( 1)3.28-4.76+ 1 - ;
(2)2.75-2 -3 + 1 ;
(3)42÷(- 1 )- 1 ÷(-0. 125);
(4)(-48) ÷82-(-25) ÷(-6)2;
(5)- +( )×(-2.4).
2. Calculation problem: (10 ′× 5 = 50 ′)
( 1)-23÷ 1 ×(- 1 )2÷( 1 )2;
(2)- 14-(2-0.5)× ×[( )2-( )3];
(3)- 1 ×[ 1-3×(- )2]-( )2×(-2)3÷(- )3
(4)(0. 12+0.32) ÷ [-22+(-3)2-3 × ];
(5)-6.24×32+3 1.2×(-2)3+(-0.5 1) ×624.
[-|98|+76+(-87)]*23[56+(-75)-(7)]-(8+4+3)
5+2 1*8/2-6-59
68/2 1-8- 1 1*8+6 1
-2/9-7/9-56
4.6-(-3/4+ 1.6-4-3/4)
1/2+3+5/6-7/ 12
[2/3-4- 1/4*(-0.4)]/ 1/3+2
22+(-4)+(-2)+4*3
-2*8-8* 1/2+8/ 1/8
(2/3+ 1/2)/(- 1/ 12)*(- 12)
(-28)/(-6+4)+(- 1)
2/(-2)+0/7-(-8)*(-2)
( 1/4-5/6+ 1/3+2/3)/ 1/2
18-6/(-3)*(-2)
(5+3/8*8/30/(-2)-3
(-84)/2*(-3)/(-6)
1/2*(-4/ 15)/2/3
-3x+2y-5x-7y
75÷〔 138÷( 100-54)〕 85×(95- 1440÷24)
80400-(4300+870÷ 15) 240×78÷( 154- 1 15)
1437×27+27×563 〔75-( 12+ 18)〕÷ 15
2 160÷〔(83-79)× 18〕 280+840÷24×5
325÷ 13×(266-250) 85×(95- 1440÷24)
58870÷( 105+20×2) 1437×27+27×563
8 1432÷( 13×52+78) [37.85-(7.85+6.4)] ×30
156×[( 17.7-7.2)÷3] (947-599)+76×64
36×(9 13-276÷23) [ 192-(54+38)]×67
[(7. 1-5.6)×0.9- 1. 15]÷2.5 8 1432÷( 13×52+78)
5.4÷[2.6×(3.7-2.9)+0.62] (947-599)+76×64 60-(9.5+28.9)]÷0. 18 2.88 1÷0.43-0.24×3.5 20×[(2.44- 1.8)÷0.4+0. 15] 28-(3.4 / kloc-0/.25×2.4) 0.8×〔 15.5-(3.2 1 5.79)〕 (3 1.8 3.2×4)÷5 194-64.8÷ 1.8×0.9 36.72÷4.25×9.9 3.4 16÷(0.0 16×35) 0.8×[( 10-6.76)÷ 1.2]
( 136+64)×(65-345÷23) (6.8-6.8×0.55)÷8.5
0. 12× 4.8÷0. 12×4.8 (58+37)÷(64-9×5)
8 12-700÷(9+3 1× 1 1) (3.2× 1.5+2.5)÷ 1.6
85+ 14×( 14+208÷26) 120-36×4÷ 18+35
(284+ 16)×(5 12-8208÷ 18) 9.72× 1.6- 18.305÷7
4/7÷[ 1/3×(3/5-3/ 10)] (4/5+ 1/4)÷7/3+7/ 10
12.78-0÷( 13.4+ 156.6 ) 37.8 12-700÷(9+3 1× 1 1) ( 136+64)×(65-345÷23) 3.2×( 1.5+2.5)÷ 1.6
85+ 14×( 14+208÷26) (58+37)÷(64-9×5)
(6.8-6.8×0.55)÷8.5 (284+ 16)×(5 12-8208÷ 18)
0. 12× 4.8÷0. 12×4.8 (3.2× 1.5+2.5)÷ 1.6
120-36×4÷ 18+35 10. 15- 10.75×0.4-5.7
5.8×(3.87-0. 13)+4.2×3.74 347+45×2-4 160÷52
32.52-(6+9.728÷3.2)×2.5 87(58+37)÷(64-9×5)
[(7. 1-5.6)×0.9- 1. 15] ÷2.5 (3.2× 1.5+2.5)÷ 1.6
5.4÷[2.6×(3.7-2.9)+0.62] 12×6÷( 12-7.2)-6
3.2×6+( 1.5+2.5)÷ 1.6 (3.2× 1.5+2.5)÷ 1.6
5.8×(3.87-0. 13)+4.2×3.74
33.02-( 148.4-90.85)÷2.5
(1) Calculation problem:
( 1)23+(-73)
(2)(-84)+(-49)
(3)7+(-2.04)
(4)4.23+(-7.57)
(5)(-7/3)+(-7/6)
(6)9/4+(-3/2)
(7)3.75+(2.25)+5/4
(8)-3.75+(+5/4)+(- 1.5)
(9)(- 17/4)+(- 10/3)+(+ 13/3)+( 1 1/3)
( 10)(- 1.8)+(+0.2)+(- 1.7)+(0. 1)+(+ 1.8)+(+ 1.4)
( 1 1)(+ 1.3)-(+ 17/7)
( 12)(-2)-(+2/3)
( 13)|(-7.2)-(-6.3)+( 1. 1)|
( 14)|(-5/4)-(-3/4)|-| 1-5/4-|-3/4|)
( 15)(-2/ 199)*(-7/6-3/2+8/3)
( 16)4a)*(-3b)*(5c)* 1/6
1.3/7 × 49/9 - 4/3
2.8/9 × 15/36 + 1/27
3. 12× 5/6 – 2/9 ×3
4.8× 5/4 + 1/4
5.6÷ 3/8 – 3/8 ÷6
6.4/7 × 5/9 + 3/7 × 5/9
7.5/2 -( 3/2 + 4/5 )
8.7/8 + ( 1/8 + 1/9 )
9.9 × 5/6 + 5/6
10.3/4 × 8/9 - 1/3
0. 12χ+ 1.8×0.9=7.2 (9-5χ)×0.3= 1.02 6.4χ-χ=28+4.4
1 1.7 × 5/49 + 3/ 14
12.6 ×( 1/2 + 2/3 )
13.8 × 4/5 + 8 × 1 1/5
14.3 1 × 5/6 – 5/6
15.9/7 - ( 2/7 – 10/2 1 )
16.5/9 × 18 – 14 × 2/7
17.4/5 × 25/ 16 + 2/3 × 3/4
18. 14 × 8/7 – 5/6 × 12/ 15
19. 17/32 – 3/4 × 9/24
20.3 × 2/9 + 1/3
2 1.5/7 × 3/25 + 3/7
22.3/ 14 ×× 2/3 + 1/6
23. 1/5 × 2/3 + 5/6
24.9/22 + 1/ 1 1 ÷ 1/2
25.5/3 × 1 1/5 + 4/3
26.45 × 2/3 + 1/3 × 15
27.7/ 19 + 12/ 19 × 5/6
28. 1/4 + 3/4 ÷ 2/3
29.8/7 × 2 1/ 16 + 1/2
30. 10 1 × 1/5 – 1/5 × 2 1
3 1.50+ 160÷40 (58+370)÷(64-45)
32. 120- 144÷ 18+35
33.347+45×2-4 160÷52
34(58+37)÷(64-9×5)
35.95÷(64-45)
36. 178- 145÷5×6+42 420+580-64×2 1÷28
37.8 12-700÷(9+3 1× 1 1) ( 136+64)×(65-345÷23)
38.85+ 14×( 14+208÷26)
39.(284+ 16)×(5 12-8208÷ 18)
40. 120-36×4÷ 18+35
4 1.(58+37)÷(64-9×5)
42.(6.8-6.8×0.55)÷8.5
43.0. 12× 4.8÷0. 12×4.8
44.(3.2× 1.5+2.5)÷ 1.6 (2)3.2×( 1.5+2.5)÷ 1.6
45.6- 1.6÷4= 5.38+7.85-5.37=
46.7.2÷0.8- 1.2×5= 6- 1. 19×3-0.43=
47.6.5×(4.8- 1.2×4)= 0.68× 1.9+0.32× 1.9
48. 10. 15- 10.75×0.4-5.7
49.5.8×(3.87-0. 13)+4.2×3.74
50.32.52-(6+9.728÷3.2)×2.5
5 1.-5+58+ 13+90+78-(-56)+50
52.-7*2-57/(3
53.(-7)*2/( 1/3)+79/(3+6/4)
54. 123+456+789+98/(-4)
55.369/33-(-54-3 1/ 15.5)
56.39+{3x[42/2x(3x8)]}
57.9x8x7/5x(4+6)
58. 1 1x 22/(4+ 12/2)
59.94+(-60)/ 10
1.
a^3-2b^3+ab(2a-b)
=a^3+2a^2b-2b^3-ab^2
=a^2(a+2b)-b^2(2b+a)
=(a+2b)(a^2-b^2)
=(a+2b)(a+b)(a-b)
2.
(x^2+y^2)^2-4y(x^2+y^2)+4y^2
=(x^2+y^2-2y)^2
3.
(x^2+2x)^2+3(x^2+2x)+x^2+2x+3
=(x^2+2x)^2+4(x^2+2x)+3
=(x^2+2x+3)(x^2+2x+ 1)
=(x^2+2x+3)(x+ 1)^2
4.
(a+ 1)(a+2)+(2a+ 1)(a-2)- 12
=a^2+3a+2+2a^2-3a-2- 12
=3a^2- 12
=3(a+2)(a-2)
5.
x^2(y+z)^2-2xy(x-z)(y+z)+y^2(x-z)^2
=[x(y+z)-y(x-z)]^2
=(xz+yz)^2
=z^2(x+y)^2
6.
3(a+2)^2+28(a+2)-20
=[3(a+2)-2][(a+2)+ 10]
=(3a+4)(a+ 12)
7.
(a+b)^2-(b-c)^2+a^2-c^2
=(a+b)^2-c^2+a^2-(b-c)^2
=(a+b+c)(a+b-c)+(a+b-c)(a-b+c)
=(a+b-c)(a+b+c+a-b+c)
=2(a+b-c)(a+c)
8.
x(x+ 1)(x^2+x- 1)-2
=(x^2+x)(x^2+x- 1)-2
=(x^2+x)^2-(x^2+x)-2
=(x^2+x-2)(x^2+x+ 1)
=(x+2)(x- 1)(x^2+x+ 1)