题目内容
抛物线y=2x2-3x+l的顶点坐标为( )A.(-
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_ST/0.png)
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_ST/1.png)
B.(
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_ST/2.png)
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_ST/3.png)
C.(
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_ST/4.png)
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_ST/5.png)
D.(-
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_ST/6.png)
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_ST/7.png)
【答案】分析:将抛物线一般式配方为顶点式,可求抛物线顶点坐标.
解答:解:配方得:y=2x2-3x+1=2(x-
)2-
,
∴抛物线顶点坐标为(
,-
).
故选B.
点评:本题考查了二次函数的性质.关键是利用配方法将抛物线一般式转化为顶点式,确定顶点坐标.
解答:解:配方得:y=2x2-3x+1=2(x-
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_DA/0.png)
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_DA/1.png)
∴抛物线顶点坐标为(
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_DA/2.png)
![](http://thumb.zyjl.cn/pic6/res/czsx/web/STSource/20131022162928892289528/SYS201310221629288922895002_DA/3.png)
故选B.
点评:本题考查了二次函数的性质.关键是利用配方法将抛物线一般式转化为顶点式,确定顶点坐标.
![](http://thumb.zyjl.cn/images/loading.gif)
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