(1/2+1/3···+1/2003)(1+1/2+1/3+···+1/2004)-(1+1/2+1/3+···+1/2
1+2++3+··········+10000=
1!+2!+3!·····n! 公式
1、2·······
有理数加减运算(-1)+(+2)+(-3)+(+4)+·····(-2001)+(2002)+(2003)+(2004)
计算 1*2/1+2*3/1+3*4/1+············+2009*2010/1
俗语和名句的填空1······,自知之明.2······,行必果.3工欲善其事,······.4临渊羡鱼,······.
数列 1/2,3/2,1/3 ,4/3,·········1/n+1,n+2/n+1,·········是否有极限?
1/3+2/3=1,但0.333···+0.666···=0.999···,为神马?额······谁能解释一下·····
1、2、3···2004、2005、2006按
1+2+3+4·······+98+99等于多少
1*2*3···2008*2009*(-1)*(-1/2)*(-1/3)···(-1/2008)*(1/2009)
1/2x-1/3y=1 -1/3x-y=2/3 解方程,急··········