<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=utf-8"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style><!--
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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black'>Dear all,<br><br>I have a quadratic model with continuous variables in the form of:<br><br> Maximize Z = sum(i, ai * Xi) - sum(i, sum(j, bij * Xi * Xj))<br> Subject to: 0 <= Xi <=1<br><br>which ai and bij are non-negative coefficient.<br>I want to know, is the ipopt could solve this model <b>optimally </b>or not?<br>Note: It has been proved that the solution of the above continuous model is integer.<br>Please help me, about this question.<br><br>Thanks.<br>M. Reisi</span><span style='font-family:"Tahoma","sans-serif";color:black'><o:p></o:p></span></p></div></body></html>