a) \(\left(x-1\right)^2-2\left(x-3\right)\left(x-1\right)+\left(x-3\right)^2\)
\(=\left[\left(x-1\right)-\left(x-3\right)\right]^2\)
\(=\left(x-1-x+3\right)^2\)
\(=2^2\)
\(=4\)
Vậy: ...
b) \(\left(x-1\right)^3-\left(x+2\right)\left(x^2-2x+4\right)+3x^2-3x\)
\(=x^3-3x^2+3x-1-\left(x^3+8\right)+3x^2-3x\)
\(=\left(x^3-x^3\right)-\left(3x^2-3x^2\right)+\left(3x-3x\right)-\left(1+8\right)\)
\(=-9\)
Vậy: ...
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