求03道数学题的运算过程

来源:百度知道 编辑:UC知道 时间:2024/06/03 17:25:06
我想知道下边这些题的运算过程
1.. 2001*20022002-2002*20012001
2. 2/3+2/15+2/35+2/63+2/99+2/143
3. 1994又1/1992*1992/1993

2001×2002×10001-2002×2001×10001=0
1-1/3+1/3-1/5+1/5-1/7+1/7-1/9+1/9-1/11+1/11-1/13=1-1/13=12/13
(1994×1992+1)/1993=((1993+1)(1993-1)+1)/1993
=(1993×1993-1+1)/1993=1993

2001*20022002-2002*20012001
=2001*20022002-2001*20012001+1*20012001
=2001*(20022002-20012001)+1*20012001
=2001*10001+20012001
=20012001+20012001
=20012001*2
=40024002

2001*20022002-2002*20012001
=2001*20022002-(2001+1)*20012001
=2001*1001-20012001
=0
2/3+2/15+2/35+2/63+2/99+2/143
=2/(1*3)+2/(3*5)+2/(5*7)+2/(7*9)+2/(9*11)+2/(11*13)
=1-1/3+1/3-1/5+1/5-1/7+1/7-1/9+1/9-1/11+1/11-1/13
=12/13
1994又1/1992*1992/1993
=1994*1992/1993我感觉这道题目不对!