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\(\left(3x^2-2x-3\right).\left(x^2-4x+2\right)\)
\(=3x^2.x^2+3x^2.\left(-4x\right)+3x^2.2+\left(-2x\right).x^2+\left(-2x\right).\left(-4x\right)+\left(-2x\right).2+\left(-3\right).x^2+\left(-3\right).\left(-4x\right)+\left(-3\right).2\)
\(=3x^4-12x^3+6x^2-2x^3+8x^2-4x-3x^2+12x-6\)
\(=3x^4-10x^3+17x^2+8x-6\)
\(\left(9x^2+6x+4\right).\left(3x-2\right)\)
\(=9x^2.3x+9x^2.\left(-2\right)+6x.3x+6x.\left(-2\right)+4.3x+4.\left(-2\right)\)
\(=27x^3-18x^2+18x^2-12x+12x-8\)
\(=27x^3-8\)
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