已知x＞y＞z且x+y+z=0则下列不等式一定成立的是()A.xy＞yzB.xz＞yzC.zy＞xzD.x|y|＞z|y|
A.xy＞yz B.xz＞yz
C.zy＞xz D.x|y|＞z|y|
解析:∵x＞y＞z x+y+z=0 ∴x＞0 z＜0.又x＞y 则xz＜yz.
答案:C
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