title: CPLEX: Error 5002 Objective is not convex -> Problem can be solved to global optimality with optimality target 3 ->
body: <p>I am receiving this error on CPLEX Optimization studio. The problem is a simple quadratic problem with one equality and two inequality constraints.</p>
  <p>.mod code shown below (no .dat used):</p>
  <pre><code>    /*********************************************
   * OPL 12.10.0.0 Model
   * Author: qdbra
   * Creation Date: Sep 14, 2020 at 9:40:57 PM
   *********************************************/
  
  range R = 1..5;
  range B= 6..10;
  
  dvar float x[R];
  dvar boolean y[B];
  
  minimize
    ( x[1]^2 - 2*x[2]^2 + 3*x[3]^2 + 4*x[4]^2
    - 5*x[5]^2 + 6*y[6]^2 + 7*y[7]^2 - 
    8*y[8]^2 + 9*y[9]^2 + 10*y[10]^2 +
    8*x[1]*x[2] + 17*x[3]*y[8] - 20*y[6]*y[9]
    + 26*y[9]*y[10])/2 ;
    
  subject to {
    ct1: 
    x[1] + x[2] + x[3] + x[5] + y[6] + y[7] == 20;
         
    ct2: 
    x[1] + x[4] + y[8] + y[9] + y[10] &gt;= 1;
         
    ct3: 
    x[2] - x[4] - y[6] + y[7] &gt;= 0;
  }
  </code></pre>