2. At 8: 40 on May 23rd, a special train loaded with 2,400 tons of "Love" rice was sent to Sichuan disaster area by Harbin Railway Bureau. On the way, I had to stop three times because I had to change cars. I drove all the way quickly and arrived in Chengdu 80 hours later. The general picture describing the above process is ().
3 Fold the edge as shown in the figure, so that the point coincides with the midpoint of the edge. In the following conclusions: ① sum; ② ;
③ ;
(4) the correct number is ()
a . 1b . 2c . 3d . 4
As shown in the figure, in the quadrilateral ABCD, the moving point P starts from point A and follows ABC D.
The path advances at a constant speed until d, during which the area s of △APD changes with time t.
The correct expression of the relationship with the image is ()
As shown in the figure, in the square paper ABCD, diagonal AC and BD intersect at point O. Fold the square paper ABCD so that AD falls on BD, and point A coincides with point F on BD. After unfolding, the crease DE intersects AB and AC at points E and G, respectively, and connects GF. The following conclusions are drawn: ① AGD = 1 12.5. ②tan∠AED = 2； ③S△AGD = S△OGD； ④ The quadrilateral AEFG is rhombic; ⑤BE = 20g。 The serial number of the correct conclusion is.
6 Fuwa discuss and learn the following topics together:
Refer to the discussion of Fuwa below. Please solve this problem. The answer you chose is ().
Beibei: I noticed that when
When.
Jingjing: I found that the image is correct.
Call axis.
Huanhuan: I can see that.
Yingying: I think the key is to judge symbols.
Nini: You can take a special value.
7 In a square, a point on the side is circumscribed by a semicircle with a center and a radius and an arc with a center and a radius, and its value is ().
A.B. C. D。
8 The image of a function is shown in the figure, and the following conclusions are given:
① When, the function value is the largest;
② If, the function decreases with the increase;
③ Existence, when the function value is 0.
The correct conclusion is () a.12b.13c.23d.123.
9. The image of the function in the same rectangular coordinate system is roughly ()
10 as shown in the figure, there is a fan-shaped AOB with an area of, radius OA= on the horizontal ground, and OA is perpendicular to the ground. Without sliding, roll the fan to the right until OB is vertical to the ground, and the moving distance of point O is () A, B, C, D,
1 1 If there are three squares with side lengths respectively in Rt△ABC, the relationship is ().
A, B, C, D,
12 Eid al-Adha, six friends sat around the round table evenly for the festival. The radius of the round table is 60 cm, and the distance from each person to the round table is 10 cm. Now, two more guests come, each moving back the same distance, and then adjusting the position left and right, so that all eight people sit down. The distance between eight people is the same as the original distance between six people (that is, the distance between two people on the circumference).
A.
B.
C.
D.
13 As shown in the figure, two squares are adjacent and a semicircle is connected inside. If the area of the small square is 16cm2,
The radius of the semicircle is ().
A. 9 cm long and 9 cm wide
14, as shown in the figure, is the quartering point, and the moving point starts from the center of the circle and moves at a constant speed along the route. Let the exercise time be (s). Then, the most appropriate functional relationship between the expression and in the following image is ().
15 As shown in the figure, a positive film with a side length is connected with a side length.
The radius of the inscribed circle is.
16 As shown in the figure, the radius ⊙O is 2, the coordinate of point A is (2), and the tangent of straight line AB is ⊙O,
B is the tangent point. So the coordinates of point B are
A.B. C. D。
17 As shown in the figure, a regular triangle with a side length of 1 turns over 2008 times in the positive direction of the axis, and the points fall on the positions of the points in turn, so the abscissa of the points is.
18 As shown in Figure ①,,, are the centers of four equal circles, and A, B, C and D are the tangents. Please draw a straight line in the picture, divide these four circles into two parts with equal area, and explain that the two points that this straight line passes through are; As shown in Figure 2,,,,, are the centers of five equal circles, and A, B, C, D and E are the tangent points. Please draw a straight line in the picture, divide these five circles into two parts with equal areas, and explain that the two points that this straight line passes through are.
19' s research team observed and recorded the growth of three kinds of microorganisms attached to the surface of the object (members of the research team marked them as 1, 2, 3 respectively). These three kinds of microorganisms split into two kinds on the first day, producing new microorganisms (labeled as 4, 5, 6, 7, 8 and 9 respectively), and then change according to this law every day, that is,
A. Day 3 B. Day 4 C. Day 5 D. Day 6
20 As shown in the figure, AB is the diameter ⊙O, AD = DE, AE and BD intersect at point C, then the angle equal to ∠BCE in the figure is
a . 2b . 3c . 4d . 5
2 1. There is a container with water inlet and outlet pipes, and the amount of water in and out per unit time.
Everything is certain. Suppose that water only enters the container within 5 minutes from a certain moment, leaves the container within the next 2 minutes, and leaves the container within the next 15 minutes, just filling the container. It is known that the functional relationship between the rise of water volume y in the container and time x minutes is shown in the figure. At the 7th minute, the volume of water in the container rises. A. 15 b。
2 1. As shown in the figure, ⊙O 1 and ⊙O2 are inscribed at point P, and the connecting line intersects with ⊙O 1 and ⊙O2 at point A and point B respectively, and the straight line passing through point P intersects with ⊙O 1. , AB=2, then CD=
1。
22. As shown in the figure, the symmetry axis of parabola y=ax2+bx+c is x=- 1, which intersects with X axis at points A and B, and intersects with Y axis at point C, and OB=OC.
Then the correct number of the following conclusions is.1b = 2a2a-b+c >; - 1③0 & lt； B2-4ac & lt； 4 ④ac+ 1=b
1。
23. Known: As shown in the figure, ∠ACB=90? , ⊙O with diameter of AC intersects AB at point D, and the tangent of ⊙O intersects BC at point E and EF intersects AB at point F,
Even if OE crosses DC to P, the following conclusions are drawn: Among them, the correct ones are.
①BC = 2DE； ②OE∨AB； ③DE = PD； ④AC？ DF=DE？ CD.
A.①②③ B.①③④ C.①②④ D.①②③④
It is known that as shown in the figure, the straight line MN cuts ⊙O at point C, and AB is the diameter of ⊙O,
Extend the BA intersection line MN to points M, AE⊥MN, BF⊥MN, E, F.
They are vertical feet, BF intersection in G ⊙O, connecting AC and BC, and intersection C.
CD⊥AB, d is a vertical foot, connecting OC and CG.
The following conclusions: Among them, the correct ones are.
①CD = CF = CE； ②EF2=4AE？ BF；
③AD？ DB=FG？ FB； ④MC？ CF=MA？ BF。
A.①②③ B.②③④ C.①③④ D.①②③④
As shown in the figure, m is a point on ⊙O, and ⊙M and ⊙O intersect at a,
At two points B, P is any point on ⊙O, and straight lines PA and PB intersect respectively.
C and d ⊙M, e and f ⊙O straight CD, even number
Conclusion PE, PF, BC, the following conclusions: Among them, the correct ones are.
①PE = PF； ②PE2=PA？ PC； ③EA？ EB=EC？ ED；
④ (where r and r are the radii of ⊙O and ⊙M respectively).
A.①②③ B.①②④ C.②④ D.①②③④
1 As shown in the figure, in the diamond,,, will be a diamond.
Rotate clockwise around the point, and the graph is represented as,,,
The area of the enclosed shadow part is.
1 9 2D 3B 4B 5( 1，4，5)6 C 7D 8 C 9 C 10 C 1 1 A 12 A 13C 14 C
15. 16D 2008
18 18., as shown in figure ① (hint: the answer is not unique, any straight line passing through the intersection o can divide four circles into two parts with equal areas);
(hint: the answer is not unique, such as,,, etc. ).
19 degrees Celsius
20 days 25