# Homework Help: Natural Log and Exponential

1. Mar 6, 2010

### CursedAntagonis

1. The problem statement, all variables and given/known data
Trying to solve for K:

ln(1-4k)=-6k

2. Relevant equations

3. The attempt at a solution
I know that need to take the e of both side, to get 1-4k=e^-6k, but I cannot remember any properties of e to allow me to remove the k from the exponent. Any tips is appreciated.

2. Mar 6, 2010

### Sweet_GirL

Clearly, $$k=0$$ is a solution.
to find the another solution you need to use an advanced topic:
http://mathworld.wolfram.com/LambertW-Function.html

3. Mar 6, 2010

4. Mar 6, 2010

### vela

Staff Emeritus
You have to solve it numerically. You can't solve for k algebraically.

You can visualize the solutions by plotting the functions y=1-4k and y=e^-6k and seeing where they intersect.

5. Mar 6, 2010

### Sweet_GirL

m/s??

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook