例:动量算符 (h h ax 2π ih f(x)=Pf(x(P=n df(x)=Idx dInf(x)=xdx 正P f(x)ih f(x)=Cexp(ixX例：动量算符 ) 2 h ( x P i ˆ x  =   = −   f(x) P f(x) (P ) x i = x x =    −  dx i P f(x) df(x) x −  = dx iP dlnf(x) x  = x) P f(x) Cexp(i x  =