why lim x->1 (ln|lnx|) =-∞ not +∞???

thanh loan

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when i learn math about lim, i don't understand that WHY lim x->1 (ln|lnx|) =-∞, not +∞? who can help me ?
Many thanks! :* :) :X
 
when i learn math about lim, i don't understand that WHY lim x->1 (ln|lnx|) =-∞, not +∞? who can help me ?
Many thanks! :* :) :X

Using a graphing calculator or wolframalpha.com - plot y = ln(|ln(x)|)

Then look at the behavior of the function in the vicinity of x = 1.
 
when i learn math about lim, i don't understand that WHY lim x->1 (ln|lnx|) =-∞, not +∞? who can help me ?

We use the continuity of x\displaystyle \left| x \right|.

Recall that limx1ln(x)=\displaystyle {\lim _{x \to 1}}\ln (x) = - \infty so
limx1ln(ln(x))=ln(limx1ln(x))= ?\displaystyle {\lim _{x \to 1}}\ln \left( {\left| {\ln (x)} \right|} \right) = \ln \left| {\left( {{{\lim }_{x \to 1}}\ln (x)} \right)} \right|=~?
 
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