考点二十三

1、考点二十三不等式选讲 解答题1已知函数fxx1x2.1求不等式2fx2mn.解1依题意,fxx1x2由22x10,解得x,故A.2证明:m,nA,由1可知,m2,n20,所以14mn24mn2,故14mn2mn.2已知fxx2xa.1当a4。

2、考点二十三七选五 Passage 1限时8分钟Technological innovation 创新 may not give you a warm feeling 1 Messaging apps are examples of tech。