![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
Differential of composite function Known F[w*(1+t)]=K(w) Differential equation on both sides Why do you get it F'(dw + w*dt)=K' dw
In books or other people's articles?
I can only say that it's not good to write like this, especially in F '
It should be written clearly and not omitted at will
F'(w(1+t)) * (dw+w*dt) = K'(w) dw
Is that ok
Differentiation of compound function
Y = sin (2x + 1), find dy y = sin u, u = 2x + 1, according to the formula, Dy = f '(U) g' (x) DX, the result is, 2cos (2x + 1) DX if you use the formula dy = f '(U) Du: dy = D (sinu) = cos u Du = cos (2x + 1) d (2x + 1) = cos (2x + 1) 2DX = 2cos (2x + 1) DX, how can cos (2x + 1) 2DX be obtained after the second equal sign? Cos (2x + 1) d (2x + 1) = cos (2x + 1) 2xD + cos (2x + 1) d is not it? Why is it equal to cos (2x + 1) 2DX? Where is the following? (q.q)
First of all, you need to understand that D is a differential operator, which has indicated a kind of operation. The meaning of COS (2x + 1) d (2x + 1) is the differential of COS (2x + 1) multiplied by 2x + 1 to x, not the differential of COS (2x + 1) d (2x + 1). If you calculate the differential as a whole, the mistake is here, This is the simplest differential, and then add the preceding one, cos (2x + 1) 2DX
The ratio of the three numbers of a, B and C is 1:2:3. If the average is 30, what are the numbers of a, B and C?
30×3÷（1+2+3）=15
A: 15 × 1 = 15
B: 15 × 2 = 30
C: 15 × 3 = 45
Given that the sum of the two sides of a right triangle is 2, what is the maximum area of the triangle?
The maximum area is 1 / 2 when both sides are 1
Let two sides be a and B respectively
A + B = 2, find the maximum value of AB / 2
Because B = 2-A, then AB / 2 = a (2-A) / 2 = - (A & # 178; - 2A) / 2 = - (A-1) &# 178 / 2 + 1 / 2
The maximum area is 1 / 2 when a = 1
The average number of a, B and C is 120. The average number of B and C is 90. What's the number of a
You don't have to have an answer
The sum of numbers a, B and C is 120 times 3 = 360
The sum of the two numbers is 90 times 2 = 180
A, B, C - B, C = 360-180 = 180
So the number a is 180
Let AX = B have solutions α 1 = (1,2,3), α 2 = (- 1,2,3), and R (a) = 2, then the general solution of AX = B is________ .
Let AX = B have solutions, α 1 = (1,2,3) ^ t, α 2 = (- 1,2,3) ^ t, and R (a) = 2, then the general solution of AX = B is________ .
A1-a2 is a fundamental solution
So the general solution is K (A1 - A2) + A1
Party A and Party B process 1500 parts respectively. Because Party B adopts new technology, the number of parts processed by Party B is three times that of Party A at the same time. Therefore, Party B processes less than 20 hours than Party A. how many parts do they process each hour?
Let a process x per hour, then B process 3x per hour. According to the meaning of the problem, 1500x = 15003x + 20, the solution is x = 50. Test: when x = 50, 3x = 3 × 50 ≠ 0, so x = 50 is the root of the original fractional equation, and conforms to the meaning of the problem. Answer: a processes 50 per hour, B processes 150 per hour
7x+5(20-x)=180
7x+5(20-x)=180
7x+100-5x=180
2x+100=180
2x=180-100
2x=80
x=40
Inspection:
7x + 5 (20-x) = 7 times 40 + 5 times 20 minus 40 = 280 + 5 times 20-5 times 40 = 280 + 100-200 = 380-200 = 180
The left equals 180, and the right equals 180
So x = 40
See?
It's my pleasure to answer your questions
If you don't understand this question, you can ask,
make progress every day.
There are 14 million kg grain in the three warehouses. The grain quality ratio of warehouse A and warehouse B is 3:4, and that of warehouse B and warehouse C is 6:7
There are 14 million kilograms of grain in the three warehouses. The grain quality ratio of warehouse A and warehouse B is 3:4, and the grain quality ratio of warehouse B and warehouse C is 6:7. Each of the three warehouses has 10000 kilograms less grain? One parent's help,
A: B: C = 9:12:14
1400÷(9+12+14)=40
A = 9 × 40 = 3.6 million kg
B = 12 × 40 = 4.8 million kg
C = 14 × 40 = 5.6 million kg
The sum of three fourths of a number plus five is equal to the difference of two times of it minus nine. Let a number be x, and the equation is []
3/4X+5=2X-9
14=5/4X
X=56/5
RELATED INFORMATIONS
- 1. It is proved that if the function f (x) satisfies the relation f '(x) = f (x) and f (0) = 1 in (- ∞, + ∞), then f (x) = e ^ X
- 2. Ask questions about higher numbers 3 (about differential mean value theorem) Let B not be equal to a, and prove that | arctanb arctana | is less than or equal to | b-a|
- 3. Some problems in "differential mean value theorem and derivative application" of higher numbers 1. Let f (x) be continuous on [0,1], derivable in (0,1), and f (0) = f (1) = 0, f (1 / 2) = 1 / 2. It is proved that for any C ∈ (0,1), there exists ξ∈ (0,1) such that f '(ξ) = C 2. It is known that f (x) is differentiable in R, and (x →∞) Lim f '(x) = E, (x→∞)lim [(x+c)/(x-c)]=(x→∞)lim [f(x)-f(x-1)] Finding the value of C
- 4. Let a > 0, b > 0, prove that (x + a) 2 (X-B) + x2 = 0 has one positive root and two negative roots (zero point theorem and intermediate value theorem of higher numbers)
- 5. Zero point theorem and intermediate value theorem
- 6. The difference between the function differentiable in the closed interval and the function differentiable in the closed interval, why is the mean value theorem only required to be differentiable in the open interval? Why do mean value theorems only require derivability in open intervals? Closed interval is continuous, open interval is differentiable, so closed interval is differentiable? Explain why... I need a reason
- 7. The relationship between Lagrange's mean value theorem and Rolle's theorem
- 8. Rolle's theorem, Lagrange's mean value theorem and Cauchy's mean value theorem are generally applied to what questions?
- 9. Continuity of functions in higher numbers Discuss the continuity of the following functions and draw the f (x) graph 1. F (x) = LIM (n approaches infinity) 1 (1 + (cosx) ^ 2n) 2. F (x) = LIM (n approaches infinity) {[1-x ^ (2n)] \ [1 + x ^ (2n)]} * x Graphic words, a little description of what it looks like
- 10. The continuity of higher number function (concrete process) f(X)=1/xsinx,(x0) When we ask what the constant k is, f (x) is continuous in its domain?
- 11. There is a pile of yellow sand on the construction site. One quarter of the total amount was used in the first day, and one quarter more was used in the second day than in the first day. How many tons of yellow sand are left
- 12. 4 / 5 of a is equal to 2 / 3 of B, and a is a fraction of B
- 13. There are five consecutive even numbers, and their sum is 130. What are the five even numbers?
- 14. The distance between a and B is 40 km, the speed of motorcycle is 45 km / h, the speed of truck is 35 km / h, and the speed of truck is 35 km / h How long does it take for the same car to travel in opposite directions? The distance between the two cars is 10 kilometers?
- 15. It is known that a * 6 / 5 = 9 / 10 * b = 13 / 13 * C, and ABC is not equal to 0. Try to arrange ABC in the order of% d% a
- 16. It takes Xiaogang 4 minutes, Xiaoming 6 minutes and Xiaojuan 8 minutes to run a circle along the track. How many minutes will we meet at the starting point
- 17. What are the seven basic units of the international system of units
- 18. When will all the work done by Ampere force be converted into Joule heat, when will part of it be converted into kinetic energy and part into Joule heat, Included in the magnetic field and electromagnetic induction
- 19. When the resistance of the conductor remains unchanged, the current flowing through the conductor will increase from 1.5A if the voltage at both ends of the conductor is increased from 4V to 6V A. To 3.5A B. to 2-25a C. to 0.75a D. to 7.5A
- 20. What is the relationship among electric power, voltage and current in series circuit? What is the relationship among electric power, voltage and current in parallel circuit