An=n*a1+n(n-1)*d1/2
Bn=n*b1+n(n-1)*d2/2
An/Bn
=[2a1+(n-1)*d1]/[2a1+(n-1)*d1]
=(5n+3)/(2n-1)
a1=4
b1=0.5
d1=5
d2=2
an/bn
=[4+5(n-1)]/[0.5+2(n-1)]
=(5n-4)/(2n-0.5)
{an}{bn}都是等差数列,已知An/Bn(各自前n项和)=(5n+3)/(2n-1)
{an}{bn}都是等差数列,已知An/Bn(各自前n项和)=(5n+3)/(2n-1)
则an/bn=?
则an/bn=?
数学人气:169 ℃时间:2020-04-30 22:53:11
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