整体思想在代数学习中经常用到,在解决几何问题时,我们往往习惯于将问题“化整为零”,先解决各个小问题后再“积零为整”;但是,有时候则需要我们“反其道而行之”,即从整体人手全面考虑. 一、求线段的长度例1 (1999年安徽省)如图1,在高2米,坡角30°的楼梯表面铺地毯,地毯的长度至少需要_____米. The overall idea is often used in algebra learning. When solving geometric problems, we are often accustomed to “segmenting” the problem to the first solution to each minor problem and then “zeroing to zero”; however, sometimes we need us. “Reversing the line”, that is to say, considering the overall manpower. First, seeking the length of the line segment Example 1 (Anhui, 1999) As shown in Figure 1, the surface of a staircase with a height of 2 meters and a slope angle of 30 degrees is covered with carpets. The length needs at least _____ meters.