Update HOME_EXAM.md

HOME_EXAM.md

@@ -339,7 +339,7 @@ A mutable reference to some expression
 ```
 
 ```math
-\frac{<e,σ> → \text{ ref mut } v}{<*e,σ> → mv}
+\frac{<e,σ> → \text{ ref } mv}{<*e,σ> → mv}
 ```
 Dereference of a referenced expression
 ``` rust
@@ -348,7 +348,7 @@ Dereference of a referenced expression
 
 ### Function call expression
 ```math
-\frac{<e_1, σ> → <n_1, σ^1> ... <e_n, σ^(n-1)> → <n_n, σ^n>}{<f(e_1, ..., e_n), σ> → <n, σ'>}
+\frac{<e_1, σ> → <n_1, σ^1> ... <e_n, σ^n^-^1> → <n_n, σ^n>}{<f(e_1, ..., e_n), σ> → <n, σ'>}
 ```