震离刻印怎么配-专注有问必答的平台

震离刻印怎么配-专注有问必答的平台

(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.

若以单集1.5分钟、需付费2元的标准来计算，追完这部总时长2.7小时的短剧需要支付约198元。，”李村党支部书记李夫峰说。

电机和减速机牙箱比怎么算？

电机和减速机牙箱比通常是通过计算两者的输出转速比得出的。转速比是指输出轴转速与输入轴转速之间的比值。 假设电机的输出转速为N1（单位：转/分钟），减速机的输出转速为N2（单位：转/分钟），则转速比R可以通过下式来计算： R = N2 / N1 牙箱比通常是指减速机输入轴和输出轴的齿轮的齿数比。假设减速机输入轴的齿数为Z1，输出轴的齿数为Z2，则牙箱比可以通过下式计算： 牙箱比 = Z2 / Z1 一般情况下，电机和减速机的转速比和牙箱比之间存在一定的关联性。根据这个关联性，可以通过已知的转速比或者牙箱比来计算未知的值。

近日，2023年常规统计督察动员部署会在京召开。，紧接着，唐鹏本人也在争抢中抽筋，不得不下场休息。

35岁有个20岁的女儿，算不算常见？

在一般情况下，35岁有一个20岁的女儿并不常见。通常情况下，女性在20岁时才开始进入成人状态，这意味着当一个女性35岁时，她的子女通常还没有达到成年。然而，在某些特定情况下，例如家庭早婚或者再婚，也有可能会发生这种情况。因此，虽然不常见，但也不是完全不可能。

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