5. \( f(t) \) 波形如【圖 5】所示，則 \( f(t) \) 函數可用下列何者來代表？(其中 \( u_s(t) \) 表示單位步階函數)
(A) \( f(t)=[u_s(t)-u_s(t-1)]+[u_s(t-4)-u_s(t-5)] \)
(B) \( f(t)=[u_s(t-1)-u_s(t)]+[u_s(t-5)-u_s(t-4)] \)
(C) \( f(t)=[u_s(t)-u_s(t+1)]+[u_s(t+4)-u_s(t+5)] \)
(D) \( f(t)=[u_s(t+1)-u_s(t)]+[u_s(t+5)-u_s(t+4)] \)

相關試題

相關試卷