\(A\left(x\right)=6x^3-x\left(x+2\right)+4\left(x+3\right)\)
\(A\left(x\right)=6x^3-x^2+2x+4x+12\)
\(A\left(x\right)=6x^3-x^2+\left(2x+4x\right)+12\)
\(A\left(x\right)=6x^3-x^2+6x+12\)
\(B\left(x\right)=-x\left(x+1\right)-\left(4-3x\right)+x^2\left(x-2\right)\)
\(B\left(x\right)=-\left(x^2\right)+2-4+3x+x^3-2x^2\)
\(B\left(x\right)=\left(-x^2-2x^2\right)+\left(2-4\right)+3x+x^3\)
\(B\left(x\right)=-3x^2-2+3x+x^3\)
Sửa lại cho Bạn Vũ Đình Phước nhé :v
A (x) = 6x3 – x (x + 2) + 4 (x + 3)
= 6x3 – x2 - 2x + 4x + 12
= 6x3 – x2 + 2x + 12