2015年中考真题
MCPDHFEANB26.
⑴y??3x?63
⑵E'M??F'N??
3232m?3m?33?(?3m?63)??m?23m?33 4432m?3m 432m?33m?33 故:E'M?F'N??2当m??332?(?3)2?3时,E'M?F'N最大,
1537)F'(5,3) 4427∴E'F':y??3x?3 427∴R(0,3),RF'?RE'max?4
4⑶由题意,Q点在?CAB的角平分线或外角平分线上
此时E'(3,①当Q点在?CAB的角平分线上时,如图
Q'M?Q'N?3,CW?31
9393?3 ,则RN?222?31△CRN∽△CWO,故CN? 32?3110?31?∴DN=CD-CN=4? 331313?2093故S? 27△RMQ’∽△RNC,故RQ'?2015年中考真题
yCRWG'GMQ'CNQxDP'PB
②当Q点在?CAB的外角平分线上时,如图 9393?3 ,故RM?2231?2△RCM∽△WCO,故CM= 3△Q’RN∽△WCO,故Q'R?在Rt△Q’MP’中,AM'?3Q'M?3,故CP'?MP'?CM?3?在Rt△CP’S中,P'S?故S=
yC31?211?31? 333311?31CP?? 223763?1193
12WG'GQ'MNSQxCP'ODPBR
[来源:Z#xx#k.Com]
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