

    and

    nC1​=1!⋅(n−1)!n!​=n🚫

    Example

    (73​)=3!⋅4!7!​=3⋅27⋅6⋅5​=35

    Binomial Coefficient nCr

    SL AA 1.9

    The number in the nth row and rth column of Pascal's triangle (the rows and columns start at zero) is denoted by nCr​, where 0≤r≤n. Alternative notations include

    nCr​=Crn​=(nr​)🚫

    This number can be calculated using the formula

    nCr​=r!(n−r)!n!​📖

    Notice, either using the formula or Pascal's Triangle that

    nC0​=n!n!​=1🚫

    and

    nC1​=1!⋅(n−1)!n!​=n🚫

    Example

    (73​)=3!⋅4!7!​=3⋅27⋅6⋅5​=35
    SL TheoryBinomial ProblemsCounting (HL)