ʱ : ڶ 绥化中考数学试卷解析版 - 百度文库ϿʼĶ
2017ʡ绯пѧԾ
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һѡ⣨ÿС3֣30֣
1ͼֱABCDֱEFأ1=55㣬жABCDǣ
A2=35 B2=45 C2=55 D2=125
㡿J9ƽߵж
ƽߵжԸѡһжϼɣ
𡿽⣺Aɡ3=2=35㣬1=55֪1١3ʲжABCDʱѡ
Bɡ3=2=45㣬1=55֪1١3ʲжABCDʱѡ
Cɡ3=2=55㣬1=55֪1=3жABCDʱѡȷ
Dɡ3=2=125㣬1=55֪1١3ʲжABCDʱѡ ѡC
2ijҵԼΪ700000Ԫݡ700000ÿѧɱʾΪ A106
B7105 C7104 D70104
㡿1Iѧʾϴ
ѧıʾʽΪa10nʽ1|a|10nΪȷnֵʱҪԭaʱСƶ˶λnľֵСƶλͬԭֵ1ʱnԭľֵ1ʱnǸ
𡿽⣺ݡ700000ÿѧɱʾΪ7105 ѡB
3ȷǣ A3a+2a=5a2 B3a+3b=3ab C2a2bca2bc=a2bc
Da5a2=a3
㡿35ϲͬ
ֱÿһѡкϲͬɽ⣮ 𡿽⣺A3a+2a=5aAѡ B3a+3b=3a+bBѡ C2a2bca2bc=a2bcCѡȷ Da5a2=a2a31Dѡ ѡ C
4εͶӰǣ A߶
B
C D
㡿U5ƽͶӰ
ƽͶӰص㣺ͬһʱ̣ƽͶӰԾƽУɵó𰸣
𡿽⣺ͬһʱ̣ƽͶӰԾƽУõӦƽıλƽıλ߶Σ
ֽABCDͶӰΣ ѡD
5ʽĽ⼯ǣ Ax4
B2x4 C2x4 Dx2
㡿CBһԪһβʽ飮
ֱÿһʽĽ⼯ݿھͬȡͬСȡСССмҡССȷʽĽ⼯
𡿽⣺ⲻʽx13ãx4 ⲻʽx+13ãx2 ʽĽ⼯Ϊ2x4 ѡB
6ͼABCǡABCԵOΪλľλƱ任õģABCABC49OB䣺OBΪ
A23 B32 C45 D49
㡿SCλƱ任
λƱȣλƱȵƱȣεȵƱȵƽɣ
𡿽⣺λƱ任ʿ֪ABABACAC ABCסABC
ߡA'B'C'ABCı49 A'B'C'ABCƱΪ23 = ѡA
7һϴȵͨ˿ȡһţҵĸǣ A B C D
㡿X4ʹʽ
úҵ˿ƵΪĸʣ
𡿽⣺һ˿ƹ54ţк13ţһƵõҵĸǣ ѡB
8ͬһƽֱϵУֱy=4x+1ֱy=x+bĽ㲻ڣ
Aһ Bڶ C D
㡿FFֱཻƽ⣮
һκȷֱɵý 𡿽⣺ֱy=4x+1һޣ b0ʱֱy=x+bһޣ ֱ߽һޣ
b0ʱֱy=x+bޣ ֱ߽ڶޣ
ֱy=4x+1ֱy=x+bĽ㲻ڵޣ ѡD
9ij¥ݵIJͼʾѲBCijԼΪףBCAԼΪ29㣬¥ݵĸ߶ABɱʾΪ
A B C D
㡿T9ֱεӦ鶽⣮ sinACB=AB=BCsinACB=㣮 𡿽⣺RtABCУsinACB= AB=BCsinACB=㣬 ѡA
10ͼ?ABCDУACBDཻڵOEOAе㣬BEӳADڵF֪SAEF=4нۣ =SBCE=36SABE=12ܡAEFACDһȷǣ
A٢ڢۢ B٢ Cڢۢ D٢ڢ
㡿S9εжʣL5ƽıεʣ
ƽıεʵõAE=CEεʵõ==õAF=ADǵõ=ʢȷεʵõSBCE=36ʢȷεʽõSABE=12ʢȷڡAEFADC