lim(x→0) ln[(3-e^x)/(2+x)]^(1/sinx)
=lim(x→0) ln[(3-e^x)/(2+x)]/sinx
=lim(x→0) [ln(3-e^x)-ln(2+x)]/sinx
=lim(x→0) [ln(3-e^x)-ln(2+x)]/x (0/0)
=lim(x→0) -e^x/(3-e^x)-1/(2+x)
=-1
所以
lim(x→0) [(3-e^x)/(2+x)]^(1/sinx)
=lim(x→0) e^ln[(3-e^x)/(2+x)]^(1/sinx)
=e^(-1)
=1/e