4x(3x² - x) - (2x +3)(6x² - 3x +1)
= 12x³ - 4x² - (12x³ - 6x² +2x + 18x² - 9x +3)
= 12x³ - 4x² - 12x³ + 6x² - 2x - 18x² + 9x - 3
= -16x² +7x - 3
\(4x\left(3x^2-x\right)-\left(2x+3\right)\left(6x^2-3x+1\right)\\ =12x^3-4x^2-12x^3+6x^2-2x-18x^2+9x-3\\ =-16x^2+7x-3\)
....................??????????????no