西安毛子科技大学二XIDIANUNIVERSITY其次,任取α,βeV,设 α=a,6,β=b6ii=1=1若 (α)=α(β),则有Za,0(6,) =b,0(6,),i=1i=1"(8)),0(2),",0(8n) 线性无关 a;=b,,i=1,2,,n,即 α=β.从而,为单射.故为双射。由(2),α 为可逆变换1 2 ( ), ( ), , ( ) n 线性无关 , 1,2, , , i i = = a b i n 若 ( ) ( ), = 则有 其次,任取 , , V 设 1 1 , , n n i i i i i i a b = = = = 1 1 ( ) ( ), n n i i i i i i a b = = = 即 = . 由(2), 为可逆变换. 从而, 为单射. 故 为双射