A Wonderleaf question
What is trigonometry and how do sine and cosine work?
a real page from the book
Trigonometry is the math of triangle measurements, especially right triangles. Sine and cosine are ratios: sine compares the side opposite an angle with the longest side, while cosine compares the side beside that angle with the longest side.
The lovely trick is that triangles with the same angle keep matching proportions, even when one is huge and one is tiny. That lets people measure tall buildings, slopes, distances, and circles without climbing or stretching a tape measure across everything.
Wonder words
- angle
- ratio
- sine
- cosine
Try it out
Draw three right triangles with the same sharp angle, then compare how their side lengths grow together.
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