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    IB Math AASL
    /
    Sequences & Series
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    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.

    Sequences & Series

    Video Reviews

    Watch comprehensive video reviews for Sequences & Series, 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.

    SequencesSeriesPaper 1 ProblemsFinancePaper 2 Problems

    The video will automatically pause when it reaches a problem.

    Finite Geometric Series

    SL Core 1.3

    The sum of the first n terms in a geometric sequence is given by:

    Sn​=r−1u1​(rn−1)​=1−ru1​(1−rn)​📖


    Example

    A geometric sequence has u1​=27 and r=31​. Find the sum of the first 4 terms.

    S8​=1−31​27⋅(1−341​)​    ​=32​27⋅(1−811​)​ =32​27−31​​ =23⋅27−3⋅31​​=40​

    Finite Geometric Series

    SL Core 1.3

    The sum of the first n terms in a geometric sequence is given by:

    Sn​=r−1u1​(rn−1)​=1−ru1​(1−rn)​📖


    Example

    A geometric sequence has u1​=27 and r=31​. Find the sum of the first 4 terms.

    S8​=1−31​27⋅(1−341​)​    ​=32​27⋅(1−811​)​ =32​27−31​​ =23⋅27−3⋅31​​=40​
    SequencesSeriesPaper 1 ProblemsFinancePaper 2 Problems