已知数列an满足a1+2a2+2^2a3+...+2^n-1an=n/2(1).求数列an的通项公式.(2)设bn=(2n-1)an,求数列bn的...已知数列an满足a1+2a2+2^2a3+...+2^n-1an=n/2(1).求数列an的通项公式.(2)设bn=(2n-1)an,求数列bn的前n项和sn
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已知数列an满足a1+2a2+2^2a3+...+2^n-1an=n/2(1).求数列an的通项公式.(2)设bn=(2n-1)an,求数列bn的...已知数列an满足a1+2a2+2^2a3+...
已知数列an满足a1+2a2+2^2a3+...+2^n-1an=n/2(1).求数列an的通项公式.(2)设bn=(2n-1)an,求数列bn的...已知数列an满足a1+2a2+2^2a3+...+2^n-1an=n/2(1).求数列an的通项公式.(2)设bn=(2n-1)an,求数列bn的前n项和sn
已知数列an满足a1+2a2+2^2a3+...+2^n-1an=n/2(1).求数列an的通项公式.(2)设bn=(2n-1)an,求数列bn的...
已知数列an满足a1+2a2+2^2a3+...+2^n-1an=n/2(1).求数列an的通项公式.(2)设bn=(2n-1)an,求数列bn的前n项和sn
已知数列an满足a1+2a2+2^2a3+...+2^n-1an=n/2(1).求数列an的通项公式.(2)设bn=(2n-1)an,求数列bn的...已知数列an满足a1+2a2+2^2a3+...+2^n-1an=n/2(1).求数列an的通项公式.(2)设bn=(2n-1)an,求数列bn的前n项和sn
1)a1+2a2+...+2^n-1an=n/2(1)
a1+2a2+...+2^n-2a(n-1)=(n-1)/2(2)
(1)-(2):2^(n-1)an=1/2
an=1/2^n
2)Tn=1/2+…+(2n-1)/2^n
Tn/2=1/2^2+…+(2n-1)/2^(n+1)
两式相减乘2:
Tn=4-1/2(n-2)-1-(2n-1)/2^n
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