Finding the value of n in nlog(n)

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To solve the inequality c1*n^2 < c2*n*log(n) or the equation nlog(n) = k, one cannot find an exact analytic solution. Instead, graphical methods can be employed to estimate values of n by plotting the functions involved. The Lambert W function provides a way to approach an analytic solution for equations involving nlog(n). This function is useful for expressing solutions in terms of known constants. Understanding these methods is crucial for tackling complexity questions in computational contexts.
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Homework Statement



Pretty simply, if you have an inequality like c1*n^2<c2*n*log(n), how do you find the values of n for this without plugging in diifferent values and substituting? Or a question like nlog(n)=k where k is a constant.

Homework Equations


Umm...thats it.


The Attempt at a Solution


I just plugged in solutions or thought I'd use MATLAB or something. This isn't actually my homework, but it comes up a lot in complexity questions, and I need to know hot to solve it.
 
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There is no analytic way to solve the above question. But you could ballpark the answer by drawing graphs. nlog(n) = k => log(n) = 1/n. Draw both graphs and find out the answer.

Or you could solve this problem using the Lambert W function, which is about as close you can get to an analytic solution.

http://en.wikipedia.org/wiki/Lambert_W_function
 
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