如果定义(3)=2x3x4,(5)=4x5x6,(9)=8x9x10,那么(4)+(6)是多少?
如果定义(3)=2x3x4,(5)=4x5x6,(9)=8x9x10,那么(4)+(6)是多少?
规定(3)=2X3X4,(4)=3X4X5,(5)=4X5X6,.如果1/(6)+1/(7)=1/(7)X·,那么· 等
1x2x3=6 3x4x5=60 5x6x7=210 2x3x4=24 4x5x6=120三个连续自然数(0除外)的乘积
1/1x2x3+1/2x3x4+1/3x4x5+1/4x5x6+...+1/8x9x10 等于多少?
1/2x3X4十1/3X4x5十1/4X5X6……十1/8X9X10等于多少最好给个详细答案谢谢
1x2x3+2x3x4+3x4x5+4x5x6+...+n(n+1)(n+2)=
1/2x3x4+1/3x4x5+1/4x5x6+……+1/48x49x50=
请1/1x2x3+1/2x3x4+1/3x4x5+1/4x5x6=
1/1x2x3+1/2x3x4+1/3x4x5+1/4x5x6+.+1/48x49x50=
1/1x2x3+1/2x3x4+1/3x4x5+1/4x5x6+1/5x6x7=?这类题
1x2x3+2x3x4+3x4x5+…+8x9x10
根号[(1x2x3+2x4x6+...+nx2nx3n)/(1x3x4+2x6x8+...+nx3nx4n))=?