First, multiple-choice questions (3 points for each small question, 30 points for * * *)
1. The Yangtze River, the longest river in China, is about kilometers long, which is expressed as () by scientific counting method.
A.km.b.km.
Kilometers are kilometers in diameter.
2. The following question is correct ()
A.B.
C.D.
3. The number of negative numbers in is ()
A.B. C. D。
4. The following rights from left to right are ()
A.B.
C.D.
5. A two-digit number, the number on one digit is, the number on the tenth digit is, and the algebraic expression indicates that this two-digit number is ().
A.B. C. D。
The reciprocal of 6 is ()
A.B. C. D。
7. The value of algebraic expression is, then the value of is ().
A.B. C. D。
8. If is, the value of is ()
A.B. C. D。
9. The positions of known numbers,, and on the number axis are shown in the figure, and the result of simplification is ().
A.B. C. D。
10. If,,, then the correct size relationship is ().
A.b； C. D。
Fill in the blanks (3 points for each small question, 30 points for * * *)
1 1. If the water level of the Yellow River is meters higher than the warning water level, it shall be recorded as meters.
So meters means meters above the warning water level.
/kloc-the reciprocal of 0/2. Yes, the countdown is. 13. If, then =
14. Approximate the logarithm by rounding, and keep three significant figures. The result is.
15. and are similar items.
16. Draw a picture with matchsticks as follows. The first picture needs matches.
17. The monomial is a quintic monomial about,,, so n = _ _ _ _ _ _ _ _ _
18. Calculate by calculator: The key sequence is:
, display: _ _ _ _ _ _.
19. If you add a polynomial, then this polynomial is _ _ _ _ _ _ _ _ _ _;
20. Please observe the following formula:
,
,
,
,…
According to the law you found, please write the result of the following formula directly:
___________。
Iii. Answering questions (***60 points)
2 1. Calculation (16 points)
( 1) (2)0
(3) (4)[ ( ) ]÷5
22 (8 points) Simplification and evaluation
(1) Simplify:
(2) simplify first and then evaluate, among which.
23.(8 points) Fill the following figures in the corresponding brackets:
1 1, ,6.5,-8, ,0, 1,- 1,-3. 14
(1) set of positive numbers {…}
(2) Negative Set {…}
(3) Integer set {…}
(4) Positive integer set {…}
(5) Negative integer set {…}
(6) Positive Fraction Set {…}
(7) Negative score set {…}
(8) Rational number set {…}
24.(6 points) Medical research shows that height has certain heritability, so the height of a child can be predicted according to the height of his parents, and the calculation method is as follows:
Son height = (father height+mother height) × 1.08
Daughter height = (father height ×0.923+ mother height)
(1) If the parents are m and n meters tall, please ask others to predict the heights of their sons and daughters when they grow up. (expressed by algebraic expression)
(2) Xiaoming (male) has a father height of1.75m and a mother height of1.62m.. Seek Xiaoming's adult height.
25.(6 points) During the "Eleventh" golden cycle, the number of tourists in Huangshan Scenic Area during the seven-day holiday changes as shown in the following table (a positive number indicates that there are more people than the previous day, and a negative number indicates that there are fewer people than the previous day).
Date 1 2 3 4 5 6 7
Number change (ten thousand people)+1.6+0.8+0.4-0.8+0.2-1.2
(1) Please judge that the day with the largest number of tourists is Japan and the day with the least number is Japan.
They are ten thousand people apart.
(2) If there are at most 30,000 tourists a day, there will be 1 10,000 tourists on September 30th.
26.(8 points) Calculate according to the following procedures and write the answers in the table:
(1) Fill in the form:
Enter n
three
—2
—3
…
Output the answer1111…
(2) Please express the calculation program in the problem by algebra and simplify it.
27.(8 points) Teacher Li gave the students a question: When,
After the topic was finished, Xiao Cong said, "The conditions given by the teacher are redundant." Xiao Ming said: "If you don't give these two conditions, you won't get the result, which is not superfluous." Which do you think is reasonable? Why?
Reference answer:
I. 1。 a2 . D3 . B4 . C5 . D6 . D7 . b8 . B9 . a 10 . c。
Two. 1 1, low. 12、2.5,—0.4。 13、 。 14、5.66× 106。 15、0。 16、2n+ 1 . 17.3;
18.2、0、—、4、×、(—)、5、=,40。 19.；
20. 1000. Prompt: Through observation, it is found that the rule in setting conditions is that the number on the right side of the equation is the complete square of a natural number, which is equal to the square of a natural number on the left, so1+2+3+…+99+100+99+…+3.
Iii. 2 1. ( 1); (2) ; (3) ; (4) .
22.( 1) 。 (2)3.22。
23.( 1) 1 1,6.5, , 1, (2) ,-8,- 1,-3. 14
(3) 1 1,-8,,0, 1,- 1, (4) 1 1, 1.
(5)-8,- 1 (6)6.5,
(7) ,-3. 14 (8) 1 1, ,6.5,-8, ,0, 1,- 1,-3. 14
24.( 1) The height of the son after adulthood: 0.54 (m+n); Adult height of daughter: (0.623 m+ n).
(2) About1.82m. ..
25.( 1)3、7、2.2 , (2) 0.2 .
26. Solution: The algebraic expression is:, and the simplified result is: 1.
27. The original formula is =, and the combined result is 0, which has nothing to do with the values of A and B, so what Xiao Ming said makes sense.