数列求通项公式,是高考考查的重要内容之一,问题的关键在于对已知等式进行恰当的变形转化。数列给定条件通常是利用递推公式呈现,需要进行恒等变形,变形的方法常有:乘除法、分母消去法、添去项法、取对数倒数、待定系数、取乘方开方等方法。 The formula for calculating the sequence of numbers is one of the important contents of the college entrance examination. The crux of the problem lies in the proper transformation and transformation of known equations. The given conditions of sequence are usually presented by recursion formula. The methods of constant deformation and deformation are usually used: multiplication and division, denominator elimination method, addition term method, reciprocal of logarithm, undetermined coefficient, square of square method.