已知函数f（x）=alnx+ex（a＞0），若f（3x）＜f（x2+2），则实数x的取值范围是______．
函数的定义域为（0，+∞）
求导函数可得：f′（x）=
+exa x
∵a＞0，x＞0
∴f′（x）＞0
∴函数f（x）在（0，+∞）上为单调增函数
∴0＜3x＜x2+2，
∴x＞0 x2-3x+2＞0
∴0＜x＜1，或x＞2
∴实数x的取值范围是（0，1）∪（2，+∞）
故答案为：（0，1）∪（2，+∞）
请仔细阅读题中的信息，从A—F 选项中找出与其相吻合的选项。 其中一项为多余选项。 小题1:She’s Amy. She’s free these days. Kids like to play with her, because she’s good at telling stories to make them happy. 小题2:Cindy is a middle school student. Her English is not good. So her parents want to find someone to help her with English on weekends. 小题3:He is Bill. He’s seventeen. He can play basketball, but he can’t play soccer. So he wants to learn to play it. 小题4:Frank is a worker with two children. They are both students. He would like to buy a house, but it must be in a quiet place, because his children need a quiet place for study. 小题5:Jerry is a student in a middle school. She knows a little about computer. So she wants to learn it on summer vacation.
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可以发生反应：2E＋I
2F＋D，F中的E元素的质量分数为60%.