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Triangles and TrigonometryApplications

Reveal All Steps

But triangles and trigonometry are not just useful for measuring the height of mountains, and the tools and concepts you have learned are incredibly important in countless areas of mathematics, science and engineering.

Triangles are special because they are particularly strong. They are the only polygon that, when made out of wooden beams and hinges, will be completely rigid – unlike rectangles, for example, which you can easily push over.

COMING SOON – Animations

This property makes triangles particularly useful in construction, where they can carry heavy weights.

A “Truss bridge” is supported by triangular bars

Triangles in high-voltage electricity Pylons

Even bikes use triangles for stability.

Triangles are also the simplest polygon, with the fewest sides. This makes them particularly well suited to approximating complex curved surfaces. This is done in physical building…

“The Gherkin”, a skyscraper in London

Bank of China Tower in Hong Kong

Courtyard of the British Museum in London

…but also in virtual worlds. In computer generated graphics (e.g. for movies or video games), all surfaces are approximated using a “mesh” of tiny triangles. Artists and software engineers need to know about geometry and trigonometry in order to be able to move and transform these triangles realistically, and to calculate their colour and texture.

Many results from this course will be useful when studying bigger polygons like quadrilaterals or pentagons in the future.