问答题求下列函数的傅氏变换:f(t)=sin(ω0t)u(t)
问答题若f1(t)= ,求f1(t)*f2(t)。
问答题证明下列各式:[f1(t)+f2(t)]*[g1(t)+g2(t)]=f1(t)*g1(t)+f2(t)*g1(t)+f1(t)*g2(t)+f2(t)*g2(t)
问答题证明下列各式:eat[f1(t)*f2(t)]=[eatf1(t)]*[eatf2(t)](a为常数)
问答题证明下列各式:a[f1(t)*f2(t)]=[af1(t)]*f2(t)=f1(t)*[af2(t)](a为常数)