速速速速速速速速速速速速速速速速速速速速速速!(1+1/2+1/3+1/4)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘(1/2+1/3+1/4)这个是简算,怎么能用计算机!
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/14 06:43:43
![速速速速速速速速速速速速速速速速速速速速速速!(1+1/2+1/3+1/4)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘(1/2+1/3+1/4)这个是简算,怎么能用计算机!](/uploads/image/z/965002-58-2.jpg?t=%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%21%EF%BC%881%2B1%2F2%2B1%2F3%2B1%2F4%EF%BC%89%E4%B9%98%EF%BC%881%2F2%2B1%2F3%2B1%2F4%2B1%2F5%EF%BC%89%EF%BC%8D%EF%BC%881%2B1%2F2%2B1%2F3%2B1%2F4%2B1%2F5%EF%BC%89%E4%B9%98%EF%BC%881%2F2%2B1%2F3%2B1%2F4%EF%BC%89%E8%BF%99%E4%B8%AA%E6%98%AF%E7%AE%80%E7%AE%97%EF%BC%8C%E6%80%8E%E4%B9%88%E8%83%BD%E7%94%A8%E8%AE%A1%E7%AE%97%E6%9C%BA%EF%BC%81)
速速速速速速速速速速速速速速速速速速速速速速!(1+1/2+1/3+1/4)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘(1/2+1/3+1/4)这个是简算,怎么能用计算机!
速速速速速速速速速速速速速速速速速速速速速速!
(1+1/2+1/3+1/4)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘(1/2+1/3+1/4)
这个是简算,怎么能用计算机!
速速速速速速速速速速速速速速速速速速速速速速!(1+1/2+1/3+1/4)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘(1/2+1/3+1/4)这个是简算,怎么能用计算机!
这个我前几天学清华少儿数学时学过.
(1+1/2+1/3+1/4)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘(1/2+1/3+1/4)
=A乘 (1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘B
=(B+1)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘B
=B乘(1/2+1/3+1/4+1/5)+1乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘B
=B乘(1/2+1/3+1/4+1/5)+1乘(1/2+1/3+1/4+1/5)-(1/2+1/3+1/4+1/5)乘B+B
=(1/2+1/3+1/4+1/5)-(1/2+1/3+1/4)
=1/5
令a=1/2+1/3+1/4
则1+1/2+1/3+1/4=1+a
1/2+1/3+1/4+1/5=a+1/5
1+1/2+1/3+1/4+1/5=1+a+1/5
所以原式=(1+a)(a+1/5)-(1+a+1/5)a
=a(1+a)+1/5(1+a)-a(1+a)-1/5a
=1/5(1+a)-1/5a
=1/5+1/5a-1/5a
=1/5
(1/2+1/3+1/4+1/5)+(1/2+1/3+1/4)X(1/2+1/3+1/4+1/5)-[1/2+1/3+1/4+(1/2+1/3+1/4+1/5)X(1/2+1/3+1/4)]=1/5
(1+1/2+1/3+1/4)X(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)X(1/2+1/3+1/4)
=(1+1/2+1/3+1/4)X(1/2+1/3+1/4+1/5)-[(1+1/2+1/3+1/4)X(1/2+1/3+1/4)+1/5X(1/2+1/3+1/4)]
=(1+1/2+1/3+1/4)X(1/2+1/3+1/4+1/5)-(1+1...
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(1+1/2+1/3+1/4)X(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)X(1/2+1/3+1/4)
=(1+1/2+1/3+1/4)X(1/2+1/3+1/4+1/5)-[(1+1/2+1/3+1/4)X(1/2+1/3+1/4)+1/5X(1/2+1/3+1/4)]
=(1+1/2+1/3+1/4)X(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4)X(1/2+1/3+1/4)-1/5X(1/2+1/3+1/4)
=(1/2+1/3+1/4)X1/5-1/5X(1/2+1/3+1/4)
=1/5X1
=1/5
收起
=(1+1/2+1/3+1/4)乘(1/2+1/3+1/4)+1乘1/5+(1/2+1/3+1/4)乘1/5-(1+1/2+1/3+1/4)乘(1/2+1/3+1/4)-1/5乘(1/2+1/3+1/4)
1/2+1/3+1/4+1/5-1/2-1/3-1/4=1/5