Wikipedia:Reference desk/Archives/Mathematics/2011 October 1

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October 1[edit]

Solving cos(ax) = cos(bx) generally[edit]

Hi,

Is there a formula for solving cos(ax) = cos(bx) generally? WolframAlpha seemed to be able to come up with pretty exact results. See http://www.wolframalpha.com/input/?i=cos%289x%29%3Dcos%287x%29. 76.104.20.125 (talk) 05:09, 1 October 2011 (UTC)[reply]

The equation is equivalent to ax = 2πn ± bx. Looie496 (talk) 05:46, 1 October 2011 (UTC)[reply]
Assuming that n is an integer then the ± is redundent here because cosine is an even function, i.e. cos(x) = cos(–x) for all x. Fly by Night (talk) 17:39, 3 October 2011 (UTC)[reply]

moving an article from my priviate place to the public[edit]

i've written an article that appears when i link on the tab with my user name (ldecola) and want to make it public. — Preceding unsigned comment added by Ldecola (talkcontribs) 20:19, 1 October 2011 (UTC)[reply]

That's not hard to do, but can I suggest that you work on it a bit more before moving it to article space? At the moment all it does is state a few vague generalities, and even those are not verifiable, because the only reference given is an entire book, with no indication of where in the book those facts come from (if they come from the book at all). I fear that in its current state, somebody would be likely to nominate it for deletion -- you can avoid that by fleshing it out a bit more. Looie496 (talk) 03:38, 2 October 2011 (UTC)[reply]
You could also talk to the nice people at WP:WPM |Aacehm| 18:13, 2 October 2011 (UTC)[reply]