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锐角三角函数概念,建立在三角形相似的基础上,因此,相似三角形的研究,可以借助锐角三角函数,尤其当研究的几何图形中存在直角三角形时,利用锐角三角函数求解,会给你带来极大的方便,以下通过几例中考综合题的解法分析,谈谈这一方法的应用。 例1.如图,已知矩形ABCD,E是AB边上一点,AE∶EB=3∶5,沿CF折叠△BCE,使E点落在AD边上F点处,若CE=15(5(5~(1/2)),求四边形BCFE
The concept of the acute-angle trigonometric function is based on the similarity of triangles. Therefore, the study of similar triangles can be based on acute-angle trigonometric functions. Especially when there are right-angled triangles in the studied geometry, solving with an acute-angled trigonometric function will bring you a pole. Large convenience, the following through a few examples of comprehensive analysis of the test results, talk about the application of this method. Example 1. As shown in the figure, the known rectangle ABCD, E is a point on the AB side, AE:EB=3:5, folds △BCE along CF, so that the E point falls on the F point on the AD side, if CE=15 (5 (5~(1/2)), Quadrilateral BCFE