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定理:相似三角形面积的比等于它们相似比的平方。《初中试用课本》几何《一册204页》从表面上看,这个定理的两个相似三角形面积的比,比值不易确定;它们的相似比又是平方,这和常见的含一次线段比的题目不相适直。因而,一般人认为这个定理不易应用;即使对少数习题能够应用,但是,用起来也可能很麻烦。所以,只有当题目中直接涉及到面积的比或线段平方的比时,才能用这个定理试一试;如果题目中不含面积的比或线段平方的比,就根本想不到这个定理的应用。尽管课本上有一些重要定理和习题都可应用这个定理进行证明,但是,在《教学参考书》的习题提示及答案里很少见到它的应用。同时,在一些数
Theorem: The ratio of similar triangle areas equals the square of their similarity ratio. “Junior Trial Textbook Geometry” “a volume of 204 pages” From the surface point of view, the ratio of the ratio of the two similar triangles of the theorem, the ratio is not easy to determine; their similarity is square, this and the common problem with a single line segment Not right. Therefore, most people think that this theorem is not easy to apply; even if it is applied to a small number of exercises, it may be very troublesome to use. Therefore, only when the subject directly relates to the ratio of the area or the square of the line segment, can use this theorem to try; if the title does not contain the ratio of the area or the ratio of the square of the line, the application of the theorem is not expected at all. Although there are some important theorems and exercises in the textbook, this theorem can be used to prove it. However, it is rarely seen in the “Teaching Reference” exercise hints and answers. At the same time, in some numbers