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The third of three articles on the History of Trigonometry.
The second of three articles on the History of Trigonometry.
The first of three articles on the History of Trigonometry. This takes us from the Egyptians to early work on trigonometry in China.
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.
Logo helps us to understand gradients of lines and why Muggles Magic is not magic but mathematics. See the problem Muggles magic.
Follow the instructions and you can take a rectangle, cut it into 4 pieces, discard two small triangles, put together the remaining two pieces and end up with a rectangle the same size. Try it!