在学习圆锥体积的计算时,张老师引导学生根据圆柱的体积猜想等底等高的圆锥体积。此时,一个学生站起来说:“我们知道,一个长方形以它的一条边AB为轴旋转一周就得到一个圆柱。如果将这个长方形沿对角线剪开,再将得到的三角形以AB这条边为轴旋转一周,就得到一个圆锥。因为这个三角形的面积等于这个长方形 When learning the calculation of the cone volume, Zhang instructed the student to guess the contour cone volume at the end of the cylinder according to the volume of the cylinder. At this point, a student stands up and says: ”We know that a rectangle gets a cylinder by rotating it for a week with one of its sides AB. If you cut this rectangle diagonally and then get the triangle AB The edge of the side of the shaft for a week, you get a cone. Because the area of ​​the triangle is equal to the rectangle