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Wiki/Math/Matricies/Determinant of a Matrix.md

@@ -0,0 +1,10 @@
+For a 2 x 2 matrix:
+$$ \det\begin{pmatrix}
+a&b\\c&d
+\end{pmatrix} = \begin{vmatrix} a&b\\c&d\end{vmatrix} = ad-bc$$
+For a 3 x 3 matrix:
+$$\begin{vmatrix} a&b&c\\d&e&f\\g&h&i\end{vmatrix} = a\begin{vmatrix} e&f\\h&i\end{vmatrix} - b\begin{vmatrix} d&f\\g&i\end{vmatrix} + c\begin{vmatrix} d&e\\g&h\end{vmatrix} = a(ei-hf)-b(di-gf)+c(dh-ge)$$
+### Properties
+$$\begin{matrix}
+a&b\\a&b
+\end{matrix}$$

Wiki/Math/Vector Basics.md

@@ -22,6 +22,8 @@ Used to find the vector of magnitude 1 in the same direction as $u$
 $$a \times b = \begin{vmatrix} i&j&k\\a_1&a_2&a_3\\b_1&b_2&b_3\end{vmatrix}= i(a_2b_3-a_3b_2)-j(a_1b_3-a_3b_1)+k(a_1b_2-a_2b_1)$$
 Used to create a vector that is orthogonal to both $a$ and $b$. To find what direction it will point in use the right-hand rule (thumb, pointer and middle finger).
 
+The cross product is calculated by finding the [[Determinant of a Matrix|determinant]] of the matrix formed in the equation above with the unit vectors in the top row.
+
 Properties:
 - Not commutative $$u\times v \ne v \times u$$
 - Anti-commutative $$ u \times v = -(v \times u) $$