已经数列An中 a1等于1 An+1=2An\An+2 求该数列的通项公式An

题目是这样吧a1=1,a(n+1)=2*an/((an)+2)由题易知,an>0两边倒数,得1/a(n+1)=(an+2)/(2*an)得1/a(n+1)=an/(2*an)+2/(2*an)即1/a(n+1)=1/2+1/an即数列{1/an}为首项1/2+1/1=3/2,公差为1/2的等差数列故1/an=3/2+(n-1)*(1/...