如果虚数z满足z^3=8,那么z^3+z^2+2z+1=?
问题描述:
如果虚数z满足z^3=8,那么z^3+z^2+2z+1=?
答
∵z³=8∴|z|=2∴z1=2;z2=-1+根号3i;z3=-1-根号3i z1=2:z³+z²+2z+1=8+4+4+1=17; z2=-1+i√3:z³+z²+2z+1=8+(z+1)²=8-3=5z3=-1-i√3: z³+z²+2z+1...