RT
Q17:
In the figure, points A, B, C, D, and E lie on a line. A is on both circles, B is the center
of the smaller circle, C is the center of the larger circle, D is on the smaller circle, and E
is on the larger circle. What is the area of the region inside the larger circle and outside
the smaller circle?
(1) AB = 3 and BC =2
(2) CD =1 and DE = 4
（不看图也可以，我太笨，不会作图，呵呵）答案选A，我选D，因为可以求出CE=5，即大圆半径，再乘2减4即小圆直径。
Q32:
If xyz ≠ 0, is x (y + z) = 0?
(1) |y + z| = |y| + |z|
(2) |x + y| = |x| + |y|
答案选C，我选A, 因为A即可否定yz两者互为倒数的可能。
Q35:
Stations X and Y are connected by two separate, straight, parallel rail lines that are 250
miles long. Train P and train Q simultaneously left Station X and Station Y, respectively,
and each train traveled to the other’s point of departure. The two trains passed each other
after traveling for 2 hours. When the two trains passed, which train was nearer to its
destination?
(1) At the time when the two trains passed, train P had averaged a speed of 70 miles
per hour.
(2) Train Q averaged a speed of 55 miles per hour for the entire trip.
答案选C,我选A，因为可求出在相遇时P已经走了140miles，大于全程一半。
请各位帮忙，非常感谢！
第一题：
两个条件分别能独立得出解，大圆半径5，小圆半径3。
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第二题：
条件一，得出y*z>0,即y,z同号，那么肯定单独推不出x(y+z)=0
条件二，得出x*y>0,即x,y同号，x(y+z)是不是等于零，不一定。
两个条件综合一下，就是x*y^2*z>0,即xz>0,既然xy>0,xz>0,那么x(y+z)>0
不知道答案C是什么选项？
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第三题：
如果都是匀速，两个条件是一样的，就是P走了140公里的地方。应该是P离终点更近。
嘻嘻，谢谢LS热心，原来是我的GWD印刷有问题，第二道是问是否不小于0~
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