1/(2根号1+1根号2)=(2根号1-1根号2)/(4-2)=根号1-(根号2)/21/(3根号2+2根号3)=(3根号2-2根号3)/(18-12)=(根号2)/2-(根号3)/31/(2根号1+1根号2)+1/(3根号2+2根号3)+.+1/(100根号99+99根号100) =根号1-(根号)/2+(根号)...