Geometric Proof of the Sine Addition Formula (Improved)
2020-04-10 00:24
This GeoGebra applet provides an intuitive geometric proof of the sine addition formula, sin(α+β) = sinαcosβ + cosαsinβ. By constructing circles, segments, orthogonal lines, and angles, it builds a geometric model containing two angles and their sum. The trigonometric identity is derived through geometric relationships such as areas or segment lengths. The improved construction offers clearer logi
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Secondary Vocational Mathematics
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