AP与BD相交于点E
作CF∥AP交BD于F
可得BE=EF=FD
BD^2=AB^2+AD^2=9
BD=3
则DE=2/3BD=2
AP^2=AB^2+(AD/2)^2=3+3/2=9/2
(2/3AP)^2+(2/3BD)^2=4/9*(9/2+9)=6=AD^2
则△AED是直角三角形
∴AE⊥ED
即AP⊥PD
AP与BD相交于点E
作CF∥AP交BD于F
可得BE=EF=FD
BD^2=AB^2+AD^2=9
BD=3
则DE=2/3BD=2
AP^2=AB^2+(AD/2)^2=3+3/2=9/2
(2/3AP)^2+(2/3BD)^2=4/9*(9/2+9)=6=AD^2
则△AED是直角三角形
∴AE⊥ED
即AP⊥PD