Perplex
  • Lessons
  • Problems
  • Speed Run
  • Practice Tests
  • Skill Checklist
  • Review Videos
  • All Content
  • Landing Page
  • Sign Up
  • Login
  • Perplex
    IB Math AAHL
    /
    Transformations & asymptotes
    /

    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.

    Transformations & asymptotes

    Video Reviews

    Watch comprehensive video reviews for Transformations & asymptotes, 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.

    HL content

    The video will automatically pause when it reaches a problem.

    Rationals with quadratic denominator

    AHL 2.13

    When a rational function is of the form

    f(x)=cx2+dx+eax+b​

    There will be vertical asymptotes when the quadratic cx2+dx+e=0.


    The horizontal asymptote will simply by y=0 since cx2 dominates ax when x is very large.


    Additionally, there will be an x-intercept at x=−ab​, when the numerator changes sign.


    Note that if the numerator and denominator share a root (ie x=−ab​ is a root of the denominator), then there will only be one asymptote and a "hole" on the x-axis. This has never showed up on exams.


    Example

    Sketch the graph of y=x2−x−6x−1​.


    The denominator is (x−3)(x+2), which is zero when x=3 and x=−2.


    The numerator is 0 when x=1 (negative to the left and positive to the right). When x<−2, the function is negative (plug in −3)


    So we plot the asymptotes x=3 and x=−2, and start tracing from the negative side of the x-axis. At each vertical asymptote the sign will change, and we have an x-intercept at 1.


    Powered by Desmos


    Rationals with quadratic denominator

    AHL 2.13

    When a rational function is of the form

    f(x)=cx2+dx+eax+b​

    There will be vertical asymptotes when the quadratic cx2+dx+e=0.


    The horizontal asymptote will simply by y=0 since cx2 dominates ax when x is very large.


    Additionally, there will be an x-intercept at x=−ab​, when the numerator changes sign.


    Note that if the numerator and denominator share a root (ie x=−ab​ is a root of the denominator), then there will only be one asymptote and a "hole" on the x-axis. This has never showed up on exams.


    Example

    Sketch the graph of y=x2−x−6x−1​.


    The denominator is (x−3)(x+2), which is zero when x=3 and x=−2.


    The numerator is 0 when x=1 (negative to the left and positive to the right). When x<−2, the function is negative (plug in −3)


    So we plot the asymptotes x=3 and x=−2, and start tracing from the negative side of the x-axis. At each vertical asymptote the sign will change, and we have an x-intercept at 1.


    Powered by Desmos


    HL content