三角形内角余弦乘积的不等式：-1 ≤ cosA cosB cosC ≤ 1/8
2017-10-14 02:54
本GeoGebra范例演示了三角形三个内角余弦值乘积的取值范围，即 -1 ≤ cosA cosB cosC ≤ 1/8。通过动态调整三角形的形状，用户可以直观地观察余弦乘积的变化，并验证该经典三角不等式的上下界。当三角形为等边三角形时，乘积取得最大值 1/8；当三角形趋近于退化状态时，乘积趋近于最小值 -1。此范例结合了三角函数与最值优化，适合用于数学探究学习。
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