fix typos

src/10_xray_solutions.md

@@ -54,7 +54,7 @@ Brillouin zone is most easily given by the Wigner Seitz unit cell (see notes) by
 
 ??? hint "First small hint"
 
-    The $(hkl)$ plane intersects lattice at position vectors of \frac{\mathbf{a_1}}{h}, \frac{\mathbf{a_2}}{k}, \frac{\mathbf{a_1}}{l}. Can you define a general vector inside the $(hkl)$ plane? 
+    The $(hkl)$ plane intersects lattice at position vectors of $\frac{\mathbf{a_1}}{h}, \frac{\mathbf{a_2}}{k}, \frac{\mathbf{a_1}}{l}$. Can you define a general vector inside the $(hkl)$ plane? 
     
 ??? hint "Second small hint"
 
@@ -114,6 +114,7 @@ plt.annotate('$\mathbf{k}$',(-8,18),fontsize=14, ha='center',color='b')
 # k' vector
 plt.arrow(-6,37.4,6+13.4*2,-37.4+18.4,color='k',zorder=11,head_width=2,length_includes_head=True)
 plt.annotate('$\mathbf{k\'}$',(15,30),fontsize=14, ha='center',color='k')
+plt.show()
 ```
 ## Exercise 4: Structure factors