Sine, cosine, tangent

There are 60 NRICH Mathematical resources connected to Sine, cosine, tangent
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.
The Dodecahedron
problem

The dodecahedron

Age
16 to 18
Challenge level
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What are the shortest distances between the centres of opposite faces of a regular solid dodecahedron on the surface and through the middle of the dodecahedron?
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?
Six Discs
problem

Six discs

Age
14 to 16
Challenge level
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Six circular discs are packed in different-shaped boxes so that the discs touch their neighbours and the sides of the box. Can you put the boxes in order according to the areas of their bases?
Squ-areas
problem

Squ-areas

Age
14 to 16
Challenge level
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Three squares are drawn on the sides of a triangle ABC. Their areas are respectively 18 000, 20 000 and 26 000 square centimetres. If the outer vertices of the squares are joined, three more triangular areas are enclosed. What is the area of this convex hexagon?
Pythagoras on a Sphere
problem

Pythagoras on a sphere

Age
16 to 18
Challenge level
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Prove Pythagoras' Theorem for right-angled spherical triangles.
Strange Rectangle 2
problem

Strange rectangle 2

Age
16 to 18
Challenge level
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Find the exact values of some trig. ratios from this rectangle in which a cyclic quadrilateral cuts off four right angled triangles.
A Scale for the Solar System
problem

A scale for the solar system

Age
14 to 16
Challenge level
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The Earth is further from the Sun than Venus, but how much further? Twice as far? Ten times?
30-60-90 Polypuzzle
problem

30-60-90 polypuzzle

Age
16 to 18
Challenge level
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Re-arrange the pieces of the puzzle to form a rectangle and then to form an equilateral triangle. Calculate the angles and lengths.
Over The Pole
problem

Over the pole

Age
16 to 18
Challenge level
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Two places are diametrically opposite each other on the same line of latitude. Compare the distances between them travelling along the line of latitude and travelling over the nearest pole.