已知各项同号且均不为零的数列{An}的前n项和Sn满足Sn=(An-A n ²)/2,(1)求数列的通项公式{A n},(2)设数列{B n}满足B1=1,Bn+1 =Bn +2 ²,求数列An×(B n -2)求数列An×(B n -2)的前 n项和
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![已知各项同号且均不为零的数列{An}的前n项和Sn满足Sn=(An-A n ²)/2,(1)求数列的通项公式{A n},(2)设数列{B n}满足B1=1,Bn+1 =Bn +2 ²,求数列An×(B n -2)求数列An×(B n -2)的前 n项和](/uploads/image/z/14445388-28-8.jpg?t=%E5%B7%B2%E7%9F%A5%E5%90%84%E9%A1%B9%E5%90%8C%E5%8F%B7%E4%B8%94%E5%9D%87%E4%B8%8D%E4%B8%BA%E9%9B%B6%E7%9A%84%E6%95%B0%E5%88%97%7BAn%7D%E7%9A%84%E5%89%8Dn%E9%A1%B9%E5%92%8CSn%E6%BB%A1%E8%B6%B3Sn%3D%EF%BC%88An%EF%BC%8DA+n+%26%23178%3B%EF%BC%89%2F2%2C%281%29%E6%B1%82%E6%95%B0%E5%88%97%E7%9A%84%E9%80%9A%E9%A1%B9%E5%85%AC%E5%BC%8F%7BA+n%7D%2C%282%29%E8%AE%BE%E6%95%B0%E5%88%97%7BB+n%7D%E6%BB%A1%E8%B6%B3B1%3D1%2CBn%2B1+%3DBn+%EF%BC%8B2+%26%23178%3B%2C%E6%B1%82%E6%95%B0%E5%88%97An%C3%97%28B+n+%EF%BC%8D2%29%E6%B1%82%E6%95%B0%E5%88%97An%C3%97%28B+n++%EF%BC%8D2%29%E7%9A%84%E5%89%8D++n%E9%A1%B9%E5%92%8C)
已知各项同号且均不为零的数列{An}的前n项和Sn满足Sn=(An-A n ²)/2,(1)求数列的通项公式{A n},(2)设数列{B n}满足B1=1,Bn+1 =Bn +2 ²,求数列An×(B n -2)求数列An×(B n -2)的前 n项和
已知各项同号且均不为零的数列{An}的前n项和Sn满足Sn=(An-A n ²)/2,(1)求数列的通项公式{A n},(2)设数列{B n}满足B1=1,Bn+1 =Bn +2 ²,求数列An×(B n -2)
求数列An×(B n -2)的前 n项和
已知各项同号且均不为零的数列{An}的前n项和Sn满足Sn=(An-A n ²)/2,(1)求数列的通项公式{A n},(2)设数列{B n}满足B1=1,Bn+1 =Bn +2 ²,求数列An×(B n -2)求数列An×(B n -2)的前 n项和
1,Sn=(An-A n ²)/2,Sn-1=(An-1-A n-1 ²)/2,一式减二式得,An=(An-A n-1+A n-1 ²-A n ²)/2,2An=An-A n-1+(A n-1-A n )(A n-1 +A n),A n-1 +A n=(A n-1-A n )(A n-1 +A n),A n-1-A n=1,An-A n-1=-1,A1=S1=(A1-A 1²)/2,A1=-1,An=-1+(n-1)×(-1)=-n