Geometric Proof of the Double Angle Tangent Formula
2020-04-10 02:08
This GeoGebra example demonstrates a geometric proof of the double angle tangent formula tan(2α) = 2tan(α)/(1-tan²(α)). Using geometric constructions involving rays, circles, angles, orthogonal lines, and reflections, it builds a figure with multiple angles (α, β, γ, δ, etc.) to visually illustrate the derivation and geometric meaning of this trigonometric identity. The example transforms an algeb
In collections
Secondary Vocational Mathematics
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