三角形内角余弦平方和的范围：3/4 ≤ cos²A+cos²B+cos²C ≤ 3
2017-10-13 06:42
本范例演示了三角形内角余弦平方和的不等式性质，即对于任意三角形ABC，其三个内角的余弦平方和满足 3/4 ≤ cos²A+cos²B+cos²C ≤ 3。通过GeoGebra的动态几何构造，直观展示了该不等式的成立条件及边界情况，帮助理解三角函数在三角形几何中的应用。
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