在组合知识的学习过程中,我们遇到了这样一道题:将1,2,3,…,14这14个数从小到大排列,再从这14个数中任意抽取3个数a1,a2,a3,且满足a2-a1≥3,a3-a2≥3.求满足条件的抽取方法有多少种?这道题背景新颖,与同学们经常处理的数字问题有很大区别,许多同学感到无从下手,使解题受到了挫? In the learning process of combinatorial knowledge, we encountered such a problem: arrange 14 numbers from 1, 2, 3, ..., 14 from small to large, and then randomly extract 3 numbers a1, a2 from these 14 numbers. A3, and meet the a2-a1 ≥ 3, a3-a2 ≥ 3. How many kinds of extraction methods to meet the conditions? This question background is novel, and the students often deal with the digital problem is very different, many students feel unable to start , so that the problem has been frustrated?