Question

lim(x3+1/x2+1)-ax-b=1,x趋向无穷,求常数a,b

Answer 1

(x^3+1)/(x^2+1)-ax-b

=(x^3+1-ax^3-bx^2-ax-b)/(x^2+1)

=[(1-a)x^3-bx^2-ax-b+1)/(x^2+1)

根据题意得

1-a=0

-b=1

∴a=1

b=-1