\(a,x^3-3x^2-x-3\)
\(=\left(x^3-x\right)-\left(3x^2+3\right)\)
\(=x^2\left(x-1\right)-3\left(x^2-1\right)\)
\(=x^2\left(x-1\right)-3\left(x-1\right)\left(x+1\right)\)
\(=\left(x-1\right)\left[x^2-3\left(x+1\right)\right]\)
\(=\left(x-1\right)\left(x^2-3x-3\right)\)
\(b,A=3+2x-x^2\)
\(-A=x^2-2x-3\)
\(-A=x^2-2\cdot x+1-4\)
\(-A=\left(x-1\right)^2-2^2\)
\(-A=\left(x-1-2\right)\left(x-1+2\right)\)
\(-A=\left(x-3\right)\left(x+1\right)\)
\(A=-\left(x-3\right)\left(x+1\right)\)
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c) 2x2(x +1) + 4x(x +1); d) 2 x(y - 1) - 2
