Update floating.pro

ElectrostaticsFloating/floating.pro

@@ -144,12 +144,12 @@ FunctionSpace {
      carried by that electrode. Indeed, let us consider the electrostatic weak
      formulation derived in Tutorial 1: find v in Hgrad_v_Ele such that
 
-     (epsilon grad v, grad v')_Vol_Ele + (n . (epsilon grad v), v')_Bnd_Vol_Ele = 0
+     (epsilon grad v, grad v')_Vol_Ele - (n . (epsilon grad v), v')_Bnd_Vol_Ele = 0
 
      holds for all test functions v'. When the test-function v' is BF_electrode,
      the boundary term reduces to
 
-     (n . (epsilon grad v), BF_electrode)_Sur_Electrodes_Ele.
+     -(n . (epsilon grad v), BF_electrode)_Sur_Electrodes_Ele.
 
      Since BF_electrode == 1 on the electrode, the boundary term is actually
      simply equal to the integral of (n . epsilon grad v) on the electrode,