设z=y/x,而x=e^t,y=1-e^(-2t),求dz/dt?
问题描述:
设z=y/x,而x=e^t,y=1-e^(-2t),求dz/dt?
$(acontent)
答
z =y/x
= (1-e^(-2t)) /e^t
= e^(-t)-e^(-3t)
dz/dt= -e^(-t)+3e^(-3t)