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<p style="margin-top:0;margin-bottom:0">Definitions *are* <span>equivalences.</span></p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>Från:</b> MacOSX-TeX <macosx-tex-bounces@email.esm.psu.edu> för Ross Moore <ross.moore@mq.edu.au><br>
<b>Skickat:</b> den 21 augusti 2018 13:21<br>
<b>Till:</b> TeX on Mac OS X Mailing List<br>
<b>Kopia:</b> TeX on Mac OS X Mailing List<br>
<b>Ämne:</b> Re: [OS X TeX] Latex symbol for "define equal"</font>
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<div>Hi all.</div>
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<div>I agree with using "when", or better "precisely when", in definitions.</div>
<div>Do not use these words in theorems. There are many alternative ways to express what you want.</div>
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<div>But didn't this thread start out asking for a symbolic notation?</div>
<div>In that context, equivalence is *not* the word you want for a definition, as equivalence depends on a particular relation, so is weaker than a definition.</div>
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<div>There are nuances in mathematical concepts and notations that are not always correctly appreciated by those who work primarily in other (mostly applied) fields.</div>
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On 21/08/2018, at 13:03, "Markus Klyver" <<a href="mailto:markusklyver@hotmail.com" id="LPlnk774387" class="OWAAutoLink" previewremoved="true">markusklyver@hotmail.com</a>> wrote:<br>
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<p style="margin-top:0; margin-bottom:0">But how would the reader know if it's a theorem or a definition? Consider the statement "f(x)=1 when x=2". Do we mean f(x)=1 <---> x=2 or just f(x)=1 <--- x=2?</p>
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<div id="x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>Från:</b> MacOSX-TeX <<a href="mailto:macosx-tex-bounces@email.esm.psu.edu" id="LPlnk556178" class="OWAAutoLink" previewremoved="true">macosx-tex-bounces@email.esm.psu.edu</a>>
för Josep Maria Font <<a href="mailto:jmfont@ub.edu" id="LPlnk835669" class="OWAAutoLink" previewremoved="true">jmfont@ub.edu</a>><br>
<b>Skickat:</b> den 21 augusti 2018 12:15<br>
<b>Till:</b> TeX on Mac OS X Mailing List<br>
<b>Ämne:</b> Re: [OS X TeX] Latex symbol for "define equal"</font>
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<div class="x_PlainText">That's why I prefer to use "when" for definitions: [...this NEW thing happens...] WHEN [...such-and-such known, understandable condition holds...].<br>
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JMaF<br>
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<div>Cheers,</div>
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<div> Ross</div>
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