www . seprodstore . com 325 Answers 24.3 ( a ) ( i ) 10 ( ii ) s 5 � ( b ) 0.15i 0.05i 10 8 z w e e � � � ( c ) ( i ) 10cis0.15 z � ( ii ) 8cis0.05 w � ( d ) ( i ) 2.17 L � ( ii ) 0.523 � � ( e ) 2 2.17cos ( 10 0.523 ) S t � � ( f ) 9.56 24.4 ( a ) ( i ) 7 ( ii ) 1 s ( b ) 0.5i 0.95i 6.3 7 z w e e � � � � � ( c ) ( i ) 6.3cis ( 0.5 ) z � � ( ii ) 7cis ( 0.95 ) w � � ( d ) ( i ) 3.04 L � ( ii ) 1.07 � � ( e ) 2 3.04sin ( 2 1.07 ) V t � � � ( f ) 0.5 0.557 t � � or 1.28 1.5 t � � Chapter 7 25.1 ( a ) 15 ( b ) 3 det 2 4 x x � � B ( c ) 0 x � 25.2 ( a ) 3 ( b ) 2 det 1 x � � B ( c ) 1 x � or 4 x � 25.3 ( a ) 2 det 4 3 x x e e � � A ( b ) 0 x � 25.4 ( a ) 2 det ( ln ) 6 x � � A ( b ) 2 x e � or 3 x e � 26.1 ( a ) 1 1 2 0 3 3 7 11 1 3 3 2 5 7 � � � � � � � � � � � � � � � � � � � � � � � � � � A ( b ) 2 1 7 3 3 3 14 13 40 3 3 3 9 9 24 � � � � � � � � � � � � � � � � � � � � � � � � � B 26.2 ( a ) 1 2 1 1 5 5 5 1 3 3 5 5 5 3 4 1 5 5 5 � � � � � � � � � � � � � � � � � � � � � � � � � A ( b ) 33 13 8 5 5 5 34 14 9 5 5 5 42 7 28 5 5 5 � � � � � � � � � � � � � � � � � � � � � � � B 26.3 ( a ) 1 5 9 1 2 2 1 1 0 2 2 9 15 1 4 4 � � � � � � � � � � � � � � � � � � � � � � � � A ( b ) 1 11 7 4 2 4 113 21 177 4 2 4 15 9 25 4 2 4 � � � � � � � � � � � � � � � � � � � � � � � � C Exercise 25 Exercise 26