已知数列{an}的前m项(m为大于1的常数)满足a1/(a1+1)=a2/(a2+3)=a3/(a3+5)=...=am/(am+2m-1),且a1+a2+...+am=8,求a1

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已知数列{an}的前m项(m为大于1的常数)满足a1/(a1+1)=a2/(a2+3)=a3/(a3+5)=...=am/(am+2m-1),且a1+a2+...+am=8,求a1

已知数列{an}的前m项(m为大于1的常数)满足a1/(a1+1)=a2/(a2+3)=a3/(a3+5)=...=am/(am+2m-1),且a1+a2+...+am=8,求a1
已知数列{an}的前m项(m为大于1的常数)满足a1/(a1+1)=a2/(a2+3)=a3/(a3+5)=...=am/(am+2m-1),且a1+a2+...+am=8,求a1

已知数列{an}的前m项(m为大于1的常数)满足a1/(a1+1)=a2/(a2+3)=a3/(a3+5)=...=am/(am+2m-1),且a1+a2+...+am=8,求a1
首先数列{an}各项都不等于零,这个自己简单推一下.
a1/(a1+1)=a2/(a2+3)=a3/(a3+5)=...=am/(am+2m-1)
取倒数,有:
1/a1=3/a2=5/a3=...=(2m-1)/am
即a1=a2/3=a3/5=...=am/(2m-1)
a1+a2+...+am=a1+3*a1+5*a1+...+(2m-1)*a1=m^2*a1=8
a1=8/m^2