Sine, cosine, tangent

  • Where is the dot?
    problem

    Where is the dot?

    Age
    14 to 16
    Challenge level
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    A dot starts at the point (1,0) and turns anticlockwise. Can you estimate the height of the dot after it has turned through 45 degrees? Can you calculate its height?
  • Raising The Roof
    problem

    Raising the roof

    Age
    14 to 16
    Challenge level
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    How far should the roof overhang to shade windows from the mid-day sun?
  • Flight Path
    problem

    Flight path

    Age
    16 to 18
    Challenge level
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    Use simple trigonometry to calculate the distance along the flight path from London to Sydney.
  • Spokes
    problem

    Spokes

    Age
    16 to 18
    Challenge level
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    Draw three equal line segments in a unit circle to divide the circle into four parts of equal area.
  • Orbiting Billiard Balls
    problem

    Orbiting billiard balls

    Age
    14 to 16
    Challenge level
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    What angle is needed for a ball to do a circuit of the billiard table and then pass through its original position?
  • Sine and Cosine for Connected Angles
    problem

    Sine and cosine for connected angles

    Age
    14 to 16
    Challenge level
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    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.
  • Figure of Eight
    problem

    Figure of eight

    Age
    14 to 16
    Challenge level
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    On a nine-point pegboard a band is stretched over 4 pegs in a "figure of 8" arrangement. How many different "figure of 8" arrangements can be made ?
  • Screen Shot
    problem

    Screen shot

    Age
    14 to 16
    Challenge level
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    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.
  • Octa-flower
    problem

    Octa-flower

    Age
    16 to 18
    Challenge level
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    Join some regular octahedra, face touching face and one vertex of each meeting at a point. How many octahedra can you fit around this point?
  • Bend
    problem

    Bend

    Age
    16 to 18
    Challenge level
    filled star empty star empty star
    What is the longest stick that can be carried horizontally along a narrow corridor and around a right-angled bend?