Generalized Angle Substitution (180°, 360°)
2015-09-14 05:01
This applet demonstrates generalized angle substitution in the 180° to 360° range. By constructing vectors, midpoints, orthogonal lines, rotations, circles, and angles, it visually illustrates trigonometric sign changes across quadrants and angle transformations. Ideal for learning induction formulas and understanding the connection between angle rotation and coordinate geometry.
In collections
三角函數
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