Then: lny = (1/x) [ln (ax-1)-ln (a-1)-lnx]
lim[x→+∞] lny
= lim[x→+∞][ln(a^x- 1)-ln(a- 1)-lnx]/x
L'Hospital's rule
= lim[x→+∞][a^xlna/(a^x- 1)- 1/x]
= lim[x→+∞][(a^x- 1+ 1)lna/(a^x- 1)- 1/x]
= lim[x→+∞][lna+lna/(a^x- 1)- 1/x]
When a> is at 1, the limit of the above formula is lna.
When 0
Therefore, when a> is at 1, the limit value is e (lna) = a.
When 0
The beauty of mathematics team will answer your questions. If you don't understand, please ask. If you have solved the problem, please click "Select as Satisfied Answer" below.