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    IB Math AASL
    /
    Trig equations & identities
    /

    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.

    Trig equations & identities

    Video Reviews

    Watch comprehensive video reviews for Trig equations & identities, 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.

    Unit circleTrig functionsTrig equationsIdentitiesHL functionsHL Identities

    The video will automatically pause when it reaches a problem.

    sin²θ+cos²θ=1

    SL 3.6

    Remember that cosθ, sinθ are the base and height of a right angled triangle whose hypotenuse is 1, we can apply Pythagoras's Theorem and conclude:

    sin2θ+cos2θ=1📖


    Example

    Given that cosθ=−53​ and π≤θ≤2π, find sinθ.


    sin2θ+(−53​)2sin2θsinθ​=1=1−259​=2516​=±√2516​​=±54​​

    And since π≤θ≤2π, sinθ<0 so sinθ=−54​.

    sin²θ+cos²θ=1

    SL 3.6

    Remember that cosθ, sinθ are the base and height of a right angled triangle whose hypotenuse is 1, we can apply Pythagoras's Theorem and conclude:

    sin2θ+cos2θ=1📖


    Example

    Given that cosθ=−53​ and π≤θ≤2π, find sinθ.


    sin2θ+(−53​)2sin2θsinθ​=1=1−259​=2516​=±√2516​​=±54​​

    And since π≤θ≤2π, sinθ<0 so sinθ=−54​.

    Unit circleTrig functionsTrig equationsIdentitiesHL functionsHL Identities