limx→0 ((1+x∧(1/x))/e)∧(1/x)
1个回答

limx→0 ((1+x)∧(1/x))/e)∧(1/x)

=limx→0 e^{1/x*ln[(1+x)^(1/x)/e]}

=e^ limx→0 1/x*{1/x*ln(1+x)-1]}

=e^ limx→0 {[ln(1+x)]/x-1}/x (0/0型用罗比达法则)

=e^ limx→0 {[1/(1+x)*x-ln(1+x)]/x^2}/1

=e^ limx→0 [1-1/(1+x)-ln(1+x)]/x^2 (0/0型用罗比达法则)

=e^ limx→0 [1/(1+x)^2-1/(1+x)]/(2x)

=e^ limx→0 [-1/2*1/(1+x)^2]

=e^(-1/2)

limx→0+ (sin3x)∧(1/(1+3lnx))

=limx→0+ e^[(1/(1+3lnx)*ln(sin3x)]

=e^ limx→0+ [ln(sin3x)]/(1+3lnx) (∞/∞型用罗比达法则)

=e^ limx→0+ [1/(sin3x)*3cos3x]/(3/x)

=e^ limx→0+ cos3x/3*3x/sin3x (3x~sin3x等价无穷小)

=e^(1/3)