A polynomial with integer coefficients is of the form
\[2x^4 + a_3 x^3 + a_2 x^2 + a_1 x + 18 = 0.\]
Find the number of different possible rational roots of this polynomial.
Factors of 18 = 1,2,3,6,9,18
Factors of 2 = 1, 2
All possible rational roots =
± [ 1,2,3,4,6,9,18 , 3/2 , 9/2 ]
