数字信号 已知F(S)=12(S+8)/S(S+4)(S+12),求原函数f(t)

设F(s)=A/s+B/(s+4)+C/(s+12)则：A=sF(s)|s=0=12(0+8)/(0+4)(0+12)=2B=(s+4)F(s)|s=-4=12(-4+8)/(-4)(-4+12)=-3/2C=(s+12)F(s)|s=-12=12(-12+8)/(-12)(-12+4)=-1/2即：F(s)=2/s-3/2(s+4)-1/2(s+12)所以：f(t)=2u(t)-...