Limit[(x - 0.715775 i)*(b6*x^2 + b7*x + b8)/(b1*x^5 + b2*x^3 + b3*x^2 + b4*x + b5), x -> 0.715775 i]
Limit[(x - 13.9852 i)*(b6*x^2 + b7*x + b8)/(b1*x^5 + b2*x^3 + b3*x^2 + b4*x + b5), x ->13.9852 i]

有没有大佬呀