2*2+4*4+6*6+...+(2n)*(2n)
=4(1²+2²+3²+4²+…bai…+n²)
=4n(n+1)(2n+1)/6
=2n(n+1)(2n+1)/3
1*1+3*3+5*5+....+(2n-1)*(2n-1)
=1²+3²+5²+……+(2n-1)²
=[1²+2²+3²+4²+……+(2n)²]-[2*2+4*4+6*6+...+(2n)*(2n)]
=4n(2n+1)(4n+1)/3-2n(n+1)(2n+1)/3
=[2n(2n+1)/3][2(4n+1)-(n+1)]
=[2n(2n+1)/3][8n+2-n-1]
=[2n(2n+1)/3][7n+1]
=2n(2n+1)(7n+1)/3
扩展资料:
平方和相关公式:
(1)1+2+3+.+n=n(n+1)/2
(2)1^2+2^2+3^2+...+n^2=n(n+1)(2n+1)/6
(3)1×2+2×3+3×4+4×5+…+n(n+1)
=(1^2+1)+(2^2+2)+(3^2+2)+...+(n^2+n)
=(1^2+2^2+...+n^2)+(1+2+3+.+n)
=n(n+1)(2n+1)/6+n(n+1)/2
=n(n+1)(n+2)
连续奇数平方和的公式:1/6 (-1 + n) n (1 + n)
连续偶数平方和的公式:1/6 n (1 + n) (2 + n)
无论奇数或者偶数,公式均为:n(n+1)(n+2)/6其中n表示最后一项的数值
2*2+4*4+6*6+...+(2n)*(2n)
=4(1²+2²+3²+4²+……+n²)
=4n(n+1)(2n+1)/6
=2n(n+1)(2n+1)/3
1*1+3*3+5*5+....+(2n-1)*(2n-1)
=1²+3²+5²+……+(2n-1)²
=[1²+2²+3²+4²+……+(2n)²]-[2*2+4*4+6*6+...+(2n)*(2n)]
=4n(2n+1)(4n+1)/3-2n(n+1)(2n+1)/3
=[2n(2n+1)/3][2(4n+1)-(n+1)]
=[2n(2n+1)/3][8n+2-n-1]
=[2n(2n+1)/3][7n+1]
=2n(2n+1)(7n+1)/3
2*2+4*4+6*6+...+(2n)*(2n)=4(1^1+2^2+3^2+.....+n^2)