锟竭讹拷锟斤拷(sh锟斤拷)锟絎(xu锟斤拷)锟斤拷锟斤拷?g锟斤拷u)?f锟斤拷)锟斤拷(x锟斤拷)锟絵锟斤拷锟斤拷
2009-02-27 16:55:34锟斤拷站原锟斤拷(chu锟斤拷ng)
锟斤拷锟斤拷锟竭讹拷锟斤拷(sh锟斤拷)锟絎(xu锟斤拷)锟斤拷锟斤拷?g锟斤拷u)?f锟斤拷)锟斤拷(x锟斤拷)锟絵锟斤拷锟斤拷
锟斤拷锟斤拷锟絝(shu锟斤拷)锟斤拷锟斤拷1锟斤拷锟斤拷試锟斤拷锟街第拷锟斤拷锟斤拷x锟斤拷锟絵锟斤拷锟酵第拷锟斤拷锟斤拷锟斤拷x锟斤拷锟絵锟斤拷锟缴诧拷锟斤拷锟斤拷
锟斤拷锟斤拷2锟斤拷锟斤拷150锟街ｏ拷锟斤拷試锟絩(sh锟斤拷)锟絞120锟斤拷锟�锟斤拷
锟斤拷锟斤拷锟节拷锟斤拷锟斤拷x锟斤拷锟絵锟斤拷60锟街ｏ拷
锟斤拷锟斤拷一锟斤拷锟絰锟斤拷锟絵锟斤拷锟斤拷锟斤拷锟絵锟斤拷12小锟絵锟斤拷每小锟絵5锟斤拷锟斤拷锟斤拷60锟斤拷锟斤拷锟斤拷每小锟絵锟給锟斤拷锟斤拷锟侥傦拷(g锟斤拷)锟絰锟�(xi锟斤拷ng)锟斤拷锟斤拷只锟斤拷一锟�(xi锟斤拷ng)锟角凤拷锟斤拷锟絵目要锟斤拷模锟�
锟斤拷锟斤拷1锟斤拷锟斤拷a>b锟斤拷锟絫锟斤拷锟叫诧拷锟斤拷式锟斤拷1锟斤拷a+c>b+c锟斤拷锟斤拷2锟斤拷a锟斤拷c>b锟斤拷c锟斤拷锟斤拷3锟斤拷ac>bc锟斤拷锟斤拷4锟斤拷>锟斤拷c>0锟斤拷锟斤拷锟叫猴拷锟斤拷锟斤拷牟锟斤拷锟绞斤拷锟�(g锟斤拷)锟斤拷(sh锟斤拷)锟介（锟斤拷
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锟斤拷锟斤拷2.锟絕(gu锟斤拷)锟絚(di锟斤拷n)锟斤拷1锟斤拷0锟斤拷锟斤拷锟斤拷锟絚直锟斤拷平锟叫碉拷直锟斤拷锟斤拷锟斤拷锟斤拷()
锟斤拷锟�锟斤拷锟紸锟斤拷锟斤拷B锟斤拷
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锟斤拷锟斤拷3.锟斤拷锟斤拷锟絚(di锟斤拷n)A锟斤拷-3锟斤拷0锟斤拷锟斤拷B锟斤拷3锟斤拷0锟斤拷锟斤拷锟絰之锟斤拷慕^锟斤拷(du锟斤拷)值锟斤拷锟斤拷6锟斤拷锟絚(di锟斤拷n)锟斤拷軌锟紼锟角ｏ拷锟斤拷
锟斤拷锟�锟斤拷锟紸锟斤拷锟紼锟紸锟斤拷B锟斤拷锟斤拷锟轿ｏ拷C锟斤拷锟絧锟斤拷锟斤拷锟斤拷D锟斤拷锟缴條锟戒線
锟斤拷锟斤拷4.锟斤拷锟斤線锟侥滐拷(zh锟斤拷n)锟斤拷锟斤拷锟斤拷锟角ｏ拷锟斤拷
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锟斤拷锟斤拷5.锟紸=25锟斤拷x锟絊锟较截得碉拷锟斤拷锟絃(zh锟斤拷ng)锟角ｏ拷锟斤拷
锟斤拷锟斤拷锟斤拷A锟斤拷3??锟斤拷B锟斤拷4锟斤拷C锟斤拷6锟斤拷D锟斤拷8锟斤拷
锟斤拷锟斤拷6锟絚锟斤拷锟斤拷式同锟斤拷牟锟斤拷锟绞斤拷椋拷锟�
锟斤拷锟�锟斤拷锟紸锟斤拷锟斤拷B锟斤拷
锟斤拷锟�锟斤拷锟紺锟斤拷lg>0锟斤拷D锟斤拷
锟斤拷锟斤拷7.锟絰锟斤拷锟绞烇拷锟斤拷一锟斤拷(g锟斤拷)锟斤拷锟絚(di锟斤拷n)锟角ｏ拷5锟斤拷0锟斤拷锟斤拷锟絧锟斤拷锟斤拷锟侥橈拷(bi锟斤拷o)锟斤拷(zh锟斤拷n)锟斤拷锟斤拷锟角ｏ拷锟斤拷
锟斤拷锟�锟斤拷锟紸锟斤拷锟斤拷B锟斤拷
锟斤拷锟�锟斤拷锟紺锟斤拷锟斤拷D锟斤拷
锟斤拷锟斤拷8.[原锟絵锟結锟斤拷锟斤拷锟絗]锟斤拷知锟斤拷锟絚(di锟斤拷n)M锟斤拷1锟斤拷??锟斤拷锟斤拷N锟斤拷?锟斤拷?锟斤拷锟斤拷锟絫M锟絇(gu锟斤拷n)锟斤拷N锟侥岋拷(du锟斤拷)锟絈锟絚(di锟斤拷n)锟斤拷锟斤拷锟斤拷(bi锟斤拷o)锟斤拷()
锟斤拷锟斤拷??锟斤拷A锟斤拷锟斤拷1锟斤拷?锟斤拷锟斤拷B锟斤拷锟斤拷1锟斤拷?锟斤拷??锟斤拷C锟斤拷锟斤拷1锟斤拷3锟斤拷???????锟斤拷D锟斤拷锟斤拷?锟斤拷?3锟斤拷
锟斤拷锟斤拷9.锟斤拷锟斤拷式锟組锟斤拷示锟侥區(q锟斤拷)锟斤拷锟斤拷()
锟斤拷锟斤拷10.锟斤拷锟絚(di锟斤拷n)A锟斤拷1锟斤拷3锟斤拷锟斤拷B锟斤拷锟斤拷2锟斤拷8锟斤拷锟斤拷C锟斤拷7锟斤拷5锟斤拷锟斤拷锟斤拷c(di锟斤拷n)锟斤拷ABC锟斤拷
锟斤拷锟斤拷A锟斤拷直锟斤拷锟斤拷锟斤拷锟斤拷B锟斤拷锟絁锟斤拷锟斤拷锟斤拷锟斤拷
锟斤拷锟斤拷C锟斤拷锟絞锟斤拷锟斤拷锟斤拷锟斤拷D锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷
锟斤拷锟斤拷11.锟斤拷知锟紼锟紸锟斤拷锟斤拷一锟絚(di锟斤拷n)P锟斤拷锟斤拷锟斤拷锟紼锟紸锟斤拷锟�(zh锟斤拷n)锟斤拷锟侥撅拷锟絰锟斤拷锟斤拷锟絚(di锟斤拷n)P锟斤拷锟揭斤拷锟絚(di锟斤拷n)锟侥撅拷锟絰锟斤拷锟斤拷锟斤拷锟斤拷锟絚(di锟斤拷n)锟斤拷锟絰锟侥幾憋拷()
锟斤拷锟斤拷锟斤拷A锟斤拷7锟斤拷B锟斤拷6???????????????锟斤拷C锟斤拷5锟斤拷D锟斤拷
锟斤拷锟斤拷12.锟斤拷锟斤拷锟教憋拷示锟斤拷锟斤拷锟斤拷锟斤拷()
锟斤拷锟斤拷A锟斤拷锟斤線锟斤拷一锟斤拷B锟斤拷锟斤拷C锟紸锟斤拷一锟斤拷锟斤拷D锟斤拷锟斤線
锟斤拷锟斤拷锟节拷锟斤拷锟斤拷锟斤拷x锟斤拷锟絵锟斤拷90锟街ｏ拷
锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷}锟斤拷锟斤拷锟斤拷锟絵锟斤拷4小锟絵锟斤拷每小锟絵4锟斤拷锟斤拷锟斤拷16锟街★拷锟窖达拷锟斤拷锟斤拷锟絵锟叫橫锟斤拷锟较ｏ拷
锟斤拷锟斤拷13.锟斤拷锟斤拷(sh锟斤拷)锟斤拷x锟斤拷0锟斤拷锟斤拷锟斤拷小值锟斤拷锟斤拷
锟斤拷锟斤拷14锟斤拷锟絕(gu锟斤拷)锟絚(di锟斤拷n)C锟斤拷-1锟斤拷1锟斤拷锟斤拷D锟斤拷1锟斤拷3锟斤拷锟斤拷锟紸锟斤拷锟斤拷X锟絊锟较的圓锟侥凤拷锟教烇拷锟斤拷
锟斤拷锟斤拷15.锟斤拷知F1锟斤拷F2锟角橢锟紸+y2=1锟侥兩傦拷(g锟斤拷)锟斤拷锟絚(di锟斤拷n),P锟斤拷該锟紼锟紸锟较碉拷一锟斤拷(g锟斤拷)锟斤拷(d锟斤拷ng)锟絚(di锟斤拷n),锟絫|PF1|·|PF2|锟斤拷锟斤拷锟街碉拷锟�.
锟斤拷锟斤拷16锟斤拷D锟斤拷锟斤拷锟斤線锟轿癸拷锟斤拷锟斤拷锟絚(di锟斤拷n)锟斤拷水锟斤拷2锟阶時(sh锟斤拷)锟斤拷锟統(c锟斤拷)锟矫癸拷锟斤拷锟�(n锟斤拷i)水锟芥寬锟斤拷12锟斤拷锟斤拷锟斤拷(d锟斤拷ng)水锟斤拷锟斤拷锟斤拷1锟阶猴拷锟斤拷锟斤拷锟斤拷锟�(n锟斤拷i)水锟芥寬锟斤拷锟斤拷锟斤拷
锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷}锟斤拷锟斤拷锟斤拷锟絵锟斤拷6小锟絵锟斤拷锟斤拷74锟斤拷锟斤拷锟斤拷锟斤拷}锟斤拷(y锟斤拷ng)锟斤拷(xi锟斤拷)锟斤拷锟斤拷锟斤拷锟絝(shu锟斤拷)锟斤拷锟斤拷锟紺锟斤拷锟絕(gu锟斤拷)锟教伙拷锟斤拷锟姐步锟紼锟斤拷
锟斤拷锟斤拷17.锟斤拷锟斤拷锟絵锟組锟斤拷12锟街ｏ拷
锟斤拷锟斤拷锟解不锟斤拷式
锟斤拷锟斤拷18.锟斤拷锟斤拷锟絵锟組锟斤拷12锟街ｏ拷
锟斤拷锟斤拷锟斤拷平锟斤拷直锟斤拷锟斤拷锟斤拷(bi锟斤拷o)系xOy锟斤拷锟斤拷锟斤拷ABC锟斤拷锟斤拷c(di锟斤拷n)B锟斤拷C锟斤拷锟斤拷锟斤拷(bi锟斤拷o)锟街別锟介（3锟斤拷0锟斤拷锟斤拷锟斤拷3锟斤拷0锟斤拷锟斤拷锟斤拷锟斤拷ABC锟斤拷锟斤拷锟絃(zh锟斤拷ng)锟斤拷16锟斤拷锟絫锟斤拷c(di锟斤拷n)A锟斤拷軌锟紼锟斤拷锟斤拷
锟斤拷锟斤拷19.锟斤拷锟斤拷锟絵锟組锟斤拷12锟街ｏ拷
锟斤拷锟�锟斤拷锟�1锟斤拷锟斤拷锟絕(gu锟斤拷)锟絚(di锟斤拷n)A锟斤拷1锟斤拷锟斤拷4锟斤拷锟斤拷锟斤拷锟絚直锟斤拷平锟叫碉拷直锟斤拷锟斤拷锟斤拷
锟斤拷锟�锟斤拷锟�2锟斤拷锟斤拷锟絕(gu锟斤拷)锟絚(di锟斤拷n)A锟斤拷1锟斤拷锟斤拷4锟斤拷锟斤拷锟斤拷锟絚直锟斤拷锟斤拷直锟斤拷直锟斤拷锟斤拷锟斤拷
锟斤拷锟斤拷20.锟斤拷锟斤拷锟絵锟組锟斤拷12锟街ｏ拷
锟斤拷锟斤拷锟斤拷锟絕(gu锟斤拷)锟絚(di锟斤拷n)A锟斤拷-3锟斤拷2锟斤拷锟侥掞拷锟斤線锟侥橈拷(bi锟斤拷o)锟斤拷(zh锟斤拷n)锟斤拷锟教★拷
锟斤拷锟斤拷21.锟斤拷锟斤拷锟絵锟組锟斤拷12锟街ｏ拷
锟斤拷锟斤拷锟絧锟斤拷锟斤拷C锟絚锟紼锟紸锟叫癸拷锟斤拷锟斤拷锟絚(di锟斤拷n)锟斤拷锟斤拷锟絰锟斤拷锟斤拷e=2.
锟斤拷锟�锟斤拷锟�1锟斤拷锟斤拷锟絧锟斤拷锟斤拷C锟侥凤拷锟教ｏ拷
锟斤拷锟�锟斤拷锟�2锟斤拷直锟斤拷锟絚锟絧锟斤拷锟斤拷C锟洁交锟斤拷A锟斤拷B锟斤拷锟絚(di锟斤拷n)锟斤拷锟斤拷|AB|锟斤拷锟斤拷锟絃(zh锟斤拷ng)锟斤拷.
锟斤拷锟斤拷22.锟斤拷锟斤拷锟絵锟組锟斤拷14锟街ｏ拷锟斤拷D锟斤拷锟絕(gu锟斤拷)锟斤拷锟斤線y2=2px(p>0)锟斤拷一锟斤拷锟絚(di锟斤拷n)P(x0,y0)(y0>0)锟斤拷锟斤拷锟缴條直锟斤拷锟街別锟斤拷锟斤拷锟斤線锟斤拷A(x1,y1)锟斤拷B(x2,y2).
锟斤拷锟斤拷锟斤拷I锟斤拷锟斤拷該锟斤拷锟斤線锟较縱锟斤拷锟斤拷(bi锟斤拷o)锟斤拷锟斤拷c(di锟斤拷n)锟斤拷锟戒焦锟絚(di锟斤拷n)F锟侥撅拷锟絰锟斤拷
锟斤拷锟斤拷锟斤拷II锟斤拷锟斤拷(d锟斤拷ng)PA锟絚PB锟斤拷斜锟绞达拷锟斤拷锟揭傾斜锟角伙拷锟絘(b锟斤拷)锟絩(sh锟斤拷)锟斤拷锟斤拷锟街碉拷锟斤拷锟斤拷C锟斤拷直锟斤拷AB锟斤拷斜锟斤拷锟角凤拷锟姐常锟斤拷(sh锟斤拷)锟斤拷
锟斤拷锟斤拷锟斤拷
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锟斤拷锟斤拷锟絵號(h锟斤拷o)123456789101112
锟斤拷锟斤拷锟絰锟�(xi锟斤拷ng)DADBDDDCCCCA
锟斤拷锟斤拷锟节拷锟斤拷锟斤拷锟斤拷x锟斤拷锟絵锟斤拷90锟街ｏ拷
锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷}
锟斤拷锟斤拷13.12锟斤拷14锟斤拷(x-2)2+y2=1015.416
锟斤拷锟斤拷17锟解不锟斤拷式
锟斤拷锟斤拷19锟斤拷1锟斤拷锟解：锟竭碉拷斜锟绞烇拷
锟斤拷锟斤拷∴锟斤拷锟斤拷直锟斤拷锟斤拷锟教為：
锟斤拷锟斤拷锟斤拷
锟斤拷锟斤拷锟斤拷2锟斤拷锟解：锟竭碉拷斜锟绞烇拷
锟斤拷锟斤拷∴锟斤拷锟斤拷直锟斤拷锟斤拷锟教為：
锟斤拷锟斤拷锟斤拷
锟斤拷锟斤拷20锟解：锟斤拷(d锟斤拷ng)锟斤拷锟斤線锟侥斤拷锟絚(di锟斤拷n)锟斤拷y锟絊锟斤拷锟斤拷锟斤拷锟絊锟较時(sh锟斤拷)锟斤拷
锟斤拷锟斤拷锟斤拷A锟斤拷-3锟斤拷2锟斤拷锟斤拷锟斤拷x2=2py锟斤拷锟斤拷p=
锟斤拷锟斤拷锟斤拷(d锟斤拷ng)锟斤拷锟絚(di锟斤拷n)锟斤拷x锟絊锟斤拷負(f锟斤拷)锟斤拷锟絊锟较時(sh锟斤拷)锟斤拷锟斤拷A锟斤拷-3锟斤拷2锟斤拷锟斤拷锟斤拷
锟斤拷锟斤拷锟斤拷p=∴锟斤拷锟斤線锟侥橈拷(bi锟斤拷o)锟斤拷(zh锟斤拷n)锟斤拷锟教烇拷
锟斤拷锟斤拷21锟斤拷锟斤拷:(1)锟斤拷锟斤拷知锟斤拷
锟斤拷锟斤拷锟紼锟紸锟斤拷锟教烇拷∴
锟斤拷锟�锟斤拷锟�2锟斤拷锟斤拷3x2-y2+1
锟斤拷锟斤拷x-y+1=0
锟斤拷锟斤拷锟斤拷x2-x-1=0
锟斤拷锟斤拷∴x1+x2=1锟斤拷x1x2=-1
锟斤拷锟斤拷|AB|=
锟斤拷锟斤拷22锟解：锟斤拷I锟斤拷锟斤拷(d锟斤拷ng)y=锟絩(sh锟斤拷)锟斤拷x=锟斤拷锟街掞拷锟斤線y2=2px
锟斤拷锟斤拷锟侥滐拷(zh锟斤拷n)锟斤拷锟斤拷锟教烇拷x=锟斤拷锟斤拷锟缴掞拷锟斤線锟斤拷锟絰锟斤拷锟斤拷锟斤拷锟斤拷
锟斤拷锟斤拷锟斤拷锟絰锟斤拷.
锟斤拷锟�锟斤拷锟絀I锟斤拷锟絆(sh锟斤拷)直锟斤拷PA锟斤拷斜锟绞烇拷kPA锟斤拷直锟斤拷PB锟斤拷斜锟绞烇拷kPB.
锟斤拷锟斤拷锟斤拷=2px1锟斤拷=2px0锟斤拷锟絧锟斤拷
锟斤拷锟�锟斤拷锟統1锟斤拷y0锟斤拷(y1+y0)=2p(x1锟斤拷x0)
锟斤拷锟斤拷锟斤拷kPA=锟斤拷x1≠x0锟斤拷同锟斤拷锟缴碉拷kPB=锟斤拷x2≠x0锟斤拷锟斤拷PA锟斤拷PB
锟斤拷锟斤拷锟紸斜锟角伙拷锟絘(b锟斤拷)知kPA=锟斤拷kPB锟斤拷锟斤拷=锟斤拷
锟斤拷锟斤拷锟斤拷锟斤拷y1+y2=锟斤拷2y0锟斤拷锟斤拷
锟斤拷锟斤拷锟絆(sh锟斤拷)直锟斤拷AB锟斤拷斜锟绞烇拷kAB.锟斤拷=2px2锟斤拷=2px1锟斤拷锟絧锟矫ｏ拷y2锟斤拷y1锟斤拷(y2+y1)=2p(x2锟斤拷x1)锟斤拷
锟斤拷锟斤拷锟斤拷锟斤拷kAB=锟斤拷x1≠x2锟斤拷锟斤拷y1+y2=锟斤拷2y0(y0>0)锟斤拷锟斤拷锟絢AB=
锟斤拷锟斤拷=锟斤拷锟斤拷锟斤拷锟斤拷kAB锟角凤拷锟姐常锟斤拷(sh锟斤拷).
