已知M=m+m²+m³+。。m²º¹¹,若m²=1,求M的值是多?
已知M=m+m²+m³+。。m²º¹¹,若m²=1,求M的值是多少
m²=1,说明m = ± 1. 所以两种情况 1. 如果m = 1,则m = m² = m³ = ... = m²º¹¹ = 1,所以M = 1+ 1+ 1+....+1 = 2011 2. 如果m = -1, 那么奇次方都等于-1,偶次方都等于1,加在一起M = -1 + 1 + (-1) + 1 + .... + (-1) = -1