Geometric Proof of the Double Angle Sine Formula
2020-04-10 02:06
This GeoGebra example provides a geometric proof of the double angle sine formula sin(2α) = 2sin(α)cos(α). Using constructions involving angles, rays, circles, perpendicular lines, and reflections, it visually demonstrates the trigonometric relationship between a double angle and its half angle. The dynamic illustration with intersecting points, segments, and angles helps learners understand the d
In collections
Secondary Vocational Mathematics
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S_{▵AOC}=2×S_{▵AOB}=2×\frac12\sinα·\cosα=\sinα·\cosα\\
∴\sin2α=2\sinα\cosα""/>
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