Your Practice Set – Applications and Interpretation for IBDP Mathematics SE Production Limited 82 7 3 0 24 8 29 15 1 12 4 47 21 1 24 8 � � � � � � � � � � � � � � � � � � � � � � B A2 [ 3 ] 1 . Let 6 3 1 1 4 2 1 2 1 � � � � � � � � � � � � � � � A . ( a ) Write down �1 A . [ 2 ] It is given that 1 2 2 0 1 3 2 1 0 3 � � � � � � � � � � � � � � � � AB I , where B and I are 3 3 � matrices . ( b ) Find B . [ 3 ] 2 . Let 3 1 0 2 1 1 1 1 1 � � � � � � � � � � � � � A . ( a ) Write down �1 A . [ 2 ] It is given that 8 5 3 2 6 7 5 5 4 4 � � � � � � � � � � � � � � � AB I , where B and I are 3 3 � matrices . ( b ) Find B . [ 3 ] Exercise 26