1的平方+2的平方+3的平方...+n的平方=n(n+1)(2n+1)/6那1+(1+2)+(1+2+3)+(1+2+3+4)+..(1+2+...+50)1+(1+2)+(1+2+3)+(1+2+3+4)+..(1+2+...+50)等于什么?必当加赏!
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/02 05:30:53
![1的平方+2的平方+3的平方...+n的平方=n(n+1)(2n+1)/6那1+(1+2)+(1+2+3)+(1+2+3+4)+..(1+2+...+50)1+(1+2)+(1+2+3)+(1+2+3+4)+..(1+2+...+50)等于什么?必当加赏!](/uploads/image/z/7617905-17-5.jpg?t=1%E7%9A%84%E5%B9%B3%E6%96%B9%2B2%E7%9A%84%E5%B9%B3%E6%96%B9%2B3%E7%9A%84%E5%B9%B3%E6%96%B9...%2Bn%E7%9A%84%E5%B9%B3%E6%96%B9%3Dn%EF%BC%88n%2B1%EF%BC%89%EF%BC%882n%2B1%EF%BC%89%2F6%E9%82%A31%2B%EF%BC%881%2B2%29%2B%281%2B2%2B3%29%2B%281%2B2%2B3%2B4%29%2B..%281%2B2%2B...%2B50%291%2B%EF%BC%881%2B2%29%2B%281%2B2%2B3%29%2B%281%2B2%2B3%2B4%29%2B..%281%2B2%2B...%2B50%29%E7%AD%89%E4%BA%8E%E4%BB%80%E4%B9%88%3F%E5%BF%85%E5%BD%93%E5%8A%A0%E8%B5%8F%21)
1的平方+2的平方+3的平方...+n的平方=n(n+1)(2n+1)/6那1+(1+2)+(1+2+3)+(1+2+3+4)+..(1+2+...+50)1+(1+2)+(1+2+3)+(1+2+3+4)+..(1+2+...+50)等于什么?必当加赏!
1的平方+2的平方+3的平方...+n的平方=n(n+1)(2n+1)/6那1+(1+2)+(1+2+3)+(1+2+3+4)+..(1+2+...+50)
1+(1+2)+(1+2+3)+(1+2+3+4)+..(1+2+...+50)等于什么?必当加赏!
1的平方+2的平方+3的平方...+n的平方=n(n+1)(2n+1)/6那1+(1+2)+(1+2+3)+(1+2+3+4)+..(1+2+...+50)1+(1+2)+(1+2+3)+(1+2+3+4)+..(1+2+...+50)等于什么?必当加赏!
1+(1+2)+(1+2+3)+...+(1+2+..+n)
=∑(i=1→n)i(i+1)/2
=(1/2)∑(i=1→n)i^2+(1/2)∑(i=1→n)i
=(1/2)n(n+1)(2n+1)/6+(1/2)n(n+1)/2
=n(n+1)(n+2)/6(毕).
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