(1)解一元二次方程:x
2-2x-4=0;
(2)将4个数a,b,c,d排成2行、2列,两边各加一条竖直线记成
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000342952766278/SYS201311030003429527662016_ST/0.png)
,定义
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000342952766278/SYS201311030003429527662016_ST/1.png)
=ad-bc,上述记号就叫做2阶行列式.若
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000342952766278/SYS201311030003429527662016_ST/2.png)
=8x,则x=______
考点分析:
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