
第Ⅰ卷
一、選擇題(本大題共8個(gè)小題,每小題3分,共24分.在每個(gè)小題給出的四個(gè)選項(xiàng)中,只有一項(xiàng)符合題目要求,請(qǐng)選出并在答題卡上將該項(xiàng)涂黑)
第Ⅱ卷
二、填空題(本大題共10小題,每小題3分,共30分)
9.3.84×10510.811.7或9或1112.26°
13.1214.24°15.40°或75°或130°16.10
17.m<1818.2-2或1或2
三、解答題(本大題共10個(gè)小題,共86分.解答應(yīng)寫出文字說(shuō)明,證明過(guò)程或演算步驟)
19.(10分)
解:(1)原式=1+2﹣4+14
=-34;·······································································5分
(2)原式=2xx+1-2(x+3)(x+1)(x-1)?(x-1)2x+3
=2xx+1-2(x-1)x+1
=2x+1.·······································································10分
20.(10分)
解:(1)3x+2y=13①2x+3y=-8②,
①×3﹣②×2,得:5x=55,
解得x=11,
將x=11代入①,得:33+2y=13,
解得:y=﹣10.
∴方程組的解為x=11y=-10;····························································5分
(2)5y-23-1>3y-522(y-3)≤0,
解第一個(gè)不等式得x>﹣5,
解第二個(gè)不等式得y≤3.
故不等式組的解集為﹣5<y≤3.·······················································10分
21.(6分)
解:(1)90÷30%=300,
故答案為:300;······································································2分
(2)合唱人數(shù):300×10%=30(人),
舞蹈人數(shù):300﹣120﹣90﹣30=60(人),
補(bǔ)全條形統(tǒng)計(jì)圖如圖所示:
····················································4分
(3)800×30+60300=240(人),
答:該校喜歡合唱和舞蹈社團(tuán)的學(xué)生共有240人.··········································6分
22.(8分)
解:(1)第一次摸出一個(gè)球,球上的數(shù)字是偶數(shù)的概率是13,
故答案為:13;··········································································4分
(2)畫樹狀圖如下:
························································6分
共有9種等可能的結(jié)果,其中兩次摸出球上的數(shù)字的積為奇數(shù)的結(jié)果有4種,
∴兩次摸出球上的數(shù)字的積為奇數(shù)的概率為49.·············································8分
23.(7分)
解:設(shè)B品牌的呼吸機(jī)每臺(tái)的進(jìn)價(jià)是x萬(wàn)元,則A品牌的呼吸機(jī)每臺(tái)的進(jìn)價(jià)是(x+0.2)萬(wàn)元,
依題意,得:20x+0.2=18x,·····························································4分
解得:x=1.8,
經(jīng)檢驗(yàn):x=1.8是原方程的解,且符合題意,
∴x+0.2=2.·········································································7分
答:A品牌的呼吸機(jī)每臺(tái)的進(jìn)價(jià)是2萬(wàn)元,B品牌的呼吸機(jī)每臺(tái)的進(jìn)價(jià)是1.8萬(wàn)元.
24.(8分)
(1)證明:連接OD,
∵OA=OD,
∴∠OAD=∠ODA,
∵AD平分∠BAC,
∴∠OAD=∠BAD,
∴∠ODA=∠BAD,
∴OD∥AB,
∴∠ODC=∠B=90°,
∴半徑OD⊥BC于點(diǎn)D,
∴BC是⊙O的切線;··································································3分
(2)解:連接 OF,DE,
∵∠B=90°,tan∠ADB=3,
∴∠ADB=60°,∠BAD=30°,
∵BD=5,
∴AD=2BD=10,
∵AE是⊙O的直徑,
∴∠ADE=90°,
∵AD平分∠BAC,
∴∠DAE=∠BAD=30°,
在 Rt△ADE 中,AD=10,
∵cs∠DAE=ADAE=32,
∴AE=2033,
∴OA=12AE=1033,
∵AD平分∠BAC,
∴∠BAC=2∠BAD=60°,
∵OA=OF,
∴△AOF 是等邊三角形,
∴∠AOF=60°,
∵OD∥AB,
∴S△ADF=S△AOF,
∴S陰影=S扇形OAF=60π×(1033)2360=50π9.················································8分
25.(7分)
解:延長(zhǎng)AC交EF于點(diǎn)G,
由題意得:AC=BD=1.8米,AB=CD=FG=0.8米,
設(shè)CG=x米,則AG=AC+CG=(x+1.8)米,
在Rt△AEG中,∠EAG=45°,
∴EG=AG?tan45°=(x+1.8)米,·······················································3分
在Rt△ECG中,∠ECG=53°,
∴EG=CG?tan53°≈1.33x(米),
∴x+1.8=1.33x,
解得:x=6011,
∴EF=EG+FG=1.33×6011+0.8≈8.1(米),
∴電池板離地面的高度EF的長(zhǎng)約為8.1米.···············································7分
26.(10分)
解:(1)如圖,連接OB′、AB′,
∵四邊形OABC為矩形,A(4,0),C(0,m),
∴B(4,m),OA=4,OC=m,
∵將矩形OABC繞點(diǎn)O逆時(shí)針旋轉(zhuǎn)90°得到矩形OA′B′C′,
∴A′(0,4),C′(﹣m,0),B′(﹣m,4),
∴B′C⊥x軸,B′C=4,
∴S△OAB′=12×4×4=8,
∴△OAB′的面積是8.··································································3分
(2)如圖①,連接A′A,∵∠A′OA=90°,OA′=OA=4,
∴AA′=OA'2+OA2=42+42=42,
∵四邊形OA′B′C′是矩形,OB′、A′C′交于點(diǎn)D,
∴C′D=A′D,
∵AD⊥A′C′,
∴AC′=AA′=42,
∴OC′=AC′﹣OA=42-4,
∴OC=OC′=42-4,
∴C(0,42-4),
∴m的值是42-4.··································································6分
(3)如圖②,∵四邊形OCEF是平行四邊形,
∴EF∥OC,EF=OC=m,
∴∠EFB=∠A′CB=90°,
∴EF⊥BC,
∵E是A′B的中點(diǎn),
∴CE=BE=A′E=12A′B,
∴CF=BF,
∴A′C=2EF=2m,
∵A′C+OC=4,
∴2m+m=4,
解得m=43,
∴m的值是43.·······································································10分
27.(10分)
解:(1)∵拋物線y=x2+bx+c經(jīng)過(guò)點(diǎn)B(1,0),C(0,﹣3),
∴1+b+c=0c=-3,
解得:b=2c=-3,
∴拋物線的函數(shù)表達(dá)式為:y=x2+2x﹣3.················································2分
(2)①當(dāng)x=0時(shí),y=x2+2x﹣3=﹣3,
∴點(diǎn)C(0,﹣3).
當(dāng)y=0時(shí),x2+2x﹣3=0,
解得:x1=﹣3,x2=1,
∴A(﹣3,0),
設(shè)直線AC的解析式為y=kx+n,
把A(﹣3,0),C(0,﹣3)代入,
得:-3k+n=0n=-3,解得:k=-1n=-3,
∴直線AC的解析式為:y=﹣x﹣3.
∵OA=OC=3,
∴∠OAC=∠OCA=45°.
過(guò)點(diǎn)E作EK⊥y軸于點(diǎn)K,
∵EG⊥AC,
∴∠KEG=∠KGE=45°,
∴EG=EKsin45°=2EK=2OD,
設(shè)P(m,m2+2m﹣3),則E(m,﹣m﹣3),
∴PE=﹣m﹣3﹣(m2+2m﹣3)=﹣m2﹣3m,
∴PE+2EG=PE+2OD=﹣m2﹣3m﹣2m=﹣m2﹣5m=﹣(m+52)2+254,
由題意有﹣3<m<0,且﹣3<-52<0,﹣1<0,
當(dāng)m=-52時(shí),PE+2EG取最大值,PE+2EG的最大值為254;······························5分
②作EK⊥y軸于K,F(xiàn)M⊥y軸于M,記直線EG與x軸交于點(diǎn)N.
∵EK⊥y軸,PD⊥x軸,∠KEG=45°,
∴∠DEG=∠DNE=45°,
∴DE=DN.
∵∠KGE=∠ONG=45°,
∴OG=ON.
∵y=x2+2x﹣3的對(duì)稱軸為直線x=﹣1,
∴MF=1,
∵∠KGF=45°,
∴GF=MFsin45°=2MF=2.
∵∠FDG=45°,
∴∠FDN=∠DEG.
又∵∠FDG=∠DEG,
∴△DGF∽△EGD,
∴DGFG=EGDG,
∴DG2=FG?EG=2×2(﹣m)=﹣2m,
在Rt△ONG中,OG=ON=|OD﹣DN|=|OD﹣DE|=|﹣m﹣(m+3)|=|﹣2m﹣3|,OD=﹣m,
在Rt△ODG中,
∵DG2=OD2+OG2=m2+(2m+3)2=5m2+12m+9,
∴5m2+12m+9=﹣2m,
解得m1=﹣1,m2=-95.·······························································10分
28.(10分)
(1)解:∵四邊形ABCD是正方形,
∴AB=CD=AD,∠BAD=∠C=∠D=90°,
由旋轉(zhuǎn)的性質(zhì)得:△ABE≌△ADM,
∴BE=DM,∠ABE=∠D=90°,AE=AM,∠BAE=∠DAM,
∴∠BAE+∠BAM=∠DAM+∠BAM=∠BAD=90°,
即∠EAM=90°,
∵∠MAN=45°,
∴∠EAN=90°﹣45°=45°,
∴∠MAN=∠EAN,
在△AMN和△AEN中,
AM=AE∠MAN=∠EANAN=AN,
∴△AMN≌△AEN(SAS),
∴MN=EN,
∵EN=BE+BN=DM+BN,
∴MN=BN+DM,
在Rt△CMN中,由勾股定理得:MN=CN2+CM2=62+82=10,
則BN+DM=10,
設(shè)正方形ABCD的邊長(zhǎng)為x,則BN=BC﹣CN=x﹣6,DM=CD﹣CM=x﹣8,
∴x﹣6+x﹣8=10,
解得:x=12,
即正方形ABCD的邊長(zhǎng)是12;
故答案為:12;·······································································3分
(2)證明:設(shè)BN=m,DM=n,
由(1)可知,MN=BN+DM=m+n,
∵∠B=90°,tan∠BAN=13,
∴tan∠BAN=BNAB=13,
∴AB=3BN=3m,
∴CN=BC﹣BN=2m,CM=CD﹣DM=3m﹣n,
在Rt△CMN中,由勾股定理得:(2m)2+(3m﹣n)2=(m+n)2,
整理得:3m=2n,
∴CM=2n﹣n=n,
∴DM=CM,
即M是CD的中點(diǎn);··································································6分
(3)解:延長(zhǎng)AB至P,使BP=BN=4,過(guò)P作BC的平行線交DC的延長(zhǎng)線于Q,延長(zhǎng)AN交PQ于E,連接EM,如圖③所示:
則四邊形APQD是正方形,
∴PQ=DQ=AP=AB+BP=12+4=16,
設(shè)DM=a,則MQ=16﹣a,
∵PQ∥BC,
∴△ABN∽△APE,
∴BNPE=ABAP=1216=34,
∴PE=43BN=163,
∴EQ=PQ﹣PE=16-163=323,
由(1)得:EM=PE+DM=163+a,
在Rt△QEM中,由勾股定理得:(323)2+(16﹣a)2=(163+a)2,
解得:a=8,
即DM的長(zhǎng)是8;
故答案為:8.·········································································10分1
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