Root: Difference between revisions

From Xenharmonic Wiki
Jump to navigation Jump to search
Wikispaces>xenjacob
**Imported revision 36370601 - Original comment: **
 
Wikispaces>FREEZE
No edit summary
Line 1: Line 1:
<h2>IMPORTED REVISION FROM WIKISPACES</h2>
The arithmetical concept of ''[http://en.wikipedia.org/wiki/Nth_root roots]'' is often encountered in discussions about tuning.
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
: This revision was by author [[User:xenjacob|xenjacob]] and made on <tt>2008-08-29 00:20:05 UTC</tt>.<br>
: The original revision id was <tt>36370601</tt>.<br>
: The revision comment was: <tt></tt><br>
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
<h4>Original Wikitext content:</h4>
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;white-space: pre-wrap ! important" class="old-revision-html"> The arithmetical concept of //[[http://en.wikipedia.org/wiki/Nth_root|roots]]// is often encountered in discussions about tuning.


==How are roots related to equal divisions?==
==How are roots related to equal divisions?==


To divide an interval //a// into //b// equal parts, that is, to calculate the size of the interval that, when repeated //b// times, would add up to //a//, calculate the //bth root of a//.  The equivalent expression is to take //a// to the //(1/b)th power//.
To divide an interval ''a'' into ''b'' equal parts, that is, to calculate the size of the interval that, when repeated ''b'' times, would add up to ''a'', calculate the ''bth root of a''.  The equivalent expression is to take ''a'' to the ''(1/b)th power''.


Why roots and powers?  Because intervals are proportions, which you must multiply in order to "add".
Why roots and powers?  Because intervals are proportions, which you must multiply in order to "add".
Line 18: Line 11:
It isn't once...because two onces is just another once!
It isn't once...because two onces is just another once!


It's the square //root// of 2!  Try it:  The √2 *multiplied* twice is √2*√2 = 2.  (Note that √2 *added* twice would be 2√2.)
It's the square ''root'' of 2!  Try it:  The √2 *multiplied* twice is √2*√2 = 2.  (Note that √2 *added* twice would be 2√2.)
</pre></div>
[[Category:concept]]
<h4>Original HTML content:</h4>
[[Category:math]]
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;width:200%;white-space: pre-wrap ! important" class="old-revision-html">&lt;html&gt;&lt;head&gt;&lt;title&gt;roots&lt;/title&gt;&lt;/head&gt;&lt;body&gt; The arithmetical concept of &lt;em&gt;&lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Nth_root" rel="nofollow"&gt;roots&lt;/a&gt;&lt;/em&gt; is often encountered in discussions about tuning.&lt;br /&gt;
[[Category:root]]
&lt;br /&gt;
[[Category:tuning]]
&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc0"&gt;&lt;a name="x-How are roots related to equal divisions?"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt;How are roots related to equal divisions?&lt;/h2&gt;
&lt;br /&gt;
To divide an interval &lt;em&gt;a&lt;/em&gt; into &lt;em&gt;b&lt;/em&gt; equal parts, that is, to calculate the size of the interval that, when repeated &lt;em&gt;b&lt;/em&gt; times, would add up to &lt;em&gt;a&lt;/em&gt;, calculate the &lt;em&gt;bth root of a&lt;/em&gt;.  The equivalent expression is to take &lt;em&gt;a&lt;/em&gt; to the &lt;em&gt;(1/b)th power&lt;/em&gt;.&lt;br /&gt;
&lt;br /&gt;
Why roots and powers?  Because intervals are proportions, which you must multiply in order to &amp;quot;add&amp;quot;.&lt;br /&gt;
&lt;br /&gt;
Take a simple example: what's half of an octave?  Well, an octave means &amp;quot;twice the frequency&amp;quot; or &amp;quot;2 times whatever you have&amp;quot; or &amp;quot;2 to 1&amp;quot; or simply &amp;quot;2&amp;quot;.  (The 2 itself has no units, because they cancel out:  to calculate that octave between A-220 and A-440, we divide 440 Hertz by 220 Hertz and get... plain ol' 2.)  If an octave means &amp;quot;twice&amp;quot;, then what's half of &amp;quot;twice&amp;quot;? &lt;br /&gt;
&lt;br /&gt;
It isn't once...because two onces is just another once!&lt;br /&gt;
&lt;br /&gt;
It's the square &lt;em&gt;root&lt;/em&gt; of 2!  Try it:  The √2 *multiplied* twice is √2*√2 = 2.  (Note that √2 *added* twice would be 2√2.)&lt;/body&gt;&lt;/html&gt;</pre></div>

Revision as of 00:00, 17 July 2018

The arithmetical concept of roots is often encountered in discussions about tuning.

How are roots related to equal divisions?

To divide an interval a into b equal parts, that is, to calculate the size of the interval that, when repeated b times, would add up to a, calculate the bth root of a. The equivalent expression is to take a to the (1/b)th power.

Why roots and powers? Because intervals are proportions, which you must multiply in order to "add".

Take a simple example: what's half of an octave? Well, an octave means "twice the frequency" or "2 times whatever you have" or "2 to 1" or simply "2". (The 2 itself has no units, because they cancel out: to calculate that octave between A-220 and A-440, we divide 440 Hertz by 220 Hertz and get... plain ol' 2.) If an octave means "twice", then what's half of "twice"?

It isn't once...because two onces is just another once!

It's the square root of 2! Try it: The √2 *multiplied* twice is √2*√2 = 2. (Note that √2 *added* twice would be 2√2.)