已知1△3=1X2X3,6△5=6X7X8X9X10,求2△5.
1x2X3+2x3X4+3x4X5+…+7X8X9=?
1x2x3+2x3x4+3x4x5+...+7x8x9=,
1x2x3=6 3x4x5=60 5x6x7=210 2x3x4=24 4x5x6=120三个连续自然数(0除外)的乘积
1x2=1/3(1x2x3=0x1x2 ) 2x3=1/3(2x3x4-1x2x3) 3x4=1/3(3x4x5- 2x
1x2=1|3(1x2x3-0x1x2) 2x3=1|3(2x3x4-1x2x3) 3x4=1|3(3x4x5-2x3x
观察下列各式:1X2=1/3(1x2x3-0x1x2) 2x3=1/3(2x3x4-1x2x3) 3x4=1/3(3x4
1x2=(1/3)(1x2x3-0x1x2) 3x4=(1/3)(3x4x5-2x3x4) 问1x2x3+2x3x4+.
一道找规律的题!观察下面三个特殊等式:1x2=1/3(1x2x3-0x1x2); 2x3=1/3(2x3x4-1x2x3
1x2=三分之一{1x2x3-0x1x2};2x3-三分之一{2x3x4-1x2x3}:3x4-三分之一{3x4x5-2
1/1x2x3+1/2x3x4+1/3x4x5+1/4x5x6+1/5x6x7=?这类题
1/1x2x3+1/2x3x4+1/3x4x5+1/4x5x6+.+1/48x49x50=
1/1x2x3+1/2x3x4+1/3x4x5+.+1/11x12x13=