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计算:(1)2×(-5)+22-3÷12 .

(1)2×(-5)+2 3 -3÷12;(2)1 1 2 ×[3× (- 2 3 ) 2 -1]- 1 3

(1)原式=-10+8-4
=-6;

(2)原式=
3
2
×[3×
4
9
-1]-
1
3
×(-8)
=
3
2
×[
4
3
-1]+
8
3

=
3
2
×
1
3
+
8
3

=
1
2
+
8
3

=
19
6


(3)x-
x-1
2
=2-
x+2
3

6x-3(x-1)=12-2(x+2)
6x-3x+3=12-2x-4
6x-3x+2x=12-4-3
5x=5
x=1;

(4)
1
2
[x-
1
3
(x-1)]=
3
4
(2x+1)
x-
1
3
(x-1)=3x+
3
2

6x-2x+2=18x+9
6x-2x-18x=9-2
-14x=7
x=-
1
2

计算(1)2×(-3)+22-3÷12(2)[(-1)2013-(34-16-38)×24]÷|-32+5

(1)2×(-3)+22-3÷

1
2

=-6+4-6
=-8;

(2)[(-1)2013-(
3
4
-
1
6
-
3
8
)×24]÷|-32+5|
=[(-1)-(18-4-9)]÷27
=[(-1)-5]÷27
=-6÷27
=-
2
9

计算:(1)16+(-14)+(-16)-(-4);(2)(512+23?34)×(?12);(3)2×(?5)+22?3÷12;(4)?22+60

(1)原式=16-14-16+4
=16-16-14+4
=-10;

(2)原式=

5
12
×(-12)+
2
3
×(-12)-
3
4
×(-12)
=-5-8+9
=-13+9
=-4;

(3)原式=-10+4-3×2
=-10+4-6
=-12;

(4)原式=-4+10×(-
1
6

=-4-
5
3

=-
17
3


(5)原式=0.25×(-8)-[4×
9
4
+1]
=-2-[9+1]
=-2-10
=-12.

计算:(1)(-2)2×5-(-2)3÷4(2)-12-(3-5)+32×(1-3

(1)原式=4×5-(-8)÷4=20+2=22;
(2)原式=-1-(-2)+9×(-2)
=-1+2-18
=-19+2
=-17.

计算:(1)23×5-(-113)×5+(-1)×5;(2)-22-32×2+(-2)3÷(-12)

(1)原式=(

2
3
+1
1
3
-1)×5
=1×5
=5;

(2)原式=-4-3+(-8)×(-2)
=-4-3+16
=9.

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