1x2=1/3x[1x2x3-0x1x2] 2x3=1/3x[2x3x4-1x2x3] 3x4=1/3x[3x4x5-2x3x4]yo由以上三个等式相加,可得,计算3题1x2=1/3x[1x2x3-0x1x2] 2x3=1/3x[2x3x4-1x2x3] 3x4=1/3x[3x4x5-2x3x4]yo由以上三个等式相加,可得1x2+2x3+3x4=1/3x3x4x5=20读完以上
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/27 12:49:18
![1x2=1/3x[1x2x3-0x1x2] 2x3=1/3x[2x3x4-1x2x3] 3x4=1/3x[3x4x5-2x3x4]yo由以上三个等式相加,可得,计算3题1x2=1/3x[1x2x3-0x1x2] 2x3=1/3x[2x3x4-1x2x3] 3x4=1/3x[3x4x5-2x3x4]yo由以上三个等式相加,可得1x2+2x3+3x4=1/3x3x4x5=20读完以上](/uploads/image/z/2593850-50-0.jpg?t=1x2%3D1%2F3x%5B1x2x3-0x1x2%5D+2x3%3D1%2F3x%5B2x3x4-1x2x3%5D+3x4%3D1%2F3x%5B3x4x5-2x3x4%5Dyo%E7%94%B1%E4%BB%A5%E4%B8%8A%E4%B8%89%E4%B8%AA%E7%AD%89%E5%BC%8F%E7%9B%B8%E5%8A%A0%2C%E5%8F%AF%E5%BE%97%2C%E8%AE%A1%E7%AE%973%E9%A2%981x2%3D1%2F3x%5B1x2x3-0x1x2%5D+2x3%3D1%2F3x%5B2x3x4-1x2x3%5D+3x4%3D1%2F3x%5B3x4x5-2x3x4%5Dyo%E7%94%B1%E4%BB%A5%E4%B8%8A%E4%B8%89%E4%B8%AA%E7%AD%89%E5%BC%8F%E7%9B%B8%E5%8A%A0%2C%E5%8F%AF%E5%BE%971x2%2B2x3%2B3x4%3D1%2F3x3x4x5%3D20%E8%AF%BB%E5%AE%8C%E4%BB%A5%E4%B8%8A)
1x2=1/3x[1x2x3-0x1x2] 2x3=1/3x[2x3x4-1x2x3] 3x4=1/3x[3x4x5-2x3x4]yo由以上三个等式相加,可得,计算3题1x2=1/3x[1x2x3-0x1x2] 2x3=1/3x[2x3x4-1x2x3] 3x4=1/3x[3x4x5-2x3x4]yo由以上三个等式相加,可得1x2+2x3+3x4=1/3x3x4x5=20读完以上
1x2=1/3x[1x2x3-0x1x2] 2x3=1/3x[2x3x4-1x2x3] 3x4=1/3x[3x4x5-2x3x4]yo由以上三个等式相加,可得,计算3题
1x2=1/3x[1x2x3-0x1x2] 2x3=1/3x[2x3x4-1x2x3] 3x4=1/3x[3x4x5-2x3x4]yo由以上三个等式相加,可得
1x2+2x3+3x4=1/3x3x4x5=20
读完以上材料,请你计算下列各题【写出过程】
【1】1x2+2x3+3x4+...+10x11
【2】1x2+2x3+3x4+...+nx[n+1]
【3】请类比以上形式,尝试连续三个字然数的乘积的规律并计算
1x2x3+2x3x4+3x4x5+...+7x8x9
1x2=1/3x[1x2x3-0x1x2] 2x3=1/3x[2x3x4-1x2x3] 3x4=1/3x[3x4x5-2x3x4]yo由以上三个等式相加,可得,计算3题1x2=1/3x[1x2x3-0x1x2] 2x3=1/3x[2x3x4-1x2x3] 3x4=1/3x[3x4x5-2x3x4]yo由以上三个等式相加,可得1x2+2x3+3x4=1/3x3x4x5=20读完以上
【1】1x2+2x3+3x4+...+10x11
=10×11×12/3
=440
【2】1x2+2x3+3x4+...+nx[n+1]
=n(n+1)(n+2)/3
【3】请类比以上形式,尝试连续三个字然数的乘积的规律并计算
1x2x3+2x3x4+3x4x5+...+7x8x9
=7×8×9×10/4
=1260