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Question

thu gọn M(x)=2x(x-3)-5(x-2)+3x2

N(x)=-x(x+1)-(3x-4)+x2(2x-3)

M(x)-N(x)-x2(x+6)

Đời về cơ bản là buồn...... · Accepted Answer

$M\left(x\right)=2x\left(x-3\right)-5\left(x-2\right)+3x^2$

$=2x^2-6x-5x+10+3x^2$

$=5x^2-11x+10$

$N\left(x\right)=-x\left(x+1\right)-\left(2x-4\right)+x^2\left(2x-3\right)$

$=-x^2-x-2x+4+2x^3-3x^2$

$=2x^3-4x^2-3x+4$

$M\left(x\right)-N\left(x\right)-x^2\left(x+6\right)$

$=5x^2-11x+10-\left(2x^3-4x^2-3x+4\right)-x^2\left(x+6\right)$

$=5x^2-11x+10-2x^3+4x^2+3x-4-x^3-6x^2$

$=-3x^3+3x^2-8x+6$Câu trả lời: $M\left(x\right)=2x\left(x-3\right)-5\left(x-2\right)+3x^2$