[-3]+[-2]+[- 1]+0+ 1+2= -3
[-30 1]+ 125+30 1+[-75]= 50
[- 1]+[- 1/2]+3/4+[- 1/4]= - 1
[-7/2]+5/6+[-0.5]+4/5+ 19/6= 1.25
[-26.54]+[-6. 14]+ 18.54+6. 14= -8
1. 125+[- 17/5]+[- 1/8]+[-0.6]= -3
[-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 1, the "Dawning 3000 Super Server" developed in China, its peak operation speed reaches 403,200,000,000 times per second, which can be expressed as () by scientific counting method.
A.4032× 108 b . 403.2× 109 c . 4.032× 10 1 1d . 0.4032× 10 12
2. The following four figures are each composed of six identical small squares, and the one that can be folded into a cube is ().
3. In the following groups, the equal group is ()
A.- 1 and -4+(-3) B. |-3| and -(-3) c.3x2-2x = x d.2x+3x = 5x2.
4. The time difference between Paris and Beijing is -7 (a positive number means that the same moment is several hours earlier than Beijing), if Beijing time is July 2 14: 00.
When the whole, then Paris time is ()
A. July 2nd 2 1 point B. July 2nd 7 o'clock C. July 1 point 7 o'clock D. July 2nd 5 o'clock.
5. The tax payment method of deposit interest stipulated by the state is: interest tax = interest ×20%, and the bank's one-year fixed interest rate is 2.25%, which is less now.
When Lei takes out the principal and interest due in one year, he pays interest tax in 4.5 yuan, so the money deposited in the bank a year ago is A. 1000 yuan B. 900 yuan C. 800 yuan D. 700 yuan ().
6, a brand of color TV after 30% price reduction, each price is one yuan, then the brand of color TV each price is ().
A.0.7a yuan B. 0.3a yuan C.D.
7, in the angle formed by two intersecting straight lines ()
A. there must be an obtuse angle B. there must be an acute angle C. there must be a non-obtuse angle D. there must be two acute angles.
8. In order to make people feel the impact of discarded plastic bags on the environment, six students from an environmental protection group recorded the number of discarded plastic bags in their homes in one class. The results are as follows: 33 25 28 26 25 3 1. If there are 45 students in this class, according to the data provided, it is estimated that the total number of discarded plastic bags in all classes this week is about ().
a . 900 b . 1080 c . 1260d . 1800。
9. If the equations about x 3x+5 = m and x-2m = 5 have the same solution, then the value of x is ().
A.3b–3c–4d
10, known as │m+3│+3(n-2)2=0, then the value of m n is ().
A. 6th century BC to 9th century BC
1 1. The following statement is true ()
A through a point outside a straight line, countless straight lines can be made parallel to known straight lines. B. Passing a point can make countless straight lines perpendicular to known straight lines.
C. only two straight lines pass through two points. D. between two points, the line segment is the shortest.
12, in the cross section of the cube, the polygon with the largest number of sides is ().
A. quadrilateral pentagon hexagon heptagon
Second, fill in the blanks
13. When calculating 4× (0.2-3)+(-2) 4 with a calculator, the order of keys is
14, calculate 5136 ˊ = _ _ _ _ _
15, Zhang bought a newspaper from the newspaper at the price of 0.4 yuan, sold B newspapers at the price of 0.5 yuan, and returned the rest to the newspaper at the price of 0.2 yuan, so Zhang's newspaper sales revenue was _ _ _ _ _ _ _ _.
16, it is known that, as shown in the figure, the line segment AB=3.8㎝, AC= 1.4㎝, and d is the midpoint of CB.
A C D B is DB =?
17, let the number of faces of a cuboid be f, the number of sides be v and the number of vertices be e, then f+v f+v+e = _ _ _ _ _ _ _ _
18. Use black and white hexagonal floor tiles to make several patterns according to the following rules:
Then there are _ _ _ _ _ white floor tiles with (No.4) pattern; No, no.
(1) (2) (3) There are _ _ _ _ _ _ _ blocks of white floor tiles.
19. There are five white balls, four yellow balls and 1 red ball in a bag (each ball is the same except the color), so the chances of touching _ _ _ _ _ _ _ balls are the least.
20. It costs less money in 2 yuan to buy 10 kg eggs at a time at a 20% discount than at a 10% discount, so the original price of 10 kg eggs is _ _ _ _ _ _ _.
2 1. Do you like Lamian Noodles? The master of the ramen noodle restaurant, holding a piece of coarse noodles, squeezed the two ends together and stretched them, then squeezed them, stretched them again and again for several times, and then pulled the coarse noodles into many fine noodles, as shown in the sketch below:
……
After the first kneading, after the second kneading and after the third kneading.
After the first kneading, 128 fine noodles can be pulled out.
22. If x= 1, the value of algebraic expression AX3+BX+ 1 is 5; if x=- 1, the value of algebraic expression AX3+BX+ 1 is equal to.
Third, answer questions.
23. Calculate 136× (-) 2② ∣ (-2) 3x0.5 ∣-1.6) 2÷ (-2) 2.
③14 (ABC-2a)+3 (6a-2abc) 49x+6x =-2-3 (x-x2), where x =-2.
24. Solve equation ①-=1② (x+1) = 2-(x+2).
③ { [ ( x+5)-4]+3}=2 ④ - =- 1.6
25. Fill in -6, -5, -4,-1, 0, 1, 4, 5, 6 in the nine squares in the figure below, so that the sum of the three numbers in each row, column and diagonal is equal.
26. There are three points on a straight line, A, B and C, AB=4cm, BC=0.5AB, and point O is the midpoint of line segment AC. Find the length of line segment OB.
Students in a school marched at a speed of 8 km/h. At the end of the line, the headmaster asked a student to run to the front of the line and ask the leader to convey an instruction, and then immediately returned to the end of the line. The student's speed is 12km/h, and it takes 3.6 minutes to go from the end of the line to the end of the line and back again.
In the "Giving Love" activity, all the students in a class donated books. Donations are as follows:
The number of books donated by each person is 5 10 15 20.
The corresponding number of books donated is 17 22 4 2.
Answer the following questions according to the conditions given in the title:
(1) How many students are there in this class? (2) the whole class donated a book;
(3) Make the above data into an appropriate statistical chart.
29. Star Juice Shop Class A juice is more expensive than Class B juice 1 yuan. Xiao Bin and his classmates asked for 3 cups of B-type juice and 2 cups of A-type juice, which cost 16 yuan. What is the unit price of juice A and juice B respectively?
30. Recently, "Shanghai Middle School" launched the "Buy 200 yuan and Send 80 yuan" reward activity. At present, a customer bought a dress made in 200 yuan and got a shopping voucher made in 80 yuan (you can use it in the shopping mall, but you can't exchange money). When the customer bought this dress, a salesman said to the customer, "It is cheaper to buy goods in the reward activity, which is equivalent to a 60% discount, that is, 100% = 60.
3 1. A material supplier implements the following preferential measures for customers: no preferential treatment will be given to those whose one-time purchase amount does not exceed 1 10,000 yuan; One-time purchase of super
If it exceeds 10000 yuan, but does not exceed 30000 yuan, a discount of 10% will be given; A purchase of more than 30 thousand yuan, of which 30 thousand yuan discount 10%, super
There is a 20% discount for those over 30 thousand. Due to the storage capacity problem, a factory paid 7800 yuan for the first time to buy materials from the supplier, and the second time.
The purchase price is 26 100 yuan. If he buys the same amount of materials at one time, how much can he pay less?
I. Fill in the blanks (3 points for each small question, 24 points for * * *)
1.(- 1)2002-(- 1)2003=_________________.
Answer: 2
2. It is known that a certain number is larger than it. If a number is x, the equation _ _ _ _ _ _ _ _ _ _ _.
Answer: x=x+
3. As shown in figure 1, points A, B, C and D are on the straight line L, then BC = _ _ _ _ _ _ _-CD, AB+_ _ _ _ _+CD = AD; If AB=BC=CD, AB = _ _ _ _ _ _ BD.
Figure 1
Answer: BD, BC,
4. If ∠ α = 4132', its complementary angle is _ _ _ _ _ _ _ _, and its complementary angle is _ _ _ _ _ _.
Answer: 48 28', 138 28'
5. As shown in Figure 2, find the following angles: ≈1= _ _ _ _ _ _ _ _ _ _, ≈ 2 = _ _ _ _ _ _ _ _ _, ≈3 = _ _ _ _ _ _ _ _.
Figure 2
Answer: 62.5,25 130.
6. Two straight lines intersect, and there are _ _ _ _ _ _ _ _ intersections; Every two of the three straight lines intersect the largest _ _ _ _ _ _ _ _ and the smallest _ _ _ _ _ _.
Answer: and only one, three, one.
7.38 12′=_____________ ,67.5 =__________ ___________′.
Answer: 38.2, 67, 30
8. If x2-3x = 1 is a linear equation about x, then a = _ _ _ _ _ _ _ _ _ _ _ _
Answer:
Second, multiple-choice questions: (3 points for each small question, ***24 points)
9. Of the following statements, the correct one is
A.| A | is not a negative number B.-A is a negative number.
C.-(-a) must be positive. D. is not an integer.
Answer: a.
10. There are any three points on the plane. Draw a straight line through two of them, and you can draw * * *.
A. One straight line B. Two straight lines C. Three straight lines D. One or three straight lines
Answer: D.
1 1. Of the following drawing statements, the correct one is
A. draw a ray op = 3 cm B. connect point a and point B.
C. draw the midpoint between a and B. Draw the distance between a and b.
Answer: B.
12. The following figures can be folded into cubes.
Figure 3
1。
Answer: D.
13. The following figure is obtained by rotating the left figure around the straight line L.
Figure 4
Answer: D.
14. Figure 5 is a statistical map of crops in a village, in which the proportion of rice is
Figure 5
A.40% B.72% C.48% D.52%
Answer: C.
15. The following statement is correct.
① All right angles are equal; ② All complementary angles are equal; ③ The complementary angles of equal angles are equal; ④ Equal angles are right angles. Among them, the correct one is that
A.①② B.①③ C.②③ D.③④
Answer: B.
16. If | x-|+(2y+ 1) 2 = 0, the value of x2+ y2 is
A.B.
C.- D ...
Answer: B.
Third, answer the following questions
17. Calculation problem (3 points for each small question, *** 12 points)
( 1)(- )×(- 1 )÷(- 1 ) (2)32÷(-2)3+(-2)3×(- )-22
(3)( - )÷( - )2÷(-6)2-(- )2
(4) 1 ×〔3×(- )2- 1〕- 〔(-2)2-(4.5)÷3〕
Answer: (1)-1(2)-2 (3)-(4)-
18. Solve the equation: (5 points for each small question, *** 10)
( 1)〔x-)-8〕x+ 1
(2) - - =0
Answer: (1) x =-(2) x =-
19.(6 points) As shown in Figure 6, it is known that AOB is a straight line, OC bisects ∠AOD, ∠ BOD = 50, and the degree of ∠AOC is found.
Figure 6
Answer: 65
20.(6 points) The complementary angle of an angle is 3 times larger than that of this angle 18. Find the degree of this angle.
Answer: 36
2 1.(6 points) Make an appropriate statistical chart to represent the data in the following table:
After the previous population censuses in China 1949
Year1953196419821990 2000.
Population (billion) 5.946.9510.081.3412.95.
Answer: You can make a bar chart (abbreviated).
22.( 12 minutes) The bus is 200 meters long and the truck is 280 meters long. They travel in opposite directions on parallel tracks. It takes 18 s from two cars meeting to two cars leaving each other. As we all know, the speed ratio of passenger cars to trucks is 5: 3. How many meters do two cars travel per second?
Solution: If the speed of bus is 5x, the speed of truck is 3x.
18(5x+3x)=200+280。
X=, that is, the bus speed is m/s and the truck speed is10m/s75 ÷ [138 ÷ (100-54)] 85× (95-1440 ÷).
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)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)
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)1,No.2 in row 5 of the Olympic Stadium can be represented by (5,2), then (7,4). Fine soft hair or feathers.
The arithmetic square root of 2.8 1 is _ _ _ _, = _ _ _ _ _.
3. The positive integer solution of inequality -4x ≥- 12 is.
4. In order to make it meaningful, the value range of X is _ _ _ _ _ _ _ _.
5. In △ABC, it is known that both sides A = 3 and B = 4, so the value range of the third side C is _ _ _ _ _ _ _ _.
6. If one side of an isosceles triangle is equal to 5 and the other side is equal to 8, then the circumference is _ _ _ _ _ _ _.
7. As shown in the figure, please add a condition to make AD‖BC.
8. If the cube root of a number is itself, then the number is.
9. The coordinates of the point P (-2, 1) moving up by 2 units are.
10. Observe the following equation, =2, =3, =4. Please write a list containing n (n >); The equation of 2) represents the general formula of the above laws:.
Students, I am Fuwa Jingjing. What's the answer to Huanhuan's question? I'm in trouble. The teacher gave me some multiple-choice questions. I didn't meet the teacher's requirements, and I couldn't get the logo. It's all up to you (***20 yuan, two yuan for each question).
1 1. The Olympic Games need a polygonal tile to lay a seamless floor. The purchased tile shape cannot be ().
A, equilateral triangle; B, square; C, regular octagon; Regular hexagon
12, with the following statement:
(1) irrational number is an inexhaustible number; (2) Irrational numbers are infinitely cyclic decimals;
(3) Irrational numbers include positive irrational numbers, zero irrational numbers and negative irrational numbers; (4) Irrational numbers can be represented by points on the number axis. The correct statement is ()
A. 1
13, in,, 3. 14, 2+,-,0, 1.22666 …, the number of irrational numbers is ().
A.3 B. 4 C. 5 D.6
14. Known
a . a+5 & gt； b+5？ B.3a>。 3b； C.-5a >-5b？ d . >；
15. Let "●", ▲ "and ■" represent three different objects and weigh them twice with a balance, as shown in Figure 2. Then, these three objects are arranged as () in descending order of mass.
A.■●▲ B. ■▲● C. ▲●■ D. ▲■●
16, if the solution set of the inequality group is-1≤x≤3, the correct representation in the figure is ().
17, given that point M(3a-9, 1-a) is in the third quadrant, and its coordinates are integers, then a= ().
A. 1
18, Beijing will hold an Olympic commemorative stamp exhibition. If each person has three stamps, there will be 24 more. If there are four stamps per person, there will be 26 less stamps. The number of stamps on display is: ()
a、 174 B、 178 C、 168 D、 164
19. In order to welcome the Olympic Games and protect the ecological environment, a county in our province responded to the national call of "returning farmland to forests" and changed part of cultivated land into forest land. After the change, the forestland area and cultivated land area * * * are 180 square kilometers, and the cultivated land area is 25% of the forestland area. In order to find out how many square kilometers the forestland area and cultivated land area are after the change. Let the changed cultivated land area be x square kilometers and the forestland area be y square kilometers. According to the meaning of the question, list the following four equations, of which the correct one is ().
A B C D
20. In an Olympic knowledge contest, there are 20 multiple-choice questions. The grading standard is: 1 5 points for the question, 2 points for the wrong 1 question, no points or points for not answering the question. Fuwa Jingjing has two unresolved issues. Answer at least a few questions correctly, and the total score will not be less than 60 points. Then Jingjing's at least correct number of questions is ().
A.7 Questions B.8, C.9 and D. 10
Third, Fuwa Beibei ran over and said to everyone, "Hurry up, the Olympic Committee is recruiting scorekeepers, scorekeepers. Let's go and have a look. " When they got there, it turned out that they were qualified. You must answer the following questions correctly. Can you do it? (**20 sheets, 5 sheets for each question)
(2 1)
(22) Solving inequality 2x- 1
(23)
(24).
Yingying brought a drawing of the Olympic venues. It is known that in △ABC, AD and AE are bisectors of the height and angle of △ABC respectively. If ∠ B = 30 and ∠ C = 50, can you help the master worker solve the following problems?
(1) Find the degree of ∠DAE. (5 pieces)
(2) What is the relationship between ∠ DAE and ∠C-∠B? (No proof required) (3 pieces)
26. Fuwa Yingying is going to buy a kitten and a puppy toy. Instead of telling Yingying the price of toys, the store gave her the following information to calculate the price of each kitten and puppy together with Yingying! (8 pieces)
A * * * to 70 yuan;
A * * * wants 50 yuan.
27.BOCOG will choose a company from A and B to print some Olympic commemorative books. A company puts forward that the design fee and processing fee are * * 1500 yuan, and each book is charged with material fee. 5 yuan: Company B proposed that each book should be charged with material fees and processing fees ***8 yuan, but not design fees. The number of albums to be produced is X, which is charged by Company A..
(1) Please write down the relationship between the album number X for making the commemorative album and the charge (RMB) of Company A; (3 pieces)
(2) Please write down the relationship between the album number X for making the commemorative album and the expenses (yuan) of Company B; (3 pieces)
(3) If you go to Company A and Company B to order commemorative books, which company do you think has the best price? Please write down the analysis reasons. (6 pieces)
Finally, five Fuwa took us to visit the "Bird's Nest" of the National Stadium. VIP tickets are 20% off for group tickets with more than 20 people (including 20 people) in 30 yuan. Our party has 18 people (including Fuwa). When the captain Huanhuan prepared change at the ticket office to buy 18 tickets, Jingjing, who loves thinking, stopped Huanhuan.
(1) Please calculate, is Jingjing's proposal correct? Is it really "wasteful"? (4 pieces)
(2) When the number of people is less than 20, how many people should go to the "Bird's Nest"? Is it more economical to buy 20 tickets? (8 pieces)