急!一个关于taylor polynomials的问题
2个回答

根据Taylor Polynomials

f(x)=f(2)+f'(2)(x-2)+f"(2)(x-2)^2/2+Pn=0+0+(3/2)(x-2)^2+Pn

=(3/2)(x-2)^2+Pn

g(x)=g(2)+g'(2)(x-2)+g"(2)(x-2)^2/2+Qn=0+22(x-2)+(5/2)(x-2)^2+Qn

=22(x-2)+(5/2)(x-2)^2+Qn

h(x)=h(2)+h'(2)(x-2)+h"(2)(x-2)^2/2+Pn=0+0+(7/2)(x-2)^2+Rn

=(7/2)(x-2)^2+Rn

其中,Pn,Qn和Rn分别是f(x),g(x)和h(x)的三阶余项

lim(x→2)f(x)/g(x)=lim(x→2)((3/2)(x-2)^2+Pn)/(22(x-2)+(5/2)(x-2)^2+Qn)

lim(x→2)f(x)/h(x)=lim(x→2)((3/2)(x-2)^2+Pn)/((7/2)(x-2)^2+Rn)

根据L'Hôpital's Rule

lim(x→2)f(x)/g(x)=0/22=0

lim(x→2)f(x)/h(x)=(3/2)/(7/2)=3/7