Tìm h ( n ) của hệ thống được mô tả bởi phương trình sai phân sau: y ( n ) − 4 y ( n − 2 ) = x ( n ) + 4 x ( n − 1 )

$h\left(n\right)=\left(2{}^n-3\cdot 2{}^{-n}\right)\cdot U\left(n\right)$

$\text{h}\left(\text{n}\right)=\left(3.2{}^{\text{n}}+2{}^{-\text{n}}\right)\cdot \text{U}\left(\text{n}\right)$

$h(n=\left(2{}^{-n}-3.2{}^n\right)\cdot U\left(n\right)$

$\text{h}\left(\text{n}\right)=\left(3.2{}^{\text{n}}-2{}^{-\text{n}}\right)\cdot \text{U}\left(\text{n}\right)$