`(x^2-3x+1/4)·(-3x^3)`

`=x^2·(-3x^3)-3x·(-3x^3)+1/4·(-3x^3)`

`=-3x^5+9x^4-3/4x^3`

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`0,2·(5x-3)-1/2·(2/3x+6)+2/3·(3-x)`

`=1/5·(5x-3)-1/2·(2/3x+6)+2/3·(3-x)`

`=x-3/5-1/3x-3+2-2/3x`

`=(x-1/3x-2/3x)+(-3/5-3+2)`

`=-8/5`

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`(4x-3)(2x^2-5x+6)`

`=4x(2x^2-5x+6)-3(2x^2-5x+6)`

`=8x^3-20x^2+24x-6x^2+15x-18`

`=8x^3+(-20x^2-6x^2)+(24x+15x)-18`

`=8x^3-26x^2+39x-18`

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`(7x-2)(-2x+5)`

`=7x(-2x+5)-2(-2x+5)`

`=-14x^2+35x+4x-10`

`=-14x^2+39x-10`