9.8 times 25 is simple!

9.8 times 25 is simple!

9.8 times 25
=(10-0.2)×25
=10×25-0.2×25
=250-5
=245

How to solve dy / DX = y (1-y / 10)

∵ dy / DX = y (1-y / 10) = = > (1-y / 10) dy / y = DX = = > (1 / Y-1 / 10) dy = DX = = > ln ∵ y ∵ Y / 10 = x + ln ∵ C (C is an integral constant)

The water cement ratio of hollow anchor grouting is 0.5:1, 2.26 cubic meters of cement slurry per linear meter, how to calculate the amount of cement?

The specific gravity of water is 1.0g/cm & sup3;, and the specific gravity of cement is 3.10 ~ 3.20, taking an average of 3.15g/cm & sup3;. First calculate the specific gravity of cement slurry with 0.5 water cement ratio: = (0.5 + 1) / (0.5 / 1 + 1 / 3.15) = 1.835g/cm & sup3; = 1835kg / M & sup3; thus, the cement consumption per cubic meter of cement slurry = [1 / (1 + 0.5)] x1835

Digital logic: logic expression simplification
15.F=A+BD+CDE+D= .
A.B.C.D.
18. For the logic function y = a + B + C + B, by using the substitution rule, let a = BC substitute, y = BC + B + C + B = C + B holds
A. C error
Who can tell me how to simplify and why it's wrong··
15, 18 wrong! The non number didn't come out. It couldn't be typed.
corrections:
15. F = AB (b non number) + BD + CDE + a (a non number) d=_____________
AB (b not sign) + D
18. For the logic function y = AB (b non number) + AB (a non number) + BC (b non number) + BC (C non number), by using the substitution rule, let a = BC substitute, then y = BCB (the second B non number) + BCB (BC non number) + BC (b non number) + BC (C non number) = BC (b non number) + BC (non number) holds. （ ）

Use 'to denote a non sign, such as B, which is not b
15.F=AB'+BD+CDE+A'D
=(ab '+ ab'd) + (a + a') BD + CDE + (B + B ') a'd
=(AB'+AB'D)+(ABD+A'BD)+CDE+（A'BD+A'B'D）
=AB'+CDE+(AB'D+ABD+A'BD+A'B'D）
=Ab '+ CDE + (ab' + AB + a'B + a'B ') d (formula in brackets equals 1)
=AB'+CDE+D
=Ab '+ D (using the formula a = a + AB)
eighteen
Y=AB'+A'B+B'C+BC'
=BCB'+(BC)'B+B'C+BC'
=0+(B'+C')B+B'C+BC'
=B'B+C'B+B'C+BC' (B'B=0,BC'+BC'=BC')
=B'C+BC

What is the geometric meaning of ternary function
A function of one variable represents a curve on the xoy plane,
A binary function represents a surface in XYZ space,
One variable function and two variable function have used up the number of XYZ axis (let's say so for a moment), so what's the geometric space meaning of three variable function, then four variable function, five variable function,... N-variable function

After college, if you want to draw a graph when you represent n-ary function (n > 2), you still draw a three-dimensional coordinate graph, take the function value as the z-axis, and the subspace formed by the independent variable is represented by xoy plane, A vector in this plane is n-dimensional rather than 2-dimensional. Therefore, such a graph is usually only schematic (in fact, only schematic is needed). You will see this graph when you learn the best approximation problem in functional analysis or Fourier analysis

How many kilometers per hour does the bus usually run on the highway?

The speed of regular bus is 110 km / h

How to calculate 0.48 * 99 simply

=0.48*（100-1）
=0.48*100-0.48
=48-0.48
=47.52

How much more is the surface area of a cylinder with a diameter of 10 cm and a height of 25 cm cut along its diameter and divided into figures of the same shape?

10 * 25 * 2 = 500 square centimeter

Use a 24 meter long iron wire to form a rectangle with a length to width ratio of 2:4. Then how many square meters is the area of the rectangle?

The sum of length and width is 24 / 2 = 12 meters
The length is 12 * 2 / (2 + 4) = 4m
The width is 12-4 = 8 meters
The area of this rectangle is 4 * 8 = 32 square meters

Polynomial factorization factor 2x-4x small '2 18x' 3-2xy '2

2x-4x^2
=2x(1-2x)
18x^3-2xy^2
=2x(9x^2-y^2)
=2x(3x-y)(3x+y)