求等比,差数列已知a,b,c成等比数列,a,x,b和b,y,c都成等差数列,且xy≠0,则a÷x+b÷y▇▇▇▇.▇▇▇▇.▇▇▇▇▇▇▇▇◢▇▇▇▇◣◢▇▇▇▇◣◢▇▇▇▇◣◢▇▇▇▇◣▇元旦快乐▇.

Question

求等比,差数列
已知a,b,c成等比数列,a,x,b和b,y,c都成等差数列,且xy≠0,则a÷x+b÷y
▇▇▇▇ .▇▇▇▇ .▇▇▇▇ ▇▇▇▇
◢▇▇▇▇◣ ◢▇▇▇▇◣ ◢▇▇▇▇◣ ◢▇▇▇▇◣
▇元旦快乐▇.▇生活愉快▇ ▇吉祥如意▇ ▇合家欢乐▇
◥▇▇▇▇◤ .◥▇▇▇▇◤ ◥▇▇▇▇◤ ◥▇▇▇▇◤
▇▇▇▇ .▇▇▇▇ .▇▇▇▇ ▇▇▇▇
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Answer 1

由已知得2x=a+b,2y=b+c设a/x+c/y=a/[(a+b)/2]+c/[(b+c)/2]=2a/(a+b)+2c/(b+c)由a,b,c成等比数列设a,b,c分别为a,aq,aqq带入得,a/x+c/y=2a/(a+aq)+2aqq/(aq+aqq)=2a/(a+aq)+2aq/(a+aq)=(2a+2aq)/(a+aq)=2...