Sine, cosine, tangent

  • Bend
    problem

    Bend

    Age
    16 to 18
    Challenge level
    1 out of 3
    What is the longest stick that can be carried horizontally along a narrow corridor and around a right-angled bend?
  • Diagonals for Area
    problem

    Diagonals for Area

    Age
    16 to 18
    Challenge level
    2 out of 3
    Can you prove this formula for finding the area of a quadrilateral from its diagonals?
  • Screen Shot
    problem

    Screen Shot

    Age
    14 to 16
    Challenge level
    2 out of 3
    A moveable screen slides along a mirrored corridor towards a centrally placed light source. A ray of light from that source is directed towards a wall of the corridor, which it strikes at 45 degrees before being reflected across to the opposite wall and so on until it hits the screen.
  • Sine and Cosine for Connected Angles
    problem

    Sine and Cosine for Connected Angles

    Age
    14 to 16
    Challenge level
    2 out of 3
    The length AM can be calculated using trigonometry in two different ways. Create this pair of equivalent calculations for different peg boards, notice a general result, and account for it.
  • Flight Path
    problem

    Flight Path

    Age
    16 to 18
    Challenge level
    2 out of 3
    Use simple trigonometry to calculate the distance along the flight path from London to Sydney.
  • Raising The Roof
    problem

    Raising the Roof

    Age
    14 to 16
    Challenge level
    2 out of 3
    How far should the roof overhang to shade windows from the mid-day sun?
  • Pumping the Power
    problem

    Pumping the Power

    Age
    16 to 18
    Challenge level
    2 out of 3
    What is an AC voltage? How much power does an AC power source supply?
  • At a glance
    problem

    At a Glance

    Age
    14 to 16
    Challenge level
    3 out of 3
    The area of a regular pentagon looks about twice as a big as the pentangle star drawn within it. Is it?
  • Circumnavigation
    problem

    Circumnavigation

    Age
    14 to 16
    Challenge level
    3 out of 3
    The sides of a triangle are 25, 39 and 40 units of length. Find the diameter of the circumscribed circle.
  • Circle Scaling
    problem

    Circle Scaling

    Age
    14 to 16
    Challenge level
    3 out of 3
    Describe how to construct three circles which have areas in the ratio 1:2:3.