Question #d5319

2 Answers
Dec 9, 2017

See other answer.

Dec 9, 2017

#2#

Explanation:

#lim_(x->oo) log_e(((3x+1)/(3x-2))^(2x+1)) = log_e(lim_(x->oo)((3x+1)/(3x-2))^(2x+1))#

now making the transformation

#(3x+1)/(3x-2) = 1+1/y# or #x = 1/3(3y+2)# we have

#((3x+1)/(3x-2))^(2x+1) equiv (1+1/y)^(2y+7/3) = (1+1/y)^(7/3)((1+1/y)^y)^2#

now #lim_(x->oo) log_e(((3x+1)/(3x-2))^(2x+1)) = log_e(lim_(y->oo)(1+1/y)^(7/3)lim_(y->oo)((1+1/y)^y)^2) = log_e e^2 = 2#