作为微积分基础的极限是初等数学和高等数学的衔接点,有些极限求值题看上去很难,其实经过深入思考,不但能够解决,而且可以找到多种方法.下面是课本中的一道习题,我共找到了四种解法,各有妙处.在探索过程中.我得到了很多收获,锻炼了思维品质.希望读者也能受益. The limit of calculus is based on the convergence of elementary mathematics and advanced mathematics. Some limited-evaluation questions seem to be difficult. In fact, after thorough thinking, not only can they be solved, but also a variety of methods can be found. The following is an exercise in the textbook. I found a total of four solutions, each with its own virtues. During the exploration process, I got a lot of gains and exercised the quality of thinking. I hope the readers can also benefit.