Trigonometric Inequality Visualization: -3 ≤ cosA+cosB+cosC ≤ 3/2

2017-10-14 06:43
This GeoGebra applet interactively demonstrates the trigonometric inequality -3 ≤ cosA + cosB + cosC ≤ 3/2. Users can adjust angles A, B, and C via draggable points and parameters to observe real-time changes in the cosine sum, verifying the upper and lower bounds. The visualization incorporates vectors, contour lines, and extremum annotations, intuitively illustrating that the maximum value of 3/