标题: 谁教教我这种题目怎么解，谢谢 [打印本页] 作者: gage1984 时间: 2010-3-11 11:46 标题: 谁教教我这种题目怎么解，谢谢 ps .if x^2?y^2=40 and x+y=4 what is the value of x? a. 4 b.7 c. 10. d.11 e.20 《== B
DS if ab=2 b?c=2 and bc don't = 0 what is the value of a/（bc) 1. a=1/2 2. c=1/2
ds, if n is an integer, is n?1>0 ? 1. n^2?n>0 2.n^2 =9