Answer:
As one of the zeros of polynomial is 0, then (x-0) =x is a factor of given polynomial. 
 
Since x is a factor , d= 0 
 
ax^3+bx^2+cx+d = ax^3+bx^2+cx 
 
= x(ax^2+bx+c) 
 
Other two roots are roots of 
 
ax^2+bx+c = 0 
 
For a quadratic equation ax^2+bx+c = 0 
 
Product of roots = c/a 
 
Sum of roots = -b/a 
 
So 
 
Product of other two roots = c/a
Hope this helps :D