List all possible rational zeros of...

h(x)= 2x to the (4th power) - 5x (to the third power) + 3x (to the 2nd power) + 4x - 6

Use the Rational Roots Theorem. Any root of the form p/q with p and q relatively prime must be such that p divides 6 and q divides 2. You then find the following possible rational roots:

1/2, 1, 3/2, 2, 3, 6 and

-1/2, -1, -3/2, -2, -3, -6