A logarithm #log_a(x)# is the value fulfilling the equation #a^(log_a(x))=x#.
#ln# represents the natural logarithm, that is, the logarithm with base #e#. To solve, then, we can isolate #ln(x)# and then apply the exponential function. As #ln(x)# is the same as #log_e(x)#, then #e^ln(x) = x#.
#ln(x) - 2 = 0#
#=>ln(x) = 2#
#=>e^(ln(x))= e^2#
#=> x = e^2#