Question 86308
Any rational zero has, as its numerator, a factor of the constant term, in this case 1, and, as its denominator, a factor of the lead coefficient, in this case 15. So the possible rational roots are: 1/1 [or just 1] , -1/1 [or just -1] , 1/3 , -1/3 , 1/5 , -1/5 , 1/15 and -1/15.