[原创]CD【Math机经月总结】03-31

無味

sorry suppose on the answer of question 20, i just found out that the answer is A
because if Y is lesser than 0, then either X or Z is negative, then the answer must be lesser than 0

hexin

20. I think the answer is A.
(1), when Y<0, then if x<0, z>0, if x>0, z<0. therefore XY^2Z>0 definitely.
(2), when x<0, then if y<0, z>0, if y>0, z<0. we cannot know whether XY^2Z>0

hexin

22. I think 44 is also correct. for examply n can be 44, 92.... If we encounter this question, we should be careful.

無味

i have a question on the problem 18, i think the answer should be C
because statement 1 & 2 cannot solve the question alone. but if together, then
x^(1/2)>y, and x>y^(1/2), then x must be a positive number, because if x is negative, then y must be negative, but if y is negative number, then i cannot square root.
Therefore, x and y must be positive
As the result, x>y

yumi55

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