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如图,已知△ABC,过点A作外接圆的切线交BC延长线于点P,PCPA=22,点D在AC上,且ADCD=12,延长PD交AB于点E,则AEBE的值是(

题目详情
如图,已知△ABC,过点A作外接圆的切线交BC延长线于点P,
PC
PA
=
2
2
,点D在AC上,且
AD
CD
=
1
2
,延长PD交AB于点E,则
AE
BE
的值是(  )
A.
1
4
B.
2
4
C.
1
2
D.
2
2
▼优质解答
答案和解析


如图,∵∠APC=∠BPA,∠PAC=∠B,
∴△PAC ∽ △PBA.
PC
PA
=
2
2

S △PAC
S △PBA
=
PC 2
PA 2
=
1
2

又∵
AD
CD
=
1
2

S △PAC
S △PBA
=
3 S △PAD
3
2
S △PBD
=2×
S △PAD
S △PBD
=2×
AE
BE

于是,2×
AE
BE
=
1
2
AE
BE
=
1
4

故选A.