题目

求卷积s(t)=sin(t)u(t)*u(t-1)

提问时间：2020-11-25

答案

s(t)=sin(t)u(t)*u(t-1)
=∫(-∞→+∞)sin(x)u(x)u(t-1-x)dx
=∫(-∞→+∞)sin(x)u(x)u(t-1-x)dx
=∫(0→t-1)sin(x)dx (t>1)
=-cos(t-1)+1 (t>1)
t≤0时,s(t)=0