Question

a) Thực hiện phép tính:

3x(4x - 3) - (2x - 1) (6x + 5 ) 

Answer 1

\(3x\left(4x-3\right)-\left(2x-1\right)\left(6x+5\right)\\ =12x^2-9x-\left(12x^2+10x-6x-5\right)\)

\(=12x^2-9x-\left(12x^2+4x-5\right)\\ =5-13x\)

Answer 2

Answer 3

\(3x\left(4x-3\right)-\left(2x-1\right)\left(6x+5\right)\)

\(=12x^2-9x-12x^2-10x+6x+5\)

\(=-13x+5\)