发现奇趣冷知识，尽在空气凤梨如何养！

发现奇趣冷知识，尽在空气凤梨如何养！

(1-1/2)+(1/2-1/3)+(1/3-1/4)+···+（1/2009-1/2010

To find the sum of the given series, we need to add all the terms together. (1 - 1/2) + (1/2 - 1/3) + (1/3 - 1/4) + ... + (1/2009 - 1/2010) We can simplify each term by finding the common denominator. 1 - 1/2 = 2/2 - 1/2 = 1/2 1/2 - 1/3 = 3/6 - 2/6 = 1/6 1/3 - 1/4 = 4/12 - 3/12 = 1/12 We can observe that each term follows this pattern - the denominator of the second fraction becomes the denominator of the first fraction in the next term. So, the series can be written as: 1/2 + 1/6 + 1/12 + ... + 1/2009 To find the sum of this series, we need to find the common denominator of all the fractions. The common denominator of 2, 6, 12, ..., 2009 will be the least common multiple (LCM) of these numbers. Calculating the LCM of these numbers is a bit lengthy. Instead, we can find the LCM of 2, 3, 4, ..., 2010, and then divide by the LCM of 2, 3, 4, ..., 2009. LCM(2, 3, 4, ..., 2010) / LCM(2, 3, 4, ..., 2009) = 2010 / 2 = 1005 So, the common denominator is 1005. To add the fractions, we need to express them with the common denominator: 1/2 = (1/2) * (1005/1005) = 1005/2010 1/6 = (1/6) * (1005/1005) = 167.5/2010 1/12 = (1/12) * (1005/1005) = 83.75/2010 Now we can add: 1005/2010 + 167.5/2010 + 83.75/2010 + ... + 1/2009 We can observe that the denominators of the fractions form an arithmetic sequence, and the numerators follow the same pattern. Using the formula for the sum of an arithmetic sequence: Sum = (first term + last term) * number of terms / 2 In this case, the first term is 1005/2010, the last term is 1/2009, and the number of terms is 2010. Sum = (1005/2010 + 1/2009) * 2010/2 Sum = (1005/2010 + 1/2009) * 1005 Sum = (1005 * 2009 + 1 * 2010) / 2 Sum = (2019955 + 2010) / 2 Sum = 2021965 / 2 Sum = 1010982.5 Therefore, the sum of the given series is 1010982.5.

，“培训主要围绕排污许可证执行报告填报规范、企业填报过程中的常见问题及相关的政策法规展开。

卫青死后，汉武帝诛杀了其整个家族，是在害怕什么？

据历史记载，在卫青去世后，汉武帝诛杀了他的整个家族，并收回了他们的封地和爵位。汉武帝之所以做出这一决定，是因为他害怕卫青家族过于强大可能对他的统治构成威胁。卫青和他的家族在汉朝有着崇高的声誉和影响力，他们在西汉初期的军事征战中立下了赫赫战功，拥有庞大的势力和财富。汉武帝担心卫青家族会借助他们的势力对他进行反抗或威胁汉朝的社会秩序和统一统治。因此，汉武帝决定铲除卫青家族，以减轻自己的压力和害怕。

近日，京口各街道（园区）组织开展第二轮集中行动，掀起人居环境整治新高潮。，实施用海审批“项目管家”服务，已保障用海58宗、面积1.84万亩，有效服务唐山曹妃甸新能源专用车零部件制造、黄骅港滚装码头一期等重点项目用海。

本兮到底死了没?

本文共有478人参与回答，点击这里发表你的个人建议吧！