When the altitude increases by 1000 meters, the temperature will decrease by 5 degrees Celsius. Now the ground temperature is 8 degrees Celsius. What is the altitude temperature of 3000 meters?

Temperature = 8-3000 △ 1000 × 3 = - 7 ° C

When the altitude rises by 1000 meters, the temperature will drop by about 6 ℃; now the temperature in a place with an altitude of 500 meters is 15 ℃. Then use X to express the altitude and y to express the temperature. Please write down the relationship between Y and X\

∵ for every 1km rise, the temperature drops by 6 degrees
The altitude is 500m and the temperature drops by 3 degrees
Y = 18-6x (x in KM)

When the altitude increases by 1000 meters, the temperature decreases by 6 degrees centigrade. When the ground temperature is 10 degrees centigrade, the temperature at the top of the mountain is - 14 degrees centigrade

1000×[10-(14)]÷6=4000
The mountain is 4000 meters high

1 / 2-2x = 1 / 3

1 / 2 - 2x = 1 / 3
2X = 1 / 2 - 1 / 3
2X = 1 / 6
X = 1 / 12

The solution set of the system X − 2Y = 32x + y = 11 is ()
A. {5，1}B. {1，5}C. {（5，1）}D. {（1，5）}

Let x − 2Y = 32x + y = 11, the above equation be denoted as ①, and the following equation be denoted as ②. From 2 × ①, we can get 2x-4y = 6 ③. From ③ + ②, we can get y = 1. Substituting y = 1 into ②, we can get x = 5. Then the solution of the equations is x = 5Y = 1

Higher mathematics to find a curve XZ = 4, y = 0 around the z-axis surface equation rotation

[under positive and negative root sign (x square + y Square)] z = 4
(x ^ 2 + y ^ 2) Z ^ 2 = 16 is the surface equation of curve XZ = 4, y = 0 rotating around Z axis
Law: around that axis, the variables corresponding to that axis remain unchanged, and then change the remaining variables into the sum of the squares of the two variables under the positive and negative root sign
This is a formula. You can find it in the textbook of space analytic geometry

The order of fractional mixed operations and ()（
The order of fractional mixing operation and ()

Integer, same

Know the function f (x) = LG (1 + 2x), f (x) = f (x) - f (- x) 1. Find the domain of F (x) 2. When 0 ≤ x < 1 / 2, there is always f (x) ≥ 1
Given the function f (x) = LG (1 + 2x), f (x) = f (x) - f (- x) 1
2. When 0 ≤ x ＜ 1 / 2, there is always f (x) ≥ M

1 + 2x > 0, x > - 1 / 2, the domain of F (x) is (- 1 / 2, + ∞), the domain of F (- x) is (- ∞, 1 / 2)
So the domain of F (x) is (- 1 / 2,1 / 2)
2.F(x)=lg(1+2x)-lg(1-2x)=lg[(1+2x)/(1-2x)]=lg{[2-(1-2x)]/(1-2x)}=lg[2/(1-2x) -1]
Thus, we can see that f (x) is an increasing function on [0,1 / 2],
If f (x) ≥ m is constant, only [f (x)] min ≥ m, X ∈ [0,1 / 2)
That is, f (0) ≥ M
m≤0

Given that x, y, Z satisfy X-Y + 5 ≥ 0 x ≤ 0 x + y + K ≥ 0, and the minimum value of Z = 2x + 4Y is - 6, then the value of constant k is___ ．

First, according to the constraint condition X-Y + 5 ≥ 0 x ≤ 0 x + y + K ≥ 0, the feasible region is drawn. Because z = 2x + 4Y, the minimum value is transformed into 14 of the intercept on the Y axis. When the line z = 2x + 4Y passes through point B, the minimum value of Z is - 6. From X-Y + 5 = 02x + 4Y = - 6, we get x = - 133Y = 23, and substitute the line x + y + k = 0 to get k = 113, so the answer is: 113

1、 4 / 3x + 3 / 2Y = 7 ① 5 / X-6 / y = 3 ②
2、 Finding the positive integer solution of the equation M & # 178; - N & # 178; = 60~

4 / 3x + 3 / 2Y = 7, both sides multiply by 6 to get 8 / x + 9 / y = 42 1) 5 / X-6 / y = 3 2) 1) × 2 + 2) × 3) to get 16 / x + 18 / y + 15 / x-18 / y = 84 + 931 / x = 93x = 1 / 3, substituting x = 1 / 3 into 2) to get 15-6 / y = 3Y = 1 / 22, M & # 178; - N & # 178; = 60 (M + n) (m-n) = 60, because m and N are positive integers, then there exists the following formula

When the altitude increases by 1000 meters, the temperature will decrease by 5 degrees Celsius. Now the ground temperature is 8 degrees Celsius. What is the altitude temperature of 3000 meters?