chord AB of parabola Y2=4aX cut an axis of parabola at C. If A=(at12,2at1) and B=(at22,2at2) and AC:AB=1:3. then?...............(A)t2=2t1(B)t2+2t1=0(C)t1+2t2=0(D)t1+t2=0

Dear Student,
If AC:AB = 1:3,
then C divides AB in the radio 1:2.
Since axis is the x-axis, therfore, the coordinat of C will be zero. Now just apply the section formula only for the y-coordinate and you will get your answer.
Thanks,

Approved