(1)?3?[?5+(1?2x
)÷(?2)] 2 3
=-3-[-5+(1-
)×(-4 3
)]1 2
=-3-(-5+
)1 6
=
;11 6
(2)?32÷
×(?8 3
)2?(?32×2 3
)×(?1)4 1 2
=-9×
×3 8
-(-9×4 9
)×11 2
=-
+3 2
9 2
=3;
(3)?49
×4823 24
=(-49-
)×4823 24
=-49×48-
×4823 24
=-2398.