GWD 18-9

不知不觉

Q9:

Is x < 0 ?

(1)   x³ < x²

(2)   x³ < x⁴

^{ANS : C}

t5oct2005

1. x^2(x-1)<0 => x<1 && x<>0 insufficient

2. x^3(1-x)<0 => x<0 || x>1 insufficient

1&2: x<0 DONE!

不知不觉

谢谢GG.

偶又傻掉了

amy1949

哪里可以下载GWD17-19

elfgoer

1. x^2(x-1)<0 => x<1 && x<>0 insufficient -->是不是寫錯了?應該是x<1而已,所以(1)insufficient

2. x^3(1-x)<0 => x<0 || x>1 insufficient