2х^2-5х-3
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3-х

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2x^2-5x-3=0D=25-4*(-3)*2=25+24=49x1=(5+7)/2*2=12/4=3x2=(5-7)/2*2=-2/4=-0,52x^2-5x-3=2(x-3)(x+0,5)2(x-3)(x+0,5) / -(x-3) = -2(x+0,5)=-2x-1