论文部分内容阅读
问题等腰三角形一腰上的高与底边的夹角和顶角之间有何关系?并证明你的结论.(请读者自己先思考)猜想以上的问题是对任意等腰三角形而言的,所以,也适用于等边三角形,可用等边三角形进行探索.如图1,△ABC 是等边三角形,BD 是 AC 上的高,显然∠1=30°,∠A=60°,故∠1=(1/2)∠A.于是可猜想:等腰三角形一腰上的高与底边的夹角等于顶角的一半.
Question What is the relationship between the height of a waist and the angle between the included angle and the vertex angle of the bottom edge of the isosceles triangle? And prove your conclusion. (please ask the reader to think first) guess The above question is for any isosceles triangle. Therefore, it is also applicable to equilateral triangles, which can be explored using equilateral triangles. As shown in Figure 1, △ABC is an equilateral triangle, BD is high on AC, obviously ∠1=30°, ∠A=60°, so 1 = (1/2) ∠ A. Then you can guess: The angle between the height of the isosceles triangle and the bottom edge is equal to half the top angle.