计算 (1)9-(+
(2)(
(3)-7×
(4)( -3 )2÷
|
(1)9-(+
)-6+(-8 3
)=9-6-7 3
-8 3
=9-6-5=-2; 7 3
(2)(
-1 3
+3 4
)×(-36)=-(1 6
×36-1 3
×36+3 4
×36)=-(12-27+6)=9;1 6
(3)-7×
+( -5 )×( -5 4
)-5 4
=-2 5
+35 4
-25 4
=-2 5
-5 2
=-2 5
; 29 10
(4)( -3 )2÷
×( -3 4
)-[ 1+( - 2 ) 3 ]=-9×1 2
×4 3
-(1-8)=-6+7=1.1 2