(1)设点P坐标为(t,0)
当xC=t时,yC=-t+1
当xD=t时,yD=t+2
∴CD=yD-yC=(t+2)-(-t+1)=2t+1
∵OQ=3t
∴当正方形OQAB与正方形CDEF的面积相等时,CD=OQ
∴2t+1=3t
解得t=1
(2)当点C在线段AQ上时,yQ=3t,yC=-t+1
∴3t=-t+1
解得t=?
①当0<t≤?时,S=0
②当?<t≤1时,S=[(2t+1)-(t+2-3t)](3t-2t)=8t?-2t
③当t>1时,S=(t+2)(3t-2t)=2t?+4t
(3)t有四个值,分别为?、13、3+√66、3-√66