历忠毛子种技大字 XI UNIVERSITY r(t) (f) r(t)=Asin O t=0 6(1)=r(t) 0t≠0 (t)d=1 r(s)=L[r() LLAsin(at ) r(s)=L[r(tl A/(s2+ =LD()]         0 0 0 ( ) ( ) t t  t r t ( ) 1     t dt ( ) [ ( )] [ ( )] 1 r s L r t L t     r(t)  Asint 2 2 ( ) [ ( )] [ sin( )] / ( ) r s L r t L A t A s       