Find the minimum distance from point P to point m (m, 0) on ellipse x ^ 2 / 3 + y ^ 2 = 1

Find the minimum distance from point P to point m (m, 0) on ellipse x ^ 2 / 3 + y ^ 2 = 1

d^2=(x-m)^2+y^2
y^2=1-x^2/3
d^2=(x-m)^2+1-x^2/3
Simplification
2/3[(x-3m/2)^2-3m^2/4+3/2]
When x = 3m / 2, it is the smallest
d^2=1-m^2/2

Seek synchronous analysis and evaluation of Mathematics Grade 5 Volume 8 last question answer!
Calculate the following questions in a simple way
2.5*3.8*0.4*0.2
2.7*10.2
6.5*1.9-6.5*0.9
9.8*25

(2.5*0.4)*(3.8*0.2)
2.7*10+2.7*0.2
6.5*(1.9-0.9)
9.8*100/4

How to find the position relationship between the space line L1: 4x + y + 3Z = 0,2x + 3Y + 2Z = 9 and L2: 3x-2y + Z = - 5, x-3y-2z = 3?

The direction vector of L1 is
s1=（4,1,3）×（2,3,2）=（-7,-2,10）
The direction vector of L2 is
s2=（3,-2,1）×（1,-3,-2）=（7,7,-7）
It is neither parallel nor vertical, and the prediction should be different

Do you have any information about unit 1 of grade 5?

1. Write the number (1) 640 △ 80 = 270 △ 30 = 61 × 7 = (2) 540 + 20 = 720 △ 18 = 9 + 9 △ 9 + 9 = 2. Calculate the following questions in vertical form, and check the calculation. (3) 4278 △ 62 = (4) 5729 △ 44 = 3. Simple calculation (write the simple calculation process) (5) 1892-187-513 (6) 7963-2998 4

If the side length of a square is increased by 3 cm, the area will be increased by 39 square meters. What is the side length of the original square?

Let the length of the original square be x cm
(3+x)²-x²=39
9+6x=39
6x=39-9
6x=30
x=5
A: the original side length of a square is 5cm

How to judge the relationship between velocity direction, acceleration direction and displacement in simple harmonic motion?
Hope to be able to explain the relationship between them in detail, I have read the previous post, hope not to copy. Do not understand do not disturb

First, the direction of velocity is the direction of motion. This is very simple
Second, the direction of acceleration is determined by the direction of the restoring force, which always points to the equilibrium position, regardless of the direction of displacement
Third, the displacement is also a vector, there are positive and negative points, is relative, this need to specify a positive direction

A rectangular iron sheet is 80 cm long and 40 cm wide. Now we need to make this iron sheet into a 10 cm deep uncovered rectangular iron box (the thickness of welding joint and iron sheet is ignored). How many cubic centimeters is the maximum volume of this rectangular iron box?

Long as:
80-10 × 2 = 60 (CM)
The width is:
40-10 × 2 = 20 (CM)
Maximum volume:
60 × 20 × 10 = 12000 (cm3)

Is the average speed the same as the average speed? What's the difference?

It's not the same
1、 Definition: the average speed is the distance in unit time (the route passed); the average speed is the displacement in unit time (the vector of the first and last positions of the particle in this period)
2、 Velocity has only one size, which is scalar; besides size, velocity has direction, which is the tangent direction of the trajectory curve, which is vector;
3、 Formula: average speed = distance / time; average speed = displacement / time;
Maybe the above is more abstract. Let me give you an example
When you go to school in the morning, you make a detour to a snack bar for breakfast. That is to say, you first go from a to B and then to C. then your average speed is the total route you have traveled divided by the time you spent. But the average speed is the vector (equivalent to connecting line) / time spent from your home to school. That is to say, the average speed has nothing to do with the way we arrive
It should be noted that the velocity is the magnitude of the velocity, but the average velocity is not necessarily equal to the magnitude of the average velocity
By the way, let's talk about your next question. It doesn't matter what symbol you use. It's just like your name is just a code. No matter what name you are, it's just like you. If you know it's the average speed, it's pull. The formula is on it,
It's a long time since you graduated from high school. Some of them may have been omitted for reference only. It's suggested that you read the reference books of senior one you used, which should be in the second or third chapter of senior one

As shown in the figure, the generatrix length of the cone is 6cm, and its side expansion is semicircle. Find: (1) the bottom radius of the cone; (2) the degree of ∠ BAC; (3) the side area of the cone (the result retains π)

(1) Let the radius of the circle be r, then 2 π r = 6 π cm. The solution is r = 3, and the radius of the bottom of the cone is 3; (2) ∵ LR = 2, if the angle between the height of the cone and the generatrix is 30 °, then BAC = 60 °; (3) ∵ r = 3cm ∵ L = 2R = 6cm, then the side area of the cone is π L22 = 18 π (cm2)

Put the serial number of the correct answer in brackets (Mathematics)
1. Put four cube wood blocks with equal edge length into a cuboid at will (use four blocks each time), and you can put them into () kinds
A：1 B：2 C：3 D：4
2. The area of four sides of a cuboid is equal, and the other two sides are ()
A: Cuboid B: cube C: not sure
A cube of 3.1 cubic meters can be divided into () small cubes of 1 cubic meter
A：10 B：100 C：1000
4. A cuboid is 3cm in length, 1cm in width and 2cm in height. The sum of its edges is () cm
A：12 B：24 C：32
5. Use the same small cube block to make a big cube, at least use this small block
A：2 B：4 C：8 D：16
6. Put a cube with a surface area of 6 square decimeters on the ground, and the exposed surface is () square decimeters
A：2 B：3 C：5 D：6
7. The surface area of a cube whose edge length is 6cm is ()
A：36cm2 B:36cm3 C:216cm2 D:216cm3
8. The cuboid without cover is 2 / 1m in length, 1 / 3 in width and 1 / 4 in height. Its surface area is () m2
A: 3 / 4 B: 7 / 12 C: 1 / 24
9. Put two small cubes with the edge length of 2cm into a cuboid, and the surface area of the cuboid is () cm2
A:48 B:44 C:40
Amendment to question 3:
The cube of 1 cubic meter can be divided into () small cubes of 1 cubic decimeter.
A：10 B：100 C：1000

A: 1, B: 2, C: 3, D: 4 2. The area of four sides of a cuboid is equal, and the other two sides are (b). A: cuboid B: cuboid C: a cuboid that can't determine 3.1 cubic meters can