已知x=1+根号3,那么1/x+2+1/x^2-4+1/x-2=

问题描述:

已知x=1+根号3,那么1/x+2+1/x^2-4+1/x-2=

就你表面的式子来看,=2/x+1/x^2-4=根号3-1-4+1-根号3/2=根号3/2-4
但是如果是求1/(x+2)+1/(x^2-4)+1/(x-2)=(2x+1 )/(x^2-4)=1+根号3/2

1/(x+2)+1/(x^2-4)+1/(x-2)=(2x+1 )/(x^2-4)=1+根号3/2