> 数学 >
计算:1/(1*3)+1/(3*5)+1/(5*7)+…+1/(49*51).
因为1/(1*2)=1-(1/2),1/(2*3)=(1/2)*(1/3),1/(3*4)=(1/3)-(1/4),……,1/(9*10)=(1/9)-(1/10).所以1/(1*2)+1/(2*3)+1/(3*4)+…+1/(9*10)=1-(1/2)+(1/2)-(1/3)+(1/3)-(1/4)+…+(1/9)-(1/10).
是计算:1/(1*3)+1/(3*5)+1/(5*7)+…+1/(49*51)。
人气:332 ℃ 时间:2019-12-10 02:02:11
解答
25/51因为1/(1*3)=(1/1-1/3)/2,1/(3*5)=(1/3-1/5)/2,1(5*7)=(1/5-1/7)/2...1(49*51)=(1/49-1/51)/2所以1/(1*3)+1/(3*5)+1/(5*7)+…+1/(49*51)=(1-1/3+1/3-1/5+1/5...+1/49-1/51)=(1-1/51)/2=25/51楼上2个...
推荐
猜你喜欢
© 2024 79432.Com All Rights Reserved.
电脑版|手机版