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The length, width and height of a cuboid are 12.5 cm, 8 cm and 3 cm respectively. In this cuboid, what is the sum of the areas of the largest two?
Area of length * width: 12.5 * 8 = 100 (CM & # 178;)
Area of two length * width: 100 * 2 = 200 (CM & # 178;)
A cuboid container 12 cm long, 10 cm wide and 6 cm high is filled with water. The water depth is 4 cm. A round container with a bottom area of 50.24 square cm and a height of 8 cm is placed in the container
Place the small rod of the cylinder vertically so that the bottom of the rod coincides with the bottom of the container. Is the water overflowing? If so, how much? (urgent!)
2x12x10 = 240 50.24x6 = 301.44 301.44-240 = 61.44 overflow 61.44 square centimeter
What's the difference between the center and the center of gravity of a triangle
Center of gravity: the intersection of the three middle lines, the intersection of the three middle lines of the triangle at a point, the distance from this point to the vertex is twice the distance from it to the midpoint of the opposite side; perpendicularity: the intersection of the three heights of the triangle; inner: the intersection of the bisectors of the three inner angles, which is the abbreviation of the center of the inscribed circle of the triangle; outer center: the intersection of the three middle vertical lines; inner: the intersection of the bisectors of the three inner angles; Side center: the intersection of an inner bisector and other two outer bisectors. (there are three). It is the abbreviation of the center of the circumscribed circle of a triangle. If and only if the triangle is an equilateral triangle, the center of an equilateral triangle consists of four centers
Let's go
Given that a is a nonnegative real number, the inequality AX2 - (a + 1) x + 1 about X is solved
When a = 0, the original inequality is - x + 1 < 0, and the solution set of the original inequality is (1, + ∞) (2 points) (II) when a ＞ 0, the inequality is transformed into (x-1) (AX-1) ＜ 0, and the inequality corresponds to two parts of the equation (x-1) (AX-1) = 0
What does DF (x) = f (x) DX mean?
In particular, what does DF (x) mean
F (x) means the slope of F (x)
DX is a process in which X tends to zero infinitely
DF (x) is an infinitesimal increment with DX
When △ ABC.AB=c , BC = a, AC = B, ∠ B = 90 degree. ∠ a = 30 degree. ∠ C = 60 degree?
In RT △ ABC, ab = C, BC = a, AC = B, ∠ B = 90 degree. ∠ a = 30 degree. ∠ C = 60 degree. Make a symmetrical triangle of △ ABC with C side. Get △ abd. Prove whether △ ACD is isosceles triangle? Why is it contradictory with Pythagorean law?
The △ ACD is an isosceles triangle, AC = ad, C = D = 60 degree, CBD = 60 degree, which is an equilateral triangle
I don't know what you mean by contradiction, but I remind you:
Pythagorean theorem can only be used for right triangle!
Y = e ^ x ^ 2cos2x differential
To find the differential of a function,
The general expression of n-order derivative of y = (x ^ 2-2) / (x ^ 2-x-2)
Y = (x ^ 2-2) / (x ^ 2-x-2) = 1 + X / (x ^ 2-x-2) = 1 + X / (X-2) (x + 1) = 1 + 2 / (X-2) + 1 / (x + 1) = 1 + 2 (X-2) ^ (- 1) + (x + 1) ^ (- 1) y '= - 2 (X-2) ^ (- 2) - (x + 1) ^ (- 2) y' '= 4 (X-2) ^ (- 3) + 2 (x + 1) ^ (- 3) y' '= - 12 (X-2) ^ (- 4) - 6 (x + 1) ^ (- 4) in general, the n-order derivative of y = (- 1) ^ n *
If you add the same number to the numerator and denominator of one thirteenth, it can be divided into about one fifth. What is the number added
Let X be added
（1+x）/（13+x）=1/5
The solution is x = 2
Little girl is very bad at math. She is preparing for the make-up exam of advanced mathematics~
1. Find the general solution of the following separable variable differential equation XY '- yiny = 0
2 find the general solution of the following homogeneous equation XY '- Y - (Y & sup2; - X & sup2;) & frac12
1 / x = 1 / (y * LNY)
LNX = ln (LNY) + lnc
It is concluded that x = clny is the power of Cx of y = E
What about the two equal sign?
In the form of (Y / x)
Let u = Y / x, so x * Du / DX + U = dy / DX
Just take it in and separate the variables
RELATED INFORMATIONS
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- 2. A cuboid glass can is 12 cm long, 8 cm wide and 5 cm high. When it is placed horizontally, the water depth is 3 cm. When it is placed vertically, how many cm is the water depth?
- 3. The newly built teaching building needs 150 cuboid drainage pipes with a length of 3 meters, a width of 1 decimeter and a height of 8 cm. The surface of the drainage pipe is a layer of iron sheet, which needs iron sheet How many square meters?
- 4. A piece of 8 cm long and 6 decimeter wide rectangular iron sheet is rolled into a cuboid with a square bottom. What is the maximum volume of this cuboid?
- 5. In order to measure the volume of a potato, Xiao Ming carried out an experiment according to the following steps: (1) put a certain amount of water into a cylindrical glass with a bottom diameter of 12 cm, and the height of the water surface is 7 cm; (2) put the potato into the water, and then measure the height of the water surface is 8 cm. If the thickness of the glass is ignored, what is the volume of the potato Centimeter? (the number obtained keeps the whole number)
- 6. In order to measure the volume of potatoes, Xiao Ming carried out an experiment as follows: Put a certain amount of water into a cylindrical glass with a bottom diameter of 8 cm, and the height of the water surface is 6 cm. Put the potato into the water, and then measure the height of the water surface again, which is 10 cm. If the thickness of the glass is ignored, how many cubic centimeters is the volume of the potato?
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- 9. A rectangular iron block with a length of 10 cm, a width of 8 cm and a height of 7.85 cm is fused into a cylinder with a diameter of 8 cm at the bottom What is the height of this cylinder?
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- 13. A cuboid glass container is 20dm long and 15dm wide. The water depth in the container is 3.8dm Ask for guidance
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- 17. Fill a 15 cm square glass fish tank with water, then pour the water into a 20 cm long, 15 cm wide and 12 cm high rectangular tank
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