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    IB Math AAHL
    /
    Proof and Reasoning
    /

    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.

    Proof and Reasoning

    Video Reviews

    Watch comprehensive video reviews for Proof and Reasoning, 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.

    Timeline

    DIRECT PROOF (SL + HL)

    Deductive Proof

    00:40

    Problem

    03:04

    Problem

    07:34

    HL TERMS & DEFINITIONS

    Even and Odd Numbers

    10:39

    Problem

    12:55

    Divisibility

    14:26

    Prime Numbers

    17:11

    CONTRADICTION (HL)

    Proof by contradiction

    23:07

    Problem

    28:00

    Rational Numbers

    35:49

    Problem

    40:51

    Counterexamples

    44:40

    Problem

    46:55

    PROOF BY INDUCTION

    How induction works

    53:24

    Problem

    57:27

    Simple equality

    1:10:33

    Induction with divisibility

    1:13:01

    Problem

    1:17:10

    Induction with inequalities

    1:20:39

    Problem

    1:25:52

    Induction with summation

    1:35:37

    Problem

    1:38:01

    Induction with derivatives

    1:43:08

    Problem

    1:46:18

    Direct proof (SL + HL)HL Terms & DefinitionsContradiction (HL)Proof by induction

    The video will automatically pause when it reaches a problem.

    Direct proof (SL + HL)HL Terms & DefinitionsContradiction (HL)Proof by induction