1/1X3+1/3X5+1/5x7+1/7+9+…+1/49x51=?
1+2x3+4x5+6x7+.50x51的和是奇数还是偶数?写出原因
1/1x3+1/3x5+1/5x7+1/7x9+1/9x11=?
2/1x3+2/3X5+2/5x7=2/7x9+2/9x11
1/1x3+1/3x5+1/5x7+……+1/99x101
1/1x3+1/3x5+1/5x7+…+1/2011x2013是多少?
1/1X3+1/3X5+1/5X7...1/17X19+1/19X21=
1/1x3+1/3x5+1/5x7+.+1/2009x2011=
1X3分之一+3X5分之一+5X7分之一…+2011X2013分之一
已知1-1/3=2/1x3,计算1/1x3+1/3x5+1/5x7+1/7x9+1/9x11=
计算:1/1x3+1/3x5+1/5x7+1/7x9+……+1/2011x2013
x8+x7+x6+x5+x4+x3+x2+x+1因式分解
1/1x3+1/3x5+1/5x7.1/2009x2010+1/2011x2013