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A 40 cm long, 30 cm wide rectangular iron sheet, four corners minus a side length of 5 cm square, make a 5 cm deep uncovered rectangular iron box What's the volume of this iron box The thickness of iron sheet is not included
The length of the cuboid is 40-5-5 = 30
The width of the cuboid is 30-5-5 = 20
The shape of the cuboid is 5 cm
Volume: 30 × 20 × 5 = 3000 cubic centimeter
There is a rectangular sheet of iron 40cm in length and 20cm in width. Please use it to make a 5cm deep rectangular uncovered sheet iron box (the larger the volume, the better),
What is the maximum volume of Dragon Ridge
1. When the length is twice the width, there are three spellings
The first one is to cut 5cm small squares from four corners to form a cuboid with length of 30cm, width of 10cm and height of 5cm. The volume of this method is the smallest. 30 × 10 × 5 = 1500 (CM & # 179;)
The second method is to divide one side of the rectangle into four equal parts. Cut out two small squares (one at the top and one at the bottom) with the side length of 5cm, and move the two small squares to the opposite width. Corresponding to the left one, you can make a cuboid with the length of 40-5 = 35 (CM), the width of 20-10 = 10 (CM), and the height of 5cm. At this time, the volume is 35 × 10 × 5 = 1750 (CM & # 179;)
The third method: divide the rectangle 40cm in length into eight equal parts, that is, divide it into eight small rectangles 5cm in length and 20cm in width, take down two small rectangles 5cm in length and 20cm in width, and leave six small rectangles, and then move the two small rectangles to the middle of the remaining 30cm in length, leaving 5cm on both sides of 30cm, In this way, we can put together a cuboid: 20cm in length, 20cm in width and 5cm in height. At this time, the largest volume is: 20 × 20 × 5 = 2000 (CM & # 179;)
There is a rectangular iron sheet, 40cm long and 20cm wide, which can be cut and connected into a 5cm deep uncovered rectangular box
1. Please draw a suitable cutting diagram and calculate the volume of this uncovered cuboid box
2. Now we want to cut and connect this sheet of iron into a rectangular box with the largest volume. Please draw a cutting diagram and calculate its volume
Divide the sheet iron into two parts, and then cut half of them into four sheets of 20 long and 5 high. The volume is 20 * 20 * 5 = 2000
Let a (1,1) (3,5) (4,7) be known, and prove that a, B and C are collinear
Just calculate the slope between AB and BC, ab (5-1) / (3-1) = 2, BC (7-5) / (4-3) = 2, so it's on a straight line
In trapezoidal ABCD, ad is parallel to BC, ad: BC = 1:2, diagonal AC and BD intersect with O, s triangle AOD = 6, then the area of trapezoidal ABCD is -?
Triangle AOD and triangle BOC are similar triangles, then triangle BOC area is 24, triangle ABO and triangle AOD are the same height, bottom Bo: od = 2:1, so triangle ABO area is 12, similarly triangle doc area is 12, total: 54
y=x^(1-lgx) (1
Y = x ^ (1-lgx) take the logarithm of base 10 at the same time
lgy=(1-lgx)*lgx
=-（lgx-1/2）^2+1/4
one
A bamboo pole is several meters long, and it is 1.8 meters longer with a rope. If the rope is folded in half and then measured again, it is 1.2 meters shorter. How long is the rope?
(1.2 + 1.8) × 2 = 3 × 2, = 6 (m)
Given a-b-4ab = 0, find the value of 2a-2b + 3AB / a-b-5b
Whether "2a-2b + 3AB / a-b-5b" is "2a-2b + 3AB / a-b-5b"
∵A-B-4AB=0
∴A-B=4AB
∴2A-2B+3AB/A-B-5AB
=2(A-B)+3AB/(A-B)-5AB
=8AB+3AB/4AB-5AB
=11AB/-AB
=-11
If the three sides of a triangle wheat field are 9m, 12m and 15m respectively, the area of this wheat field is______ ㎡．
∵ 92 + 122 = 152, ∵ three triangles with lengths of 9m, 12m and 15m form a right triangle, of which the right side is 9m and 12M, ∵ the area of the triangle is 12 × 9 × 12 = 54m2
Log (1 / a) B + logab simplification
Original formula = log (1 / a) + logb + laga + logb
=-loga+logb+loga+logb
=2logb
RELATED INFORMATIONS
- 1. Make a 5cm deep uncovered rectangular iron box with a 40cm long and 20cm wide rectangular iron sheet. What is the maximum volume of this iron box
- 2. The volume of a cuboid is 192 square centimeters, the bottom is a square with side length of 8 centimeters, and the surface area of the cuboid is ()
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- 9. Now there is an empty cuboid container a and a cuboid container B filled with water 24 cm deep. Pour part of the water in container B to a (supplement, bottom) Now there is an empty cuboid container a and a cuboid container B with 24 cm deep water. We need to pour part of the water in container B to container a, so that the water in the two containers is the same height. At this time, how many cm deep is container a? Urgent, want to segment formula, hope to have enthusiastic netizens to help (Note: container a is 40cm long, 20cm high and 30cm wide. Container B is 30cm long, 24cm high and 20cm wide.)
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- 11. There is a rectangular sheet of iron 40 cm in length and 30 cm in width. Cut out an equal small square at its four corners to make a cuboid uncovered sheet iron box 5 cm in depth (the thickness of welding joint is not included). What is the volume of the box?
- 12. A cuboid iron box without a cover, 18 cm long, 15 cm wide and 10 cm high. How much iron sheet does it need to make this iron box
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- 15. A cuboid uncovered iron water tank is 0.8 meters long, 0.65 meters wide and 0.6 meters high. How many square meters of iron is needed to make this water tank? If each liter of water weighs 1 kg, how many kg of water can the tank hold at most? (the thickness of iron sheet is ignored)
- 16. A 24 cm long and 8 cm wide rectangular sheet iron, can you cut it into 5 pieces and weld it into a cuboid container with a cube at the bottom? Draw a picture of the scissors. What's the volume of the container?
- 17. A 24 cm long rectangular sheet iron is cut off from the four corners and welded into a box. The volume of the box is 486 cubic centimeters, and the original width of the sheet iron is calculated
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