Sine, cosine, tangent

There are 60 NRICH Mathematical resources connected to Sine, cosine, tangent
Sine Problem
problem

Sine problem

Age
16 to 18
Challenge level
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In this 'mesh' of sine graphs, one of the graphs is the graph of the sine function. Find the equations of the other graphs to reproduce the pattern.
Circle Box
problem

Circle box

Age
14 to 16
Challenge level
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It is obvious that we can fit four circles of diameter 1 unit in a square of side 2 without overlapping. What is the smallest square into which we can fit 3 circles of diameter 1 unit?
Eight Ratios
problem

Eight ratios

Age
14 to 16
Challenge level
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Two perpendicular lines lie across each other and the end points are joined to form a quadrilateral. Eight ratios are defined, three are given but five need to be found.
Making Maths: Clinometer
page

Making maths: clinometer

You can use a clinometer to measure the height of tall things that you can't possibly reach to the top of, Make a clinometer and use it to help you estimate the heights of tall objects.
Why stop at Three by One
article

Why stop at three by one

Beautiful mathematics. Two 18 year old students gave eight different proofs of one result then generalised it from the 3 by 1 case to the n by 1 case and proved the general result.
Muggles, Logo and Gradients
article

Muggles, logo and gradients

Logo helps us to understand gradients of lines and why Muggles Magic is not magic but mathematics. See the problem Muggles magic.
The History of Trigonometry- Part 1
article

The history of trigonometry- part 1

The first of three articles on the History of Trigonometry. This takes us from the Egyptians to early work on trigonometry in China.