1+(-2)+3+(-4)+.+2003+(-2004)| 1-1/2 | + | 1/2-1/3 | + | 1/3-1/4 | +.+ | 1/9-1/10 |

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/03 08:51:04
1+(-2)+3+(-4)+.+2003+(-2004)| 1-1/2 | + | 1/2-1/3 | + | 1/3-1/4 | +.+ | 1/9-1/10 |

1+(-2)+3+(-4)+.+2003+(-2004)| 1-1/2 | + | 1/2-1/3 | + | 1/3-1/4 | +.+ | 1/9-1/10 |
1+(-2)+3+(-4)+.+2003+(-2004)
| 1-1/2 | + | 1/2-1/3 | + | 1/3-1/4 | +.+ | 1/9-1/10 |

1+(-2)+3+(-4)+.+2003+(-2004)| 1-1/2 | + | 1/2-1/3 | + | 1/3-1/4 | +.+ | 1/9-1/10 |
1+(-2)+3+(-4)+.+2003+(-2004)
= (1 - 2) + (3 - 4) + ...+ (2003 - 2004)
= (-1)× 1002
= -1002
| 1-1/2 | + | 1/2-1/3 | + | 1/3-1/4 | +.+ | 1/9-1/10 |
= 1 - 1/2 + 1/2 - 1/3 + 1/3 - 1/4 + ...+ 1/9 - 1/10
= 1 - 1/10
= 9/10

-1002
9/10

1.1+(-2)+3+(-4)+......+2003+(-2004)
=[1+(-2)]+[3+(-4)]+......+[2003+(-2004)
=-1-1-......-1
=-2004/2
=-1002
2.| 1-1/2 | + | 1/2-1/3 | + | 1/3-1/4 | +......+ | 1/9-1/10 | =1-1/2 +1/2-1/3+1/3-1/4+......+1/9-1/10=1-1/10=9/10