学习了勾股定理后,我们容易推出如下两种特殊直角三角形的三边之比:1.在有一个锐角为30°的直角三角形中,30°的锐角所对的直角边、邻边、斜边之比为1:3~(1/2):2;2.在有一个锐角为45°的直角三角形中,45°的锐角所对的直角边、邻边、斜边之比为1:1:2~(1/2).解答含特殊角30°,或45°,或60°的图形问题时,要注意直接应用或创造条件应用它们所属的特殊直角 After studying the Pythagorean theorem, we can easily deduce the ratio of the three sides of the following two special right-angled triangles: 1. In a right-angled triangle with an acute angle of 30 °, the right-angled side, the adjacent side, the oblique Edge ratio of 1: 3 ~ (1/2): 2; 2. In a right-angled triangle with a 45 ° angle, the 45 ° acute angle to the right-angle side, 1: 2 ~ (1/2) .When answering a graphics problem with a particular angle of 30 °, or 45 °, or 60 °, care should be taken to apply directly or create the conditions that apply to the particular right angle they belong to