100的平方减99的平方加98的平方减97的平方加96的平方减95的平方+.加2的平方减1的平方
人气:340 ℃ 时间:2020-02-23 01:53:42
解答
用平方差
100*100-99*99+98*98-97*97+96*96-95*95+.+4*4-3*3+2*2-1*1
=(100-99)(100+99)+(98-97)(98+97)+……(2-1)(2+1)
=100+99+98+97+……+2+1
=(100+1)+(99+2)+……(51+50)
=101*50=5050
推荐
猜你喜欢
- The farmer soon came back to get his shoes,but when he put his foot into one of his shoes and felt something hard,he fou
- 求y=lnx在点M(e,1)的切线方程和法线方程.
- It feel like three
- 骨骼不含钙有没有无机盐
- 硫酸铵和硫酸铁铵的ph值大小
- A.refresh B.renew C.stimulate D.encourage
- 如图所示,在△ABC中,AB=AC,点MN分别在BC所在的直线上,且AM=AN,BM与CN相等吗?两种解答方法.
- 巳知电压为380v功率45千瓦,用多大的空气开关,线的大少,是怎么算的!请高手多指教谢谢了.