[原创]GWD-28-34疑问

wisdomcorn

Q34:The operation Θ is defined by x Θ y =  +  for all nonzero numbers x and y.  If z is a number greater than 1, which of the following must be true?

  I.  x Θ (-z) = 0

        II.  z Θ  = 1

       III.  
                         Θ  = z

 

 

A.    I only

B.    I and II only

C.    I and III only

D.    II and III only

E.    I, II, and III

  Answer   正确答案E    不明白1怎么正确. 请大家帮我解答下.谢谢

wisdomcorn

自己顶一下!

这道题baidu没搜到,所以贴上来.哪位牛牛,能给下思路啊?

wisdomcorn

the answer is false, the D is correct, I met the same question in GWD23.