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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.

    Finding angles in right angled triangles

    SL Core 3.2

    If we know the value of sinθ, cosθ or tanθ in a right angled triangle, we can find θ using an inverse trigonometric function on a calculator. These functions are sin−1, cos−1 and tan−1 and satisfy

    sin−1(sinθ)=θcos−1(cosθ)=θtan−1(tanθ)=θ​

    whenever θ<90°, which is always true in a right angled triangle.


    Example

    Find θ in the triangle below.

    Powered by Desmos

    The side opposite θ has length 4, and the hypotenuse has length 5. So

    sinθ=54​⇒θ=sin−1(54​)≈53.1°

    Finding angles in right angled triangles

    SL Core 3.2

    If we know the value of sinθ, cosθ or tanθ in a right angled triangle, we can find θ using an inverse trigonometric function on a calculator. These functions are sin−1, cos−1 and tan−1 and satisfy

    sin−1(sinθ)=θcos−1(cosθ)=θtan−1(tanθ)=θ​

    whenever θ<90°, which is always true in a right angled triangle.


    Example

    Find θ in the triangle below.

    Powered by Desmos

    The side opposite θ has length 4, and the hypotenuse has length 5. So

    sinθ=54​⇒θ=sin−1(54​)≈53.1°
    Right TrianglesNon right trianglesCircles, arc, radians3D solids