In the transmission line theory, how do circuit theory and field theory connect

In the transmission line theory, how do circuit theory and field theory connect

With reference to the

If the rental of a 45 seat bus is 250 yuan per vehicle and that of a 60 seat bus is 300 yuan per vehicle, which is the best way to rent

Suppose the total number of people is x and the number of 45 passenger cars is a, then there are: X / 45 = a, x = 45A (x + 15) / 60 = A-1, x = 60 (A-1) - 15 = 45A, so: a = 5 (45 passenger cars) x = 45A = 225 (people) rent 5 45 passenger cars, the cost is 250 × 5 = 1250 yuan, rent 4 60 passenger cars, the cost is 300 × 4 = 1200 yuan, more

How many tiles do you need to lay on a house that is 5 meters long and 4 meters wide

5 × 4 = 20 square meters = 2000 square decimeters
2000 △ 20 = 100 pieces
It will cost at least 100 yuan

Finding the second order inverse matrix
2,3
4,5
The inverse of the matrix

Inverse matrix = 1 / (- 2)
（5 -3
-4 2）

He knew that the length of each rail was 25m. He began to count the number of times he heard the impact sound (from the joint of wheel and rail) from 0. It took 30s to count to 15 times. Due to inattention, the number of times he heard the impact sound in the next 20s was not clear, But he counted the number of impact sound in the sixth 10s to 13, assuming that the train was moving in a straight line with uniform acceleration in the 60s. Based on the above measured data, he estimated the acceleration

If the starting speed is V and the acceleration is a, the displacement within 30s is 15 * 25m
So 15 * 25 = V * 30 + A * 900 / 2 ------ (1)
If the velocity is V + 50 * a in 50s and the displacement of R is 13 * 25m in the sixth 10s, then
13*25=（V+50*a）*10+a*100/2 ————————（2）
It can be concluded from the above two formulas
a=6m/s^2

When x tends to 0, find the limit (1 / x) ^ 2 - (Cotx) ^ 2

=lim (1/x)^2-(1/tan x)^2
=lim (x^2 - tan^2 x) /(x^2 · tan^2 x)
=LIM (x ^ 2 - Tan ^ 2 x) / (x ^ 4) [Equivalent Infinitesimal Substitution]
=LIM (2x - 2 Tan X / cos & # 178; x) / (4x ^ 3) [lobida's Law]
=lim (1/cos^3 x) ·lim (x·cos^3 x - sin x) /(2x^3)
=1. LIM (COS ^ 3 x - 3 x · cos ^ 3 x · SiN x - cos x) / (6x ^ 2) [lobida rule]
=lim (cos x) ·lim [(cos^2 x - 1 ) - 3 x·cos^2 x·sin x] /(6x^2)
=1·lim [ -sin^2 x - 3 x·cos^2 x·sin x] /(6x^2)
= -lim sinx·[ sin x + 3 x·cos^2 x] /(6x^2)
=- Lim x · [SiN x + 3 x · cos ^ 2 x] / (6x ^ 2) [Equivalent Infinitesimal Substitution]
= -lim [ sin x + 3 x·cos^2 x] /(6x)
=- Lim [cos x + 3 (COS ^ 2 x - 2 · x · cosx · SiNx)] / 6 [lobida's Law]
= -[ 1 + 3 (1 -2×0) ] /6
= -2/3

If the power of 2A + B-4 of equation 2x plus the power of 3a-2b-3 of 4Y is equal to 1, it is a bivariate linear equation about X and Y. what are the values of a and B?

There are two situations from the meaning of the title
(1).2a+b-4=2,3a-2b-3=1
A = 16 / 7, B = 10 / 7
(2).2a+b-4=1,3a-2b-3=2
a=15/7,b=5/7

Start to be yourself from today on

From now on, be yourself.

How much is one point equal to

1 point = 0.01 yuan

(1+1/2)X(1+1/3)X(1+1/4)X(1+1/5)X.X(1+1/1999)X(1+1/2000)
Simple calculation

(3/2)(4/3)(5/4)…… (2000/1999)(2001/2000)=2001/2
Simplify each other, you can see it by yourself!