学习几何,须手脑并用。三角尺是最常用的作图工具,其实,三角尺本身还可以用来拼图,帮助我们学习许多几何概念,深入研究一些几何问题呢。现在请你准备4只相同的含45°角的三角尺,我们一起动手玩拼图游戏(不计三角尺里层的“空心”部分,把每个三角尺看成图1中的“实心”直角三角形,也可按图2用正方形纸片折剪出4个直角三角形)。 Learning geometry, hands and brain and use. The triangle ruler is the most commonly used drawing tool. In fact, the triangle ruler itself can also be used for puzzles. It helps us to learn many geometric concepts and in-depth study of some geometric problems. Now, please prepare 4 identical triangle rulers with 45° angles. Let’s start jigsaw puzzles together (excluding the hollow part of the triangle ruler, and consider each triangle ruler as the “solid” right triangle in Figure 1). You can also cut out four right-angled triangles by using a square piece of paper as shown in Figure 2.