ʱ : 江苏省淮安市2018_2019学年高一数学下学期期末考试试题 - 百度文库ϿʼĶ
֤̻㲽裮
17.֪A(50)B(32)C(02) 1ֱABķ̣
2BCе㵽ֱABľ룮 𰸡(1)x-4y-5=02
(1)ֱߵĵбʽֱABķ̣2õ㵽ֱߵľBCе㵽ֱABľ룮
⡿1kAB?1317. 34?2?01?,
?3?541(x?5),?x?4y?5?0. 4ֱABķΪy?0?-,0) (2)BCеΪ
3|??5|13BCе㵽ֱABľΪ2?17. 12+4234㾦Ҫֱ߷̵㵽ֱߵľڿѧЩ֪ʶˮƽͷ.
18.ͼڡABCУB30㣬DBCһ㣬AD42CD7AC5
32
1ADCĴС 2ABij 𰸡145028
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(1)ҶADCĴС2ҶABij ⡿1Ҷcos?ADC?2áADB=135,
032?49?252?,??ADC?450. 22?42?7Ҷ
42AB?,?AB?8. 00sin30sin135㾦ҪҶҶΣڿѧЩ֪ʶˮƽͷ.
19.˶ԱֱڸԲͬ5ľҶͼͼʾ֪˶Աڸ5ƽΪ10
1xyֵ
22ķSSңָλ˶Աˮƽȶ
23ԱҪԼ˶ԱˮƽڼҸԵ5иѡһ˶Ա֮С18ĸʣ 𰸡1x=2,y=9;(2)S=
2(1)ƽx,yֵ2ķSSңжλ˶Ա
22126S2=2Ҹȶ3. 55ˮƽȶ3ùŵ͵ĸ˶Ա֮С18ĸʣ ⡿18+7+30+3?x?0?50,?x?2
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8?y?30?0?1?2?50,?y?9.
(2)S=[(8?10)?(7?10)?(13?10)?(12?10)?(10?10)]?2152222226 5110S2=[(8?10)2?(9?10)2?(11?10)2?(12?10)2?(10?10)2]?=2.
55Ϊ2?26˶Աˮƽȶ. 5(3)еĻ¼У8,88,98,108,118,127,87,97,107,117,1210,810,910,1010,1110,1212812,912,1012,1112,1213,813,913,1013,1113,12.25.
˶Ա֮С18Ļ¼У8,88,97,87,97,105,
ɹŵ͵ĸʹʽ˶Ա֮С18ĸΪ
51=. 255㾦Ҫƽļͷļ㣬ŵ͵ĸʵļ㣬ڿѧЩ֪ʶˮƽͷ.
20.ͼPABCУPBCΪȱΣOΪBCе㣬ACPBƽPBCƽABC
1ֱPBƽABCɵĽǵĴС 2֤ƽPACƽPBC
3֪EΪPOе㣬FABϵĵ㣬AF?ABEFƽPAC?ֵ 𰸡16002֤3?=
1 3- 11 -
1ҵֱPBƽABCɵĽΪ?PBO,С2֤PO?AC, ֤ƽPACƽPBC3ȡCOеG,EG,GFG||AC,?ֵ. ⡿1
ƽPBCƽABCPOBC, ƽPBCƽABC=BC,PO?ƽPBC,
POƽABC,
ֱPBƽABCɵĽΪ?PBO, Ϊ?PBO=600 ֱPBƽABCɽΪ600.
(2)ΪPOƽABC, PO?AC,
ΪACPBPO,PB?ƽPBC,POIPB?P, ACƽPBC, ΪAC?ƽPAC, ƽPACƽPBC. (3)
ȡCOеG,EG,GFG||AC, EG||PC,EG||ƽAPC, ΪFG||ACFG||ƽPAC, EG,FG?ƽEFO,EGFG=G, ƽEFO||ƽPAC,
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