how can i solve x/ln(n)=100

[danielhaish]

Hi i am worikng on some encryption program and i need to solve this problem thereis any chance thus is possible using w Limburg function and how

 

[Deleted member 4993]

Hi i am worikng on some encryption program and i need to solve this problem thereis any chance thus is possible using w Limburg function and how

The expression in the subject line

x/lenx=n

does not make any sense to me. Please "correct" it and re-post.

 

[danielhaish]

The expression in the subject line

x/lenx=n

does not make any sense to me. Please "correct" it and re-post.

is it ok now i just need alitle help in solving this kind of problem

 

[Deleted member 4993]

is it ok now i just need alitle help in solving this kind of problem

Sorry .... I still cannot decipher your problem statement.

 

[Harry_the_cat]

What is "len"?

 

[danielhaish]

I am sory I meant ln

 

[danielhaish]

i cant edit it right now from some reason
so this is the equation x/ln(x)=n

 

[MarkFL]

I would use the function:

[MATH]f(x)=x-n\ln(x)=0[/MATH]
And use the Newton-Raphson method to recursively find the root to a desired accuracy.

 

[danielhaish]

hi i olso got something like that but cant solve it
nt-e^t=0

I would use the function:

[MATH]f(x)=x-n\ln(x)=0[/MATH]
And use the Newton-Raphson method to recursively find the root to a desired accuracy.

in the end i simplified it to 100t-e^t while t=len(x)
and i use regula falsi method tenx

 

[HallsofIvy]

To solve \(\displaystyle \frac{x}{ln(x)}= n\) for x, write it as \(\displaystyle \frac{ln(x)}{x}= \frac{1}{n}\) and let y= 1/x. The equation becomes \(\displaystyle y ln(1/y)= -y ln(y)= \frac{1}{n}\) or \(\displaystyle y ln(y)= -\frac{1}{n}\). NOW you can use Lambert's W function that I think you intended in your first post: \(\displaystyle y= W\left(-\frac{1}{n}\right)\) and then \(\displaystyle x= \frac{1}{W\left(-\frac{1}{n}\right)}\).

 

[danielhaish]

To solve \(\displaystyle \frac{x}{ln(x)}= n\) for x, write it as \(\displaystyle \frac{ln(x)}{x}= \frac{1}{n}\) and let y= 1/x. The equation becomes \(\displaystyle y ln(1/y)= -y ln(y)= \frac{1}{n}\) or \(\displaystyle y ln(y)= -\frac{1}{n}\). NOW you can use Lambert's W function that I think you intended in your first post: \(\displaystyle y= W\left(-\frac{1}{n}\right)\) and then \(\displaystyle x= \frac{1}{W\left(-\frac{1}{n}\right)}\).

tenx it make my program alot more simple becuase now i just use function that allready exsits

 

[danielhaish]

To solve \(\displaystyle \frac{x}{ln(x)}= n\) for x, write it as \(\displaystyle \frac{ln(x)}{x}= \frac{1}{n}\) and let y= 1/x. The equation becomes \(\displaystyle y ln(1/y)= -y ln(y)= \frac{1}{n}\) or \(\displaystyle y ln(y)= -\frac{1}{n}\). NOW you can use Lambert's W function that I think you intended in your first post: \(\displaystyle y= W\left(-\frac{1}{n}\right)\) and then \(\displaystyle x= \frac{1}{W\left(-\frac{1}{n}\right)}\).

hi i tried possed n=10 and then take the x and poss it in education and it doesn't return 10 it return 4