Question

(z-1)/(z+1) z=1幂级数展开

Answer 1

(z-1)/(z+1) = (Z-1) / [2+(Z-1)]

=[(Z-1)/2] / {1+[(Z-1)/2]}

=[(Z-1)/2] * [1-(Z-1)/2+(Z-1)^2/2^2-(Z-1)^3/2^3+.] , |Z-1|