How do you find the zeroes of a discrete function?

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Finding the zeroes of the function y = 40sin(2x) - floor(40sin(2x) involves identifying when 40sin(2x) is an integer, as this is when the function equals zero. The discussion suggests that Newton's method could be applicable, particularly through an iterated approach that segments the function into linear parts. While the distribution of integers from the sine function appears random, breaking the problem into manageable segments aids in finding solutions. The problem arose in a non-class context, prompting exploration of techniques to create a continuous analog from a discrete function. Ultimately, the use of Newton's method, adapted for this specific function, proves effective.
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Would Newton's method or some other method work? Consider the following problem:

find the zeroes of the function: y = 40sin(2x) - floor(40sin(2x))

where Y,X \in R

I don't exactly know how to handle this problem. My best insight so far is that it is only equal to zero whenever 40sin(2x) is an integer. But even then the distribution of these integers is quite random and I honestly don't know any inverse-floor function.
 
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Frogeyedpeas said:
Would Newton's method or some other method work? Consider the following problem:

find the zeroes of the function: y = 40sin(2x) - floor(40sin(2x))

where Y,X \in R

I don't exactly know how to handle this problem. My best insight so far is that it is only equal to zero whenever 40sin(2x) is an integer. But even then the distribution of these integers is quite random and I honestly don't know any inverse-floor function.
Could you tell us a little more about what class this is from, and what kind of similar problems you may have encountered, and tell us a little about the techniques you're class us covering?
 
ehhh not exactly from a class (sorry), and I don't have any sample problems for this thing either. It just kind of came up. My best guess is to use Newton's formula.

I mean Newton's method
 
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So this problem i basically the same thing as frac{40sin(2x)} = 0.
 
w8 nvm I'm good, I got the method
 
So what was the method? Where did the problem come up?
 
Well it turns out if you do an iterated Newton method the number works. To speed things up i broke up the function into separate segments defined as linear. The function appeared out of the context of being given a discrete function how do you make a contonuous analog
 

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