If A and B are arbitrary terms, you can change A * (B) to A * B, for example 
x/(y + z) * (a * (b - c)/d/(e/f)) => x/(y + z) * a * (b - c)/d/(e/f). 

If A and B are arbitrary terms, you can change A/(B) to A/B', where B' is obtained from B by replacing all top-level "*" operations to "/" operations and vice versa, for example 
x/(y + z)/(a * (b - c)/d/(e/f)) => x/(y + z)/a/(b - c) * d * (e/f).
为什么最后(e/f)的括号没去掉

• Re:对题目的疑问 (12) muxi 2006-09-18 02:17:42