已知2#3=2X3X4,4#2=4X5请计算(6#3)-(5#2)等于多少
求规律 根号1x(乘法的意思)2x3x4+1=5 根号2x3x4x5+1=11 根号3x4x5x6+1=19 根号4x5
1x5+2x5+3x5+4x5+5x5… 麻烦给我一个公式.
请1/1x2x3+1/2x3x4+1/3x4x5+1/4x5x6=
1/1x2x3+1/2x3x4+1/3x4x5+1/4x5x6+...+1/8x9x10 等于多少?
已知x=(根号5-1)/2,则x+x2+x3+x4+x5的值等于多少
如果定义(3)=2x3x4,(5)=4x5x6,(9)=8x9x10,那么(4)+(6)是多少?
1x2x3=6 3x4x5=60 5x6x7=210 2x3x4=24 4x5x6=120三个连续自然数(0除外)的乘积
1x2X3+2x3X4+3x4X5+…+7X8X9=?
1x2x3+2x3x4+3x4x5+...+7x8x9=,
1x2x3+2x3x4+3x4x5+4x5x6+...+n(n+1)(n+2)=
1/2x3x4+1/3x4x5+1/4x5x6+……+1/48x49x50=
1/1x2x3+1/2x3x4+1/3x4x5+1/4x5x6+.+1/48x49x50=