Question

等差数列{an} {bn}前n项和为An Bn,An/Bn=(7n+2)/(4n+27),求an/bn

Answer 1

A(2n-1)=(a1+a(2n-1))/2*(2n-1)=2an/2*(2n-1)=an*(2n-1)

同理B(2n-1)=b*(2n-1)

于是an/bn=A(2n-1)/B(2n-1)=(14n-5)/(8n+23)