Category name
First, fill in the blanks:
1、37 ÷ 34= ; 2、20050= ; 3、〉m = M4；
4. When a, the score is meaningless; When a, the value of the score is 0 (1 minute per space);
5. If 1 nm = 10-9 m, it is expressed by scientific notation120 nm = m;
6. The radius of a bacterium is 1.2 1× 10-5 meters, and the decimal is expressed as meters;
7, known as x=3, the value of the score is zero, then k =；;
8. The simplest common denominator of a score is:
9. If the value of the score is 0, then x =；;
10, if the equation has an increasing root, then a =；;
1 1, it is known that the value of the score is.
12. The bus will travel from place A to place B at the speed of V 1km, and it will take t hours to arrive. If it runs at a speed of V2 kilometers per hour, it can arrive a few hours in advance.
Second, multiple-choice questions (each question has only one correct option)
13, the following:,,, where is the score with () a * *1b, 2 C, 3 D, 4.
14, if the values of x and y are expanded to twice the original values, the values of the following fractions remain unchanged ().
A, B, C, D,
15, the following calculation is correct ()
A, B,
C, D,
16, and the simplified result is ()
A, B, C, D,
17, the correct result of calculation is ()
A, B, C, D,
18. The result of calculation is ()
(A) (B) (C) (D)
19. If > > 0, the value of is ().
(A)0 (B) Positive number (c) Negative number (d) cannot be determined.
20. Zhao Qiang borrowed a 280-page book, which he had to finish within two weeks. When he was in the middle of reading, he found that he had to read 265,438+0 pages every day during the loan period. When he reads the first half, how many pages does he read on average every day? If you read X pages every day on average in the first half of the year, the correct one in the following equation is ().
A, B,
C, D,
Third, answer questions.
2 1, calculation:
22, calculation, and make the result only contains the exponential power of positive integers:
23. Calculation: (1) (2)
(3) ; (4) Calculation:
24.(6 points) Simplify before evaluating: where: x =-2.
Simplify first, then evaluate.
25. Solve the fractional equation: Solve the equation:
26. The typist spends the same time typing 9000 words as typing 7200 words. It is known that two typists A and B type 5400 words per hour. How many words do they type per hour?
27. A classmate planned to walk 30 kilometers to visit the museum, but due to changes in circumstances, he had to ride a bike. The speed of riding a bike was 0.5 times that of 65438+ walking speed, so that he could arrive two hours earlier as required. Ask this classmate the speed of riding a bike.
28. When a shopping mall sells a commodity, it will increase the purchase price of the commodity by 20% in the first month as the sales price, making a profit of 6,000 yuan. In the second month, the mall carried out promotional activities, taking the increase in purchase price of 10% as the sales price. The sales volume in the second month will increase 100 compared with the first month, and the profit of the mall in the second month will be more than that in the first month. How many pieces did the mall sell in the second month?
29. The renovation of the blackboard in the school classroom during the holiday should be completed within the specified date. If it's done by Team A, it will be finished on schedule. If it is done by Engineering Team B, it will be 3 days later than the specified date. As a result, the two teams worked together for two days, and the rest was done by team B alone, just within the stipulated date. What is the appointed date?
answer
1. 1, 27; 2 、 1 ; 3 、 ; 4 、 5 、 ; 6 、 0.00002 1
7、k =-9； 10、a =- 1； 1 1 、 ; 12 、
Second, 13, c; 14、A； 15、D； 16、B； 17、B； 18、D； 19、B； 20、D .
Third, 2 1, 5; 22 、 ; 23 、 ; 24、x； 25 、 ; 26 、 1 ;
27、x+ 1 、- 1； 2 ( x+2)、； 28, x=2 is the root; x =-4；
29. Type A types 3000 words per hour and Type B types 2400 words per hour;
30、7.5; 3 1, 500 yuan, 160; 32 or 6 days.
Fourth, the solution of (1) conjecture is,; Verification: ellipsis
(2) by
∴ , ∴ ,