3.6 求下列差分方程所描述的LTI离散系统的零输入响应、零状态响应和全响应。-|||-(1) (k)-2y(k-1)=f(k),-|||-f(k)=2g(k),y(-1)=-1-|||-(2) (k)+2y(k-1)=f(k),-|||-(k)=(2)^kg(k),y(-1)=1-|||-(3) (k)+2y(k-1)=f(k),-|||-f(k)=(3k+4)g(k),y(-1)=-1-|||-(4) (k)+3y(k-1)+2y(k-2)=f(k),-|||-(k)=g(k),y(-1)=1, y(-2)=0-|||-(5) (k)+2y(k-1)+y(k-2)=f(k),-|||-(k)=3((dfrac {1)(2))}^kg(k), (-1)=3, y(-2)=-5