已知數(shù)列的前n項(xiàng)和=3n-2.求的通項(xiàng)公式. 查看更多

 

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已知數(shù)列{an}前n項(xiàng)和Sn=2n2-3n,數(shù)列{bn}是各項(xiàng)為正的等比數(shù)列,滿足a1=-b1,b3(a2-a1)=b1
(1)求數(shù)列{an},{bn}的通項(xiàng)公式;
(2)記cn=an•bn,求cn的最大值.

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已知數(shù)列{an}前n項(xiàng)和為Sn,求下列條件下數(shù)列的通項(xiàng)公式an
(1)Sn=2•5n-2;
(2)a1=2,an+1=an+3n+2;
(3)a1=1,an=
n-1n
an-1(n≥2)
;    
(4)a1=1,an+1=3an+2.

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已知數(shù)列{an}前n項(xiàng)和為Sn,求下列條件下數(shù)列的通項(xiàng)公式an
(1)數(shù)學(xué)公式;
(2)a1=2,an+1=an+3n+2;
(3)a1=1,數(shù)學(xué)公式;  
(4)a1=1,an+1=3an+2.

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已知數(shù)列{an}前n項(xiàng)和為Sn,求下列條件下數(shù)列的通項(xiàng)公式an
(1);
(2)a1=2,an+1=an+3n+2;
(3)a1=1,;    
(4)a1=1,an+1=3an+2.

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已知數(shù)列{an}前n項(xiàng)和Sn=2n2-3n,數(shù)列{bn}是各項(xiàng)為正的等比數(shù)列,滿足a1=-b1,b3(a2-a1)=b1
(1)求數(shù)列{an},{bn}的通項(xiàng)公式;
(2)記cn=an•bn,求cn的最大值.

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