a) A = 4x(3x - 2 )- 6x(x-3)
= 12x^2 - 8x - 12x^2 + 18x
= 10x
b) B = 5x(x^2 - 2x + 1 ) - x^2 (5x-2)
= 5x^3 - 10x^2 + 5x -5x^3 + 2x^2
= -8x^2 + 5x
a, 14x ( 3x - 2 ) - 6x ( x- 3 )
= 14 x 2-8x-6x 2+18 x
= 6x2+ 10 x
b , 5x ( x2-2x +1 ) - x2(5x - 2 )
= 5x 3-10x2+ 5x -5x 3+ 2x2
= -8x2+ 5x
tick đún _ g mình nha