如果3＜a＜5，复数z=（a2-8a+15）+（a2-5a-14）i在复平面上的

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问题填空题

如果3＜a＜5，复数z=（a²-8a+15）+（a²-5a-14）i在复平面上的对应点a在______象限．

答案

∵3＜a＜5，a²-8a+15=（a-3）（a-5）＜0，a²-5a-14=（a+2）（a-7）＜0，所以复数在复平面上的对应点a在第三象限．

故答案为：三．

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