设等差数列{ an},{bn}前n项的各分别为Sn与Tn,若Sn/Tn=(2n)/(3n+1),则an/bn=?(要解题步骤)
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![设等差数列{ an},{bn}前n项的各分别为Sn与Tn,若Sn/Tn=(2n)/(3n+1),则an/bn=?(要解题步骤)](/uploads/image/z/9493752-48-2.jpg?t=%E8%AE%BE%E7%AD%89%E5%B7%AE%E6%95%B0%E5%88%97%7B+an%7D%2C%7Bbn%7D%E5%89%8Dn%E9%A1%B9%E7%9A%84%E5%90%84%E5%88%86%E5%88%AB%E4%B8%BASn%E4%B8%8ETn%2C%E8%8B%A5Sn%2FTn%3D%282n%29%2F%283n%2B1%29%2C%E5%88%99an%2Fbn%3D%3F%28%E8%A6%81%E8%A7%A3%E9%A2%98%E6%AD%A5%E9%AA%A4%29)
设等差数列{ an},{bn}前n项的各分别为Sn与Tn,若Sn/Tn=(2n)/(3n+1),则an/bn=?(要解题步骤)
设等差数列{ an},{bn}前n项的各分别为Sn与Tn,若Sn/Tn=(2n)/(3n+1),则an/bn=?(要解题步骤)
设等差数列{ an},{bn}前n项的各分别为Sn与Tn,若Sn/Tn=(2n)/(3n+1),则an/bn=?(要解题步骤)
附图是详细解答
Sn/Tn=2n/(3n+1),即
S(2n-1)/T(2n-1)=2(2n-1)/[3(2n-1)+1]=(2n-1)/(3n-1),即
[a1+a(2n-1)]/[b1+b(2n-1)]=(2n-1)/(3n-1),即
2an/2bn=(2n-1)/(3n-1),
an/bn=(2n-1)/(3n-1)