Update 5_atoms_and_lcao_solutions.md

src/5_atoms_and_lcao_solutions.md

@@ -39,10 +39,10 @@ $$
 
 2. $$
     H = -\frac{mV_0^2}{ħ^2}\begin{pmatrix}
-        1/2+\exp(-\frac{2mV_0}{ħ^2}(x_2-x_1)) &
-        \exp(-\frac{mV_0}{ħ^2}(x_2-x_1))\\
-        \exp(-\frac{mV_0}{ħ^2}(x_2-x_1)) &
-        1/2+\exp(-\frac{2mV_0}{ħ^2}(x_2-x_1))
+        1/2+\exp(-\frac{2mV_0}{ħ^2}|x_2-x_1|) &
+        \exp(-\frac{mV_0}{ħ^2}|x_2-x_1|)\\
+        \exp(-\frac{mV_0}{ħ^2}|x_2-x_1|) &
+        1/2+\exp(-\frac{2mV_0}{ħ^2}|x_2-x_1|)
     \end{pmatrix}
   $$