Lim┬(x→0)〖(1+x-x^2)/(〖2x〗^2+5x+4)〗 = =lim┬(x→0)〖(1+x-x^2):x^2/(〖2x〗^2+5x+4):x^2〗= =lim┬(x→0)〖(1/x^2+x/x^2-x^2/x^2)/(4x^2/x^2+5x/x^2+4/x^2)〗= = lim┬(x→0))〖(1/x^2+1/x-1)/(4+5/x+4/x^2)〗=-1/4