The solution of the inequality ax ^ 2 - (a ^ 2-4) x-4a about X

The solution of the inequality ax ^ 2 - (a ^ 2-4) x-4a about X

(ax+4)(x-a)0,a

How to solve x inequality (1 + ax) / 3 + (4a-x) / 2 < A / 6

The first step is to divide
2 + 12a + (2a-3) X1.5
Get x

A uniform thin rod, m in mass and l in length, falls freely from a static position around the horizontal axis at one end
Calculate the angular velocity when the angular acceleration bar turns angle a at the initial time, and the kinetic energy when the angular acceleration bar turns angle A

1,
Mo=IBo
（1/2）mgL=(1/3)mL^2Bo
Bo=3g/2L
2,M=IB
mg(L/2)cosa=(1/3)mL^2B
B=3gcosa/2L
dw/dt=wdw/da=B
wdw=(3g/2L)cosada
Integral gain
W = root 3gsina / L
three
E=(1/2)Iw^2=

How many kilos is one ton?

1000

How much buoyancy does a 100 cubic centimeter iron block weigh 7.64n when it is completely submerged in water? If the iron block is hung on the spring scale, will the spring scale read?

Buoyancy = ρ GV = 1000 * 9.8 * 10 ^ (- 4) = 0.98n
Reading = Mg-F (floating) = 7.64-0.98 = 6.66n

Given that the perimeter of a rectangle is 12, let one of its sides be x (0 ＜ x ＜ 6), then the functional relationship between its area y and X is______ .

On the other side: 12 / 2-x = 6-x
y=x(6-x)=-x^2+6x.(0

As shown in the figure, the masses of objects a and B are ma and MB respectively, and Ma ＞ MB. The whole system is at rest, and the mass of pulley and all friction are ignored. If one end of the rope moves slowly from point Q to point P, how does the height of object a and the angle θ between the rope and the horizontal direction change after the whole system rebalances ()
A. The height of object a increases; B. the height of object a decreases; C. the angle of θ remains unchanged; D. the angle of θ decreases

When the fixed point Q at one end of the rope is moved slowly to the right to P, the tension of the rope will not change. Analyze the stress of the movable pulley, and make a diagram as shown in the figure. Suppose the tension of the rope is f, and the angle between the two ropes is 2 α. Since the tension of the ropes on both sides of the movable pulley is symmetrical with respect to the vertical direction, then there is & nbsp; & nbsp; & nbsp

What is the order of mixed integer operations

From left to right,
Multiply and divide first, then add and subtract,
If there are brackets, count them first,

The arc track AB is a quarter circle with a radius of 2m in the vertical plane
At point B, the tangent line of the orbit is horizontal. A small ball with a mass of 0.2kg is released from point a without initial velocity, and the velocity when it moves to point B is 5m / s. what is the work done by the object to overcome the resistance in the process of sliding
There is an arc between a and B
`
`
`
Point B

Law of conservation of energy
The work done by the body to overcome the resistance = the change of gravitational potential energy - the change of kinetic energy
(sorry, the letters are hard to type)
W=4-2.5=1.5J

It is known that the sequence {an} is an arithmetic sequence, the sum of the first n terms is Sn, A3 = 7, S4 = 24. (1) find the general term formula of the sequence {an}; (2) let P and Q be positive integers, and P ≠ Q, prove that SP + Q < 12 (S2p + s2q)

(1) Let the first term and tolerance be A1, D respectively. From A3 = 7s4 = 24, a1 + 2D = 74a1 + 6D = 24, so A1 = 3D = 2, then an = 2n + 1; (2) 2SP + Q - (S2p + s2q) = 2 (P + Q) 2 + 4 (P + Q) - 4p2-4p-4q2-4q = - 2 (P-Q) 2 ≤ 0, so SP + Q ≤ 12 (S2p + s2q)