1-3+5-7+9-11+13.+2001答案是多少_数学解答

1-3+5-7+9-11+13.+2001答案是多少

人气：393 ℃　时间：2020-03-23 07:47:56

解答

1 - 3 + 5 - 7 + 9 - 11 + 13 - 15 +... + 2001= (1 - 3) + (5 - 7) + (9 - 11) + (13 - 15) + ... + (1997 - 1999) + 2001= (-2) × 500 + 2001= -1000 + 2001= 1001