Question

求下列各式的微分 如图

Answer 1

dy = d(x*e^x) = e^xdx + xd(e^x) = e^xdx + xe^xdx = (1+x)e^xdx

dy = d[x*e^(-x)] = e^(-x)dx + xd[e^(-x)] = e^(-x)dx + xe^(-x)d(-x) = e^(-x)dx - xe^(-x)dx = (1-x)e^(-x)dx