1.5求極限lim(x→4)(x^2-6x+8)/(x^2-5x+4) 1.5求極限lim(x→4)(x^2-6x+8)/(x^2-5x+4)

1.5求極限lim(x→4)(x^2-6x+8)/(x^2-5x+4) 1.5求極限lim(x→4)(x^2-6x+8)/(x^2-5x+4)

lim(x→4)(x^2-6x+8)/(x^2-5x+4)
=lim(x→4)(x-2)(x-4)/((x-1)(x-4))
=lim(x→4)(x-2)/(x-1)
=(4-2)/(4-1)
=2/3