Đề Thi HSG Toán 7 - Có đáp án

TRƯNG THCS
Đ KIM TRA CHT LƯNG HỌC SINH GIỎI
NĂM HỌC 2008 - 2009

 !"#$
Bài 1:( 3 điểm)
$%&'()
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+
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+ +
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n n n n+ +
− + −
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Bài 2:(2 điểm)
BxC
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* / +
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. , ,
x
− + = − +
Bài 3: (2 điểm)
3D
a c
c b
=
03456
+ +
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a c a
b c b
+
=
+
Bài 4: (3 điểm)
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:D&DIJ103456
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TRƯNG THCS
Đ,P ,N KIM TRA CHT LƯNG HSG MÔN TO,N 7
NĂM HỌC 2008 - 2009
Bài 1:." $
$*0," $
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+ 0. 2 0.
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+ 0. 0+
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+
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n n n n−
× − × = × − ×
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Bài 2:+" $
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Bài 3: +" $

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a c a a b
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a a b a
b a b b
+
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+
Bài 4:." $
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( Hc sinh gii theo cch khc đng kt qu vn cho đim ti đa)