求数列的前n项和是高考中的常见题型,每年都会涉及到,掌握数列的前n项和求和的常见方法是解好这一类题的关键,求数列的前n项和必须借助于通项公式,再在分析通项公式的基础上,或分解为数列求和,或转化为数列求和,下面就数列的前n项和常见方法谈谈。 The first n items in the series and the common questions in the college entrance examination are involved every year. The common way to master the first n items and the summation of the series is to solve the key problem of this type of problem. The first n items and the necessary number must be solved. With the aid of the general term formula, and then on the basis of the analysis of the general term formula, or decomposed into a series of sums, or converted into a series of sums, the following discussion of the top n terms of the series and common methods.