a) 

`A(-2) = (-2)^3-3(-2)^2+4(-2)-2023`

`= -8-3.4-8-2023`

`= -8-12-8-2023`

`= -2051`

`B(3) = 2.3^3+4.3^2-6.3+2024`

`= 2.27+4.9-18+2024`

`= 54+36-18+2024`

`= 2096`

b) 

`M(x) = A(x)+B(x)`

`= (x^3-3x^2+4x-2023)+(2x^3+4x^2-6x+2024)`

`= x^3-3x^2+4x-2023+2x^3+4x^2-6x+2024`

`= 3x^3+x^2-2x+1`

`N(x) = A(x)-B(x)`

`= (x^3-3x^2+4x-2023)-(2x^3+4x^2-6x+2024)`

`= x^3-3x^2+4x-2023-2x^3-4x^2+6x-2024`

`= -x^3-7x^2+10x-4047`

c)

`M(x) = -3x^3-x^2=2024`

thay `M(x) = 3x^3+x^2-2x+1`

`(3x^3+x^2-2x+1)-3x^3-x^2=2024`

`=> -2x+1=2024`

`=> -2x=2023`

`=> x=-1011,5`