# Math Help - HELP!!! derivative!

1. ## HELP!!! derivative!

How do I find the derivative of
y = ln(x) - 1
ln^2(x)

?? i tried so many ways... it never turns out right. according to the calculator anyway.

thanks in advance!

2. whats the ln^2 (x)

is it
ln(x^2)
or
(ln(x))^2

review ur log properties this ones pretty easy

3. Originally Posted by canonind
How do I find the derivative of
y = ln(x) - 1
ln^2(x)

?? i tried so many ways... it never turns out right. according to the calculator anyway.

thanks in advance!
$y = (\ln(x) - 1) \cdot \frac{1}{(\ln(x))^2}$

$\frac{dy}{dx} = \frac{1}{x} \cdot (ln(x))^{-2} + \frac{-2(ln(x))^{-3}}{x} \cdot (ln(x)-1)$

Using the product rule.
Then Simplify to:

$\frac{dy}{dx} = \frac{1}{x(ln(x))^2}\{\frac{2}{ln(x)} - 1 \}$

Understand?