Problem 837. Find all the zeros of sinus , cosinus and tangent in a given interval

Created by Aurelien Queffurust

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Last Solution submitted on Sep 04, 2020

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Tim on 17 Jul 2012

I think test case 2 might be incorrect.

Richard Zapor on 17 Jul 2012

I disagree slightly with the expected solution to test 2.
Test 2 cos between [0 2pi]
[-pi/2 pi/2 3*pi/2]

I do not believe that -pi/2 is in the interval [0 2*pi].

If -pi/2 is desired then the answer to sin [0 2*pi] should be [-2*pi -pi 0 pi 2*pi]

Richard Zapor on 17 Jul 2012

Correction of assert function.
One of the ")" is in the wrong place.
is:
assert(all(abs(find_zeros(@sin,0,2*pi) -[0 pi 2*pi]<1e-9)))

Should be:
assert(all(abs(find_zeros(@sin,0,2*pi) -[0 pi 2*pi])<1e-9))

Rafael S.T. Vieira on 4 Sep 2020 at 17:24

As mentioned by others, the 2nd test case is incorrect, -pi/2 is outside the interal [0,2*pi] for the function cosine. And if we do plot cos(x) on said interval, we notice that the cosine function crosses the x-axis only twice.

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Solution 114999

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Cris Luengo on 18 Jul 2012

Yeah, the test set is wrong...

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circle cos sin tan trigonometry zeros

Problem 837. Find all the zeros of sinus , cosinus and tangent in a given interval

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Problem 837. Find all the zeros of sinus , cosinus and tangent in a given interval

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