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将矩形ABCD沿AE折叠,使点D落在D′处,已知∠CED′=60°,DE=1,则...
将矩形ABCD沿AE折叠,使点D落在D′处,已知∠CED′=60°,DE=1,则DD′的长为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101193716221132325/SYS201311011937162211323008_ST/images0.png)
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101193716221132325/SYS201311011937162211323008_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101193716221132325/SYS201311011937162211323008_ST/1.png)
C.2
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101193716221132325/SYS201311011937162211323008_ST/2.png)
D.3
考点分析:
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正比例函数y=x与反比例函数y=
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的图象相交于A、C两点.AB⊥x轴于B,CD⊥y轴于D(如图),则四边形ABCD的面积为( )
A.1
B.
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C.2
D.
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二次函数y=ax
2+bx+c的图象如图所示,则下面四条信息:
①b
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你认为正确的是( )
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B.①③④
C.②③④
D.①②
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如图,CD是⊙O的直径,AB是弦(不是直径),AB⊥CD于点E,则下列结论正确的是( )
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A.AE>BE
B.
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=
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C.∠D=
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∠AEC
D.△ADE∽△CBE
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化简
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C.-
D.
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