1.题目呈现题目(2014年全国新课标卷Ⅱ第17题)已知数列{a_n}满足a_1=1,a_(n+1)=3a_n+1.(1)证明{a_n+1/2}是等比数列,并求{a_n}的通项公式;(2)证明1/(a_1)+1/(a_2)+…+1/(a_n)≤3/2.点拨此题属于新课标全国卷Ⅱ中解答题的第一题,主要考查了判断数列为等比数列、求通项公式和一边为常数的数列不等式的证明.对于第(2)问,学生往往感 1. Topic Presentation (2014 National New Curriculum Vol. II Question 17) Known sequence {a_n} satisfies a_1=1,a_(n+1)=3a_n+1.(1)Prove that {a_n+1/2 } is a series of equal numbers, and find the general formula of {a_n}; (2) prove that 1/(a_1)+1/(a_2)+...+1/(a_n)≤3/2. The first question in the National Book II Problem Solving Question mainly examines the proof that the sequence of numbers is a series of equal numbers, a formula of a general term, and a series of inequalities of constants on one side. For the second question, students often feel