Update src/1_complex_numbers.md

src/1_complex_numbers.md

@@ -287,13 +287,12 @@ function help in re-deriving trigonometric identities.
 
 ## 1.6. Problems
 
-1.  [:grinning:]  Given $a=1+2\rm i$ and $b=-3+4\rm i$, calculate and draw in the
-    complex plane the numbers:
-        1.  $a+b$, 
-        2.  $ab$,
-        3.  $b/a$.
+1.  [:grinning:]  Given $a=1+2\rm i$ and $b=-3+4\rm i$, calculate and draw in the complex plane the numbers:
+    1.  $a+b$,
+    2.  $ab$, 
+    3.  $b/a$.
 
-2.  [:grinning:] Evaluate 
+2.  [:grinning:] Evaluate  
         (a) $\rm i^{1/4}$, 
         (b) $\left(1+\rm i \sqrt{3}\right)^{1/2}$,
         (c) $\exp(2\rm i^3)$.