Lim(2x² - 7x -4)/(-2x² +5x +3) =Lim2(x+1/2)(x-4)/(2)*(x+1/2)(x-3) = -Lim(x-4)/x-3)=
= (-1/2-4)(-1/2_3) =9/7 ;
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Lim(5x² 4x+8) = 5*(-5)² - 4*(-5) + 8= 153
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Lim(2x²+7x -1)/(3x³ - 5x) =Lim(2 +7/x - 1/x²)/(3 - 5/x) = 2/3