If A2 = 1-A, B2 = 1-B and a ≠ B, then (A-1) (B-1)=______ ．

If A2 = 1-A, B2 = 1-B and a ≠ B, then (A-1) (B-1)=______ ．

Therefore, the answer is: a2b2

The resistance of air is proportional to the square of velocity

According to the air resistance formula: F = (1 / 2) C ρ SV ^ 2, where: C is the air resistance coefficient; ρ is the air density; s is the windward area of the object; V is the relative velocity of the object and the air. It can be seen from the above formula that under normal conditions, the air resistance is directly proportional to the air resistance coefficient and the windward area, and is directly proportional to the square of the velocity

If the power of the engine is p when the aircraft is flying at constant speed V, then the power of the engine is ()
A. nPB. 2nPC. n2PD. n3P

When the aircraft is flying at constant speed V, the power of the engine is p, then p = FV, and the traction force is f = Kv2, then p = Kv3. When the aircraft is flying at constant speed V, the power of the engine is p ′ = f ′ NV = f ′ NV = K (NV) 2nv = n3kv3 = n3p

Zhang Ming and Wang Hua are 25 years old. When Wang Hua was as old as Zhang Ming, their age ratio was 3:4
Please make a formula
But the answer is that Wang Hua is 15 years old.

The age ratio of the two is 3:4. Is that Wang bizhang~
Let Zhang Ming be X this year. Let Wang Hua be 25-x this year
When Wang Hua is as old as Zhang Ming, that is, when Wang Hua is x years old, Zhang Ming is 3x-25
So when Wang Hua is x, Zhang Ming is 3x-25
So we get 3x-25 / x = 4 / 3, and we get x = 15 from the equation. So Wang Hua is 10 years old this year

For calculus Y "_ The general solution of Y '- 6y = 0

Characteristic equation: R & # 178; - R-6 = (R-3) (R + 2) = 0
r=-2,3
y"_ The general solution of Y '- 6y = 0
y=C1e^(-2x)+C2e^(3x )
C1 and C2 are arbitrary constants

A middle school organizes an autumn outing for Junior One students to rent buses from a bus company. If some 45 seat buses are rented, 15 people will have no seats; if the same number of 60 seat buses are rented, 30 seats will be vacant
(1) Please count the number of students in grade one of the middle school
(2) If the rental of a 45 seat bus is 250 yuan / vehicle and that of a 60 seat bus is 300 yuan / vehicle, how can the rental cost be the least? What is the minimum cost?

If x cars are rented, 45x + 15 = 60x-60
Then x = 5
Number of people = 45x + 15 = 240
45 = 250x6 = 1500
60 money = 300x4 = 1200
At least 1200 yuan

It is known that K is an integer and the solution X of the equation KX = 4-x is a natural number=______ ．

KX = 4-x, ∵ KX + x = 4, ∵ (K + 1) x = 4, x = 4K + 1, ∵ the solution of the equation KX = 4-x is an integer, K is an integer, the value of ∵ K + 1 can only be 1, 2, 4, and the value of ∵ K is 0, 1, 3

The weight ratio of the original stones of Party A and Party B is 3:4. When Party B transports 108 tons to Party A, the weight ratio of Party A and Party B becomes 4:3,
How many tons of stones did each team have?

Each team has 3x and 4x tons of stones
(3x+108):(4x-108)=4:3
(3x+108)*3= (4x-108)*4
9x+324=16x-432
7x=324+432
77 x=756
x=108
Therefore, each team has 324 and 432 tons of stones

By translating the line y = 2x + 1 downward by 3 units, the obtained line is solved as?

x=0,y=2x+1=1
That is y = 2x + 1 over (0,1)
Translation down 3 units
1-3=-2
So (0, - 2)
The coefficients of X are equal in translation
So y = 2x + B
Over (0, - 2)
-2=0+b
So it's y = 2x-2

The number of boys in class 601 is one sixth more than that of girls, 30 girls. How many students are there in the class

Number of male students = (1 + 1 / 6) * 30 = 35
Class size = 35 + 30 = 65