酉空间的性质: (1)(a,kB)=k(a,B) (2)(a,B+y)=(a,B)+(a,y) (3)∑ka,B)=∑k(a,B) a∑kB)=∑(a,)酉空间的性质： 1 1 1 1 (1) ( , ) ( , ) (2) ( , ) ( , ) ( , ) (3) ( , ) ( , ) (4) ( , ) ( , ) t t i i i i i i t t i i i i i i k k k k k k                    = = = = = + = + = =    