Giải bài hộ ạ !!!!!!!!!!

`3x(2x^2-5x+4)`

`=3x*2x^2-3x*5x+3x*4`

`=6x^3-15x^2+12x`

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`-2x^2(x^3-3x+7)`

`=-2x^2*x^3-2x^2*(-3x)-2x^2*7`

`=-2x^5+6x^3-14x^2`

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`(x+2)(x-5)`

`=x(x-5)+2(x-5)`

`=x^2-5x+2x-10`

`=x^2-3x-10`

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`(3x-1)(2x+3)`

`=3x(2x+3)-(2x+3)`

`=6x^2+9x-2x-3`

`=6x^2+7x-3`

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`(x-3)(x^2+2x-1)`

`=x(x^2+2x-1)-3(x^2+2x-1)`

`=x^3+2x^2-x-3x^2-6x+3`

`=x^3-x^2-7x+3`

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`2x^2-x+4)(3x-2)`

`=3x(2x^2-x+4)-2(2x^2-x+4)`

`=6x^3-3x^2+12x-4x^2+2x-8`

`=6x^3-7x^2+14x-8`

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`(2x-3)(x-4)+(2x+3)(5-x)`

`=(2x^2-8x-3x+12)+(10x-2x^2+15-3x)`

`=(2x^2-11x+12)+(-2x^2+7x+15)`

`=2x^2-11x+12-2x^2+7x+15`

`=-4x+27`

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`(2x-3)(3x-4)-(2x+3)(3x-2)`

`=(6x^2-8x-9x+12)-(6x^2-4x+9x-6)`

`=(6x^2-17x+12)-(6x^2+5x-6)`

`=6x^2-17x+12-6x^2-5x+6`

`=-22x+18`

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`(-2x-3)(3x-4)-(-2x+3)(3x-2)`

`=-(2x+3)(3x-4)+(2x-3)(3x-2)` 

`=(2x-3)(3x-2)-(2x+3)(3x-4)`

`=(6x^2-4x-9x+6)-(6x^2-8x+9x-12)`

`=6x^2-13x+6-6x^2-x+12`

`=-14x+18`

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`(x-1)(x-2)(x-3)`

`=(x^2-2x-x+2)(x-3)`

`=(x^2-3x+2)(x-3)`

`=x(x^2-3x+2)-3(x^2-3x+2)`

`=x^3-3x^2+2x-3x^2+9x-6`

`=x^3-6x^2+11x-6`