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My mother put some potatoes in a cylindrical container with a bottom area of 40 square centimeters to clean. At this time, the water depth in the container was 30 cm. After taking out the potatoes, the water dropped by 3 cm. What was the volume of these potatoes______ Cubic centimeter
40 × 3 = 120 (cubic centimeter). A: the volume of these potatoes is 120 cubic centimeter
A cuboid container 24 cm long, 18 cm wide and 15 cm high is filled with water. Pour all the water in the container into a container 12 cm long and wide. How high is the water surface
24 * 18 * 15 / (12 * 12) = 45 (CM)
Pour 7 cm deep water into a square container with 20 cm long edges, and put a rectangular iron block with 15 cm long, 10 cm wide and 5 cm high
How many centimeters does the water surface rise when it is placed flat in the container with one side close to the bottom of the container
1、 At 5, the volume of water rising is equal to the volume of iron
（15*10*5）/（20*20）=1.875
2、 When I10 is high
20 * 20-15 * 5) * (10-7) = 325 * 3 = 975 > 750
（750/20*20-15*5）=750/125=6
3、 When 15 is the highest
15*10*5/（20*20-10*5）=750/150=5
1. In a cuboid container with a length of 25 decimeters and a width of 20 decimeters, there is water 30 decimeters deep. Now a cube iron block with a length of 10 decimeters is sunk in the water
Water level rise: 10 × 10 × 10 ÷ (25 × 20) = 2 (decimeter)
If the area of an isosceles triangle is 1cm ^ 2 and the waist length is 2cm, the degree of vertex angle is 0
△=(1/2)bcsinA
1=1/2(2*2*sinA)
1/2=sinA
A = 30 ° or 150 degree
When t = 0, a sinusoidal AC voltage is - 220 V, and its initial phase is - 45 °. What are its maximum and effective values?
314
two hundred and twenty
The known complete set is u, a = {1, 3, 6, 7}, CUA = {2, 4, 5, 8, 9}, Cub = {4, 6, 9}. Find: (1) complete set u; (2) set B; (3) Cu (a ∩ b)
（1）∵A={1，3，6，7}，CUA={2，4，5，8，9}，A∪CUA=U∴U={1，2，3，4，5，6，7，8，9}（2）∵U={1，2，3，4，5，6，7，8，9}，CUB={4，6，9}．∴B={1，2，3，5，7，8}（3）∵A={1，3，6，7}，B={1，2，3，5，7，8...
Given the line segment CD, extend CD to point B, make DB = CD, extend DC to point a, make CA = CB (unfinished)
If AB = 12cm, find the length of CD
Let CD be xcm
Then DB = x
Then CB = CD + DB = 2x
Then CA = CB = 2x
Then AB = AC + CB = 4x = 12
X = 3 is CD = 3
A. B is a square matrix of order n, and R (a) = R (b). It is proved that there exists an invertible matrix m such that AMB = o
False. Counterexample: a = b = identity matrix. Of course, R (a) = R (b). Any invertible matrix M: AMB = m ≠ 0
Given 2x + 8y – xy = 0, how to find the minimum value of X + y with basic inequality
X + y = 1 / 2 * (X-6) * y is obtained from 2x + 8y – xy = 0
RELATED INFORMATIONS
- 1. In a rectangular container 20 decimeters long and 15 decimeters wide, there is water 20 decimeters deep. Now a cube iron block is sunk in the water, and the water surface rises 09 decimeters. What's the volume of this cube iron? 2. There are three cube iron blocks, their surface areas are 24 square centimeters, 54 square centimeters and 294 square centimeters respectively. Now dissolve the three iron blocks into a big cube, and find the area of the big cube
- 2. In a cuboid water tank of 15 decimeters long and 12 decimeters wide, there is 10 decimeters deep water. If a square iron block with 2 decimeters long edge is sunk in the water, then How high is the water in the tank now?
- 3. In a square water tank with 20 cm edge length (measured from the inside) filled with water, there is a 16 cm long, 10 cm wide rectangular iron block When the iron is taken out, the water in the water tank drops by 2cm. What is the height of the iron?
- 4. In a square water tank full of water with 20 cm long edges, there is a rectangular iron block immersed in water, which is 10 cm long and 8 cm wide. When the iron block is taken out, the water level drops by 2 cm. What is the height of this rectangular iron block?
- 5. In a cuboid basin with a length of CM, a width of CM, and a depth of CM, the water depth is 20 cm. If you put a cube stone with an edge length of 10 cm in the basin, it will be very difficult How many centimeters will basin reed water go up? It is 50 cm long 40 cm wide 30 cm deep
- 6. The edge of a cube glass container is 2 decimeters long. Pour 5.5 liters of water into the container, and then put a stone into the water. At this time, the water depth in the container is 15 cm What's the volume of stone in cubic centimeter
- 7. In a 12 cm long, 9 cm wide, 8 cm high cuboid container filled with water, the water soaked with a 6 cm long square iron block, when the iron block from the water After taking out, what will happen and what will the result be
- 8. A rectangular glass container, 8 decimeters wide, now 45 cm deep, when a square iron block with an edge length of 4 decimeters is placed in the water After that, will the water overflow? If so, how many liters?
- 9. How many centimeters can the water surface rise to when a cuboid tank with a length of 50 cm, a width of 40 cm and a height of 30 cm is filled with water 20 cm deep and a cube with a length of 20 cm is immersed in water?
- 10. A cuboid water tank is immersed in a cube iron block with an edge length of 10 cm. The length of the water tank is 40 cm, the width is 30 cm, and the water depth is 25 cm. When the iron block is taken out, what is the distance between the water surface and the bottom of the tank?
- 11. A. The bottom area ratio of two cylindrical containers B is 4:3. The water depth of container a is 20 cm, and that of container B is 10 cm. Now, the same amount of water is injected into the two containers to make the water depth of the containers equal. At this time, the water depth of container a is 20 cm, and that of container B is 10 cm______ Cm
- 12. A and B are two cuboid containers. Container a is 40 cm long, 30 cm wide and 24 cm high. Container B is 20 cm long, 20 cm wide and 36 cm deep. Pour the water in container B into container a until the water depth in the two containers is the same. How many mm is the water depth in both containers?
- 13. The length, width and height of a cuboid container are 60cm, 40cm and 30cm respectively. The original height of the water surface is 25cm. After putting it into a cuboid container The length, width and height of a cuboid container are 60cm, 40cm and 30cm respectively. The original height of the water surface is 25cm. After putting in a cuboid iron block, all the iron blocks are submerged in the water, and the height of the water surface rises to 28cm. The length of the iron block is 20cm, the width is 15cm, and how many centimeters are behind the iron block?
- 14. There is an empty cuboid container a 40 cm long, 30 cm wide and 20 cm high. There is another cuboid container B 30 cm long, 20 cm wide and 24 cm deep. Now pour part of B's total water to a so that the water in the two containers is the same height. How many cm deep is the container
- 15. Use three cuboids that are 3cm long, 2cm wide and 1cm high to form a large cuboid with the smallest surface area. How many square centimeters is the surface area of this cuboid
- 16. The circumference of the bottom of the cuboid is 36 cm and the height is 8 cm. The total length of the edges of the cuboid is () cm
- 17. The circumference of the bottom of a cuboid is 36 cm, and the height is 8 cm. What is the total length of the edges of the cuboid?
- 18. A cuboid is 8 cm in height, 1 / 2 in width and 5 / 4 in width. The cuboid is () cm in width, () cm in length, () cm in edge length, () m3 in volume and () cm2 in surface area
- 19. A cube lead block with an edge length of 8 cm is installed in a cuboid glass tank of 16 cm long, 10 cm wide and 20 cm high, and then some water is put into the tank to completely submerge the cube lead block. When the lead block is taken out of the tank, how many cm will the water in the tank drop?
- 20. In a cylindrical glass tank with a bottom radius of 10 cm and a water depth of 8 cm, an iron block of 8 cm in length and width and 15 cm in height should be placed in the tank 1. How many centimeters will the water surface rise when the iron block is placed horizontally in the water? 2. Put the iron block in the water vertically, how many centimeters will the water rise?