图形对任意两个互相垂直的坐标轴的惯性矩之和等于它对两轴交点的极惯性矩。
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如果两个正交坐标轴之一为图形的对称轴,则这对坐标轴肯定是图形的主惯性轴。
A. 对
B. 错
平面图形对包含主轴的直角坐标系的惯性积一定等于零。
A. 对
B. 错
His visit is direct evidence of the (improve) in their relationship
I have always believed that a garden dies with its (create).
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