a)
-
(1
-
)
i,
-
-
(1 +
)
i
; b)
-
+ (2 +
)
i,
+ (2
-
)
i
; c) ?; d)
±
(
+
,
±
(
-
; e)
±
(1 +
i
)
,
±
(
+
i
)
.