高一数学课堂练习,我给出了一道2000年高考题:设｛an｝是首项为1的正项数列,且(n+1)a2-na2+an+1an=0,则它的通项公式是an=。该题只涉及数列通项公式的基本概念,根据题目特点,所用方法主要是归纳与猜想,当然也可直接用递推的方法求解,题意也很明确。但想不到的是,在A班上课时加 In mathematics class exercises, I gave a 2000 college entrance examination question: Let {an} be a positive term number 1 for the first item, and (n+1)a2-na2+an+1an=0, then it’s The item formula is an=. This question only involves the basic concept of series general term formula. According to the characteristics of the topic, the method used is mainly induction and conjecture. Of course, it can also be directly solved by recursive method. The meaning of the question is also very clear. But unexpectedly, when class A was added