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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.

    Solving cosθ=a

    SL 3.8

    Since cosθ represents the x-coordinate of a point on the unit circle, solving the equation

    cosθ=a

    is equivalent to drawing the line x=a, finding the intersections with the unit circle, and determining the angle of these intersections relative to the positive x-axis.


    This helps visualize all the possible solutions. For

    cosθ=a,0≤θ<2π

    the solutions are

    θ=cos−1(a),2π−cos−1(a)

    Powered by Desmos

    Solving cosθ=a

    SL 3.8

    Since cosθ represents the x-coordinate of a point on the unit circle, solving the equation

    cosθ=a

    is equivalent to drawing the line x=a, finding the intersections with the unit circle, and determining the angle of these intersections relative to the positive x-axis.


    This helps visualize all the possible solutions. For

    cosθ=a,0≤θ<2π

    the solutions are

    θ=cos−1(a),2π−cos−1(a)

    Powered by Desmos

    Unit circleTrig functionsTrig equationsIdentitiesHL functionsHL Identities