虚数z满足z^3+z=0 则1+z+z^2+…+z^100=

问题描述:

虚数z满足z^3+z=0 则1+z+z^2+…+z^100=

z(z^2+1)=0因为z是虚数,所以z≠0,于是z^2+1=0所以,z=±i于是,1+z+z^2+z^3=0所以,1+z+z^2+…+z^100=(1+z+z^2+z^3)+(z^4+z^5+z^6+z^7)+……+(z^96+z^97+z^98+z^99)+z^100=0+0+……+0+z^100=1...