1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21 =[1*2*3*(1+2*2*2+7*7*7)/[1*3*5*(1+2*2*2+7*7*7)] =1*2*3/1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21 =[1*2*3*(1+2*2*2+7*7*7)/[1*3*5*(1+2*2*2+7*7*7)] =1*2*3/1*3*5 =2/5 为什么这么做?
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/07 03:12:24
![1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21 =[1*2*3*(1+2*2*2+7*7*7)/[1*3*5*(1+2*2*2+7*7*7)] =1*2*3/1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21 =[1*2*3*(1+2*2*2+7*7*7)/[1*3*5*(1+2*2*2+7*7*7)] =1*2*3/1*3*5 =2/5 为什么这么做?](/uploads/image/z/54888-24-8.jpg?t=1%2A3%2A5%2B2%2A6%2A10%2B7%2A21%2A35%E5%88%86%E4%B9%8B1%2A2%2A3%2B2%2A4%2A6%2B7%2A14%2A21+%3D%5B1%2A2%2A3%2A%281%2B2%2A2%2A2%2B7%2A7%2A7%29%2F%5B1%2A3%2A5%2A%281%2B2%2A2%2A2%2B7%2A7%2A7%29%5D+%3D1%2A2%2A3%2F1%2A3%2A5%2B2%2A6%2A10%2B7%2A21%2A35%E5%88%86%E4%B9%8B1%2A2%2A3%2B2%2A4%2A6%2B7%2A14%2A21+%3D%5B1%2A2%2A3%2A%281%2B2%2A2%2A2%2B7%2A7%2A7%29%2F%5B1%2A3%2A5%2A%281%2B2%2A2%2A2%2B7%2A7%2A7%29%5D+%3D1%2A2%2A3%2F1%2A3%2A5+%3D2%2F5+%E4%B8%BA%E4%BB%80%E4%B9%88%E8%BF%99%E4%B9%88%E5%81%9A%3F)
1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21 =[1*2*3*(1+2*2*2+7*7*7)/[1*3*5*(1+2*2*2+7*7*7)] =1*2*3/1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21 =[1*2*3*(1+2*2*2+7*7*7)/[1*3*5*(1+2*2*2+7*7*7)] =1*2*3/1*3*5 =2/5 为什么这么做?
1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21 =[1*2*3*(1+2*2*2+7*7*7)/[1*3*5*(1+2*2*2+7*7*7)] =1*2*3/
1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21
=[1*2*3*(1+2*2*2+7*7*7)/[1*3*5*(1+2*2*2+7*7*7)]
=1*2*3/1*3*5
=2/5 为什么这么做?
1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21 =[1*2*3*(1+2*2*2+7*7*7)/[1*3*5*(1+2*2*2+7*7*7)] =1*2*3/1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21 =[1*2*3*(1+2*2*2+7*7*7)/[1*3*5*(1+2*2*2+7*7*7)] =1*2*3/1*3*5 =2/5 为什么这么做?
提取公因数可以简化过程,不用把每个数都算完再加.
还有:结果是对的,过程有误.
应该是
1*3*5+2*6*10+7*21*35分之1*2*3+2*4*6+7*14*21
=[1*2*3*(1+2+7)/[1*3*5*(1+2+7)]
=1*2*3/1*3*5
=2/5