x1()=[(+11+8(-11)+(+9)+(-9) 2 1()=X1()H1(O)= [1(+11)+118(-11)+98(+9)+9(0-9 9 y1()=F[Y(a cos1lt+=cos 9t x2(t)=y,(t)cos loot 11 cos1lt cos loot +cos 9t cos loot 2 2 H2 cos a cos B=cos(a+B)+cos(a-B) 11 x,(t)=[ 1lIt +cos 89t]+-[cos 109t +cos 9It 4 4[ ( 11) ( 11) ( 9) ( 9)] 2 ( ) 1 =   + +   − +   + +   −  X  [11 ( 11) 11 ( 11) 9 ( 9) 9( 9)] 2 ( ) ( ) ( ) 1 1 1 + + − + + + − = =         Y  X  H  y t F Y t cos9t 2 9 cos11 2 11 ( ) [ ( )] 1 = = + −  t t t t x t y t t cos9 cos100 2 9 cos11 cos100 2 11 2 ( ) 1 ( ) cos100 + = = [cos109 cos91 ] 4 9 [cos111 cos89 ] 4 11 ( ) 2cos cos cos( ) cos( ) 2 x t = t + t + t + t 用   =  +  +  − 