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    IB Math AASL
    /
    2D & 3D Geometry
    /

    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.

    2D & 3D Geometry

    Video Reviews

    Watch comprehensive video reviews for 2D & 3D Geometry, 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.

    Right TrianglesNon right trianglesCircles, arc, radians3D solids

    The video will automatically pause when it reaches a problem.

    Cosine rule

    SL Core 3.2

    The cosine rule is a generalization of Pythagoras' theorem for non-right-angled triangles. It states that

    c2=a2+b2−2abcosC📖


    The cosine rule is primary used when we

    • know two sides and the angle between them, and want to find the third side,

    • know all three sides and want to find an angle.


    Example

    Triangle ABC has [AB]=3, [BC]=4 and [AC]=5. Find the angle C.


    The angle C is between the sides [BC] and [AC] so

    [AB]2 9 cosC​=[BC]2+[AC]2−2[BC]⋅[AC]cosC =16+25−2⋅4⋅5cosC =4032​⇒C≈36.9°​

    Cosine rule

    SL Core 3.2

    The cosine rule is a generalization of Pythagoras' theorem for non-right-angled triangles. It states that

    c2=a2+b2−2abcosC📖


    The cosine rule is primary used when we

    • know two sides and the angle between them, and want to find the third side,

    • know all three sides and want to find an angle.


    Example

    Triangle ABC has [AB]=3, [BC]=4 and [AC]=5. Find the angle C.


    The angle C is between the sides [BC] and [AC] so

    [AB]2 9 cosC​=[BC]2+[AC]2−2[BC]⋅[AC]cosC =16+25−2⋅4⋅5cosC =4032​⇒C≈36.9°​
    Right TrianglesNon right trianglesCircles, arc, radians3D solids