Apps. and Interpretation HL Practice Paper Book | Page 27

www . seprodstore . com 15 � Terminologies of matrices : 11 12 1 21 22 2 1 2 n n m m mn a a a a a a a a a � � � � � � � _{� �} � � � � A : A m n � matrix with m rows and n columns ij a : Element on the i th row and the j th column 1 0 0 0 1 0 0 0 1 � � � � � � � _{� �} � � � � I : Identity matrix 0 0 0 0 0 0 0 0 0 � � � � � � � _{� �} � � � � 0 : Zero matrix 11 22 0 0 0 0 0 0 nn a a a � � � � � � � � � � � � : Diagonal matrix � det ( ) A A : Determinant of A A is non-singular if det ( ) 0 � A �1 A : Inverse of A �1 A exists if A is non-singular � For any 2 2 � square matrices a b c d � � � _{� �} � � A : 1 . det ( ) ad bc � � � A A : Determinant of A 2 . 1 1 d b c a ad bc � � � � � � � � � � � A : Inverse of A 16 ^Matrices