Imaging principle of projector If the image is to be bigger on the screen, should the projector increase or decrease the distance from the screen

Of course, the distance is increased. The plane mirror only changes the direction of light. Except for this plane mirror, the rest is the same as when you take the projector and direct it on the screen

What is the imaging principle of projector
Yeah. '
It's about the imaging principle of the projector. I want to be clear and specific,

In a word, the imaging principle of liquid crystal projector is to magnify the image on the liquid crystal panel into a real image on the screen through the projection optical system, that is, the lens, so that many people can watch it. The projection objective is equivalent to a positive lens, and the liquid crystal panel is located between 1-2 times of the object square focal length of the projection objective, then the amplified real image will be obtained

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When the teacher puts the projection in class, the pattern on the projector forms an enlarged image on the screen. The distance from the projector to the lens should be within the scope of lens (), and the distance from the screen to the lens should be ()

During projection, the pattern on the projector forms an enlarged image on the screen. The distance from the projector to the lens should be within the range of the lens (greater than the focal length and less than twice the focal length), and the distance from the screen to the lens (beyond the double focal length)

If M = {x ∈ n | 8-x ∈ n}, then the number of elements in M is (a.10 B.9 c.8 d.7)
If M = {x ∈ n | 8-x ∈ n}, then the number of elements in M is（
A.10
B.9
C.8
D.7
thank you very much.

x> And 8-x > = 0, so 0=

It is known that: as shown in the figure, point C is a point on the line AB, and 3aC = 2Ab. D is the midpoint of AB, e is the midpoint of CB, de = 6, find: (1) the length of AB; (2) find ad: CB

(1) Let AB = x, ∵ 3aC = 2Ab, ∵ AC = 23ab = 23x, BC = AB-AC = x-23x = 13X, ∵ e be the midpoint of CB, ∵ be = 12bc = 16x, ∵ d be the midpoint of AB, ∵ DB = 12ab = X2, so de = db-be = x2-x6 = 6, the solution is: x = 18, so the length of AB is 18; (2) from (1), ad = 12ab = 9, CB = 13ab = 6, so ad: CB = 32

An advanced problem: A is a matrix of order n, R (a) = R

It is proved that there exists an invertible matrix P such that PAP ^ (- 1) = B, where B is a partitioned matrix and the R * r submatrix B in its upper left corner_ We construct M0 = B + C, where C is a partitioned matrix and its lower right corner is the identity matrix e of (N-R) * (N-R)_ We construct MI, I = 1,..., N-R as follows

p: 6 is the divisor of 12 or 24, Q: 6 is the divisor of 24,
"P ∨ Q" is
"P Λ Q" is

P ∨ q is a union, that is, the broader one: 6 is a divisor of 12 or 24
P ∧ q is the intersection, that is, the small set, the common set: 6 is the divisor of 24

Let f (x) be a continuous function and prove: ∫ (0, π) f (cosx) DX = 2 ∫ (0, π / 2) f (SiNx) DX

Let t = x - π / 2
Left = ∫ (- π / 2, π / 2) f (COS (T + π / 2) DT)
=∫ (- π / 2, π / 2) f (Sint) DT
Because f (Sint) is an even function
So = 2 ∫ (0, π / 2) f (Sint) DT
And because of 0

Duck duck plural plus s?

Plus s

In order to encourage the public to save water, a city has formulated the following charging standards. If the water consumption of each household is less than 10 tons per month, it will be charged at the water price of 1.1 yuan / ton, and the sewage treatment fee of 0.1 yuan / ton will be added. If the water consumption is more than 10 tons, it will be charged at the water price of 2 yuan / ton, and the sewage treatment fee will remain unchanged. For example, the average water fee paid by a Hu resident in a certain month is 1.6 yuan / ton, So how many tons of water does he share this month

Let's use x tons of water 10 * 1.1 + (X-10) 2 + 0.1X = 1.6x 11 + 2x + 0.1x-20 = 1.6x 0.5x = 20-11 0.5x = 9 x = 18. It's the first time that I've got such a complete title... Please give it to me

Imaging principle of projector If the image is to be bigger on the screen, should the projector increase or decrease the distance from the screen