一道化简数学题=[1/3*X+2/5*(115-X)]*10+[2/3*X+(115-X)*3/5]*5

问题描述:

一道化简数学题
=[1/3*X+2/5*(115-X)]*10+[2/3*X+(115-X)*3/5]*5

[1/3*X+2/5*(115-X)]*10+[2/3*X+(115-X)*3/5]*5
=(1/3*X)*10+(2/3*X)*5+(115-X)(20/5+15/5)
=20x/3-7x+805
=-x/3+805
应该对

[1/3*X+2/5*(115-X)]*10+[2/3*X+(115-X)*3/5]*5
=(1/3*X)*10+(2/3*X)*5+(115-X)(20/5+15/5)
=20x/3-7x+805
=-x/3+805

中括号去掉得到:原式=(10/3x+460-4x)+(10/3x+230-3x) =10/3x(460-4x+230-3x) =10/3x(690-7x)[1/3*X+2/5*(115-X)]*10+[2/3*X+(115-X)*3/5]*5 =(1/3*X)*10+(2/3*X)*5+(115-X...