Multiply: (3x-1)(4x^2-2x-1).

please show the steps to solve this problem

.. (3x - 1)(4x^2 - 2x - 1)
= (3x)(4x^2 - 2x - 1) - (4x^2 - 2x - 1)
= 12x^3 - 6x^2 - 3x - 4x^2 + 2x + 1
= 12x^3 - 6x^2 - 4x^2 - 3x + 2x + 1
= 12x^3 - (6 + 4) x^2 + (- 3 + 2) x + 1
= 12x^3 - 10x^2 - x + 1