GWD 19 - 11

detectiveyan

Q11:

If |x| < 1?

(1) |x + 1| = 2|x - 1|

(2) |x - 3| ≠ 0

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

D. EACH statement ALONE is sufficient.

E. Statements (1) and (2) TOGETHER are NOT sufficient.
Answer: C

Thanks!

merit

条件1两边平方得到一个一元二次方程，解此方程得x=1/3或者x=3，再结合条件2，可以知道|x|<1

woodruff1

up!!!!!!!!!