What is the derivative of Ln(ln(ln(2x)))?

1 Answer
Sep 5, 2016

1/(( ln (ln (2x)))(ln (2x)(x)), x>e/2

Explanation:

For real logarithms:

ln (2x) is real, for x> 0#

ln ( ln (2x)) is real, for ln (2x) > 0, So, ln (2x) > 0. And so, x > 1/2.

ln (ln (ln (2x))) is real, for ln(ln(2x))> 0. So,

ln (ln (2x)) >0 to ln (2x) > 1 to 2x > e to x > e/2.

All are real, for x > e/2.

In succession, apply function rule.

(ln(ln(ln(2x))))'

=1/(ln(ln(2x)))(ln(ln(2x))'

=1/((ln(ln(2x)))(ln(ln(2x)) (ln(2x))'

=1/((ln(ln(2x)))(ln(ln(2x))) 1/(2x)(2x)'

=1/((ln(ln(2x)))(ln(2x)(x)), x>e/2
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