What are the rational routes of 8x^3+2x^2-5x+1=0 ?

By using synthetic division we can write:
8x^3+2x^2-5x+1=(x+1)(8x^2-6x+1)
then by the quadratic equation, factoring, or some other method we get
8x^3+2x^2-5x+1=(x+1)(2x-1)(4x-1)
The roots are: {-1, 1/2 1/4}