I'm having a bit of a problem with knowing where to start at all.

The task states (Somewhat directly translated going forward):

"You have laid a water pipe up to a mountain lake on the uphill side of your cabin. As evident from the terrain, the water pipe passes over an elevation higher than the water level. In order to get water out of tap K, the water pipe must be free of air and completely filled with water. The system operates according to the principle of a siphon"

"Task b): Determine the waterpressure aganst the water tap (K) when it's closed, and the waterpipe is completely filled with water".

In task a) I had to find data or information through external sources on mass density of water and normal pressure of air, which resulted in:

'rho'Air (Standard atmospheric pressure) = 1,01x10^(5) Pa
'rho'Water (*Mass density of fresh water at 25^(o)C) = 0,99 kg/m^(3)

I understand that I might have to use the equation for hydrostatic pressure (p = p0 + 'rho'gh), but I can't for the life of me force my remaining braincells to process a logical way to proceed with it, considering there are multiple heights to respect throughout the calculations, also when there is a closed end on the pipes.

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Hi, I've attempted severally to solve the attached trigonometric question but have been unable to reduce the equation to a singular function.

Any help would be much appreciated.

We're doing a debate/persuading project in English about who we think was the murderer/ or what happened in the RedPath Mansion Murder. I'm stuck between two options: Murder-suicide, since it's reasonable Clifford killed himself as well as his mother. I also heard a theory on how he was gay (couldn't find an actual site stating it, so not sure how people got to that point). And murder, since Peter could've killed them both. I need it to be convincing, as well as "why would (person/people) do that?" "what do they get out of it" "how does that make sense" that sorta thing, since they'll be questioning us, so I need to have rebuttals ready. I need to convince four old teachers I'm right.

Determine whether the function is a linear transformation.

T: R2 → R2,

T(x, y) = (x − h, y − k), h ≠ 0 or k ≠ 0 (translation in R2)

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what i started doing

Property 1 of vector addition:

let x = (x1,x2) and y = (y1,y2) be vectors in R2

then (x+y) = (x1,x2) + (y1,y2) = (x1+y1, x2+y2)

T(x+y) = T(x1+y1, x2+y2)

from here idk how to proceed and show that this function is not a linear transformation.

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can someone explain this in a non textbook type explanation cause i already read enough of it and it doesnt help much with explaining linear transformations in general.

Can someone please check to see if my understanding is correct. Attached is the question. The problem asks if this set is a basis for R3. The answer I gave was: "Yes, because this is an orthogonal set of nonzero vectors, it is linearly independent, and thus a basis for the subspace R3." Essentially, I just assumed any orthogonal set that's missing the zero vector would be a basis for the subspace. Is that right? Any help provided would be appreciated. Thank you in advance for your time and help

First off, I'm not from the US or UK, so I don't know if the flair is accurate for the problem really... It's essentially first (maybe second in some places) semester mathematics at uni.

Just started on double integrals etc. and I'm having a hard time getting my head around it. I'm mostly looking for more explainations of the general process of how you should think about the limits of the integrals when you change the order of them. As an example... (and I'm sorry, but reddit is just not very good for math formatting)

Say we have an outer integral with the limit 1 -> 7 and with respect to x, and an inner integral with the limits 0 -> 1/x and with respect to y. The integrand is just some multiple variable function f(x, y). Int 1 -> 7 (Int 0 -> 1/x f(x, y) dy)dx, if that makes it more clear. Now we want to change the order of the integrals. Since we don't have an actual function I'm finding it hard to picture what I'm "looking" at, geometrically speaking, from just the limits, so I'm unsure of how to handle them.

Anyone have any good tips for this problem? Thanks!

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actually, the method of finding the i(t) is pretty straightforward forward just find i(0) for t<0 (or when the switch is closed) and find i(t) for t>0. what is confusing to me is when I short-circuit the inductor I don't know which resistors remain in the circuit and how I find the i(0). I would appreciate it if anyone could give me any pointers to understand this more clearly.

Thanks in advance

So my physics teacher gave us a project where we need to give a 20-25 min lesson about a topic we didn’t get to this year. I chose simple harmonic motion and I here is my lesson plan: Start with definition of Simple harmonic motion Demonstration of a weight attached to the end of a slinky Draw a series of free body diagrams on the board to explain acceleration,force, and velocity in simple harmonic motion. Explain how the energy oscillates between kinetic and potential energy. Explain Hooke’s law Show a simulation of graphing the position and time of a spring mass system. Explain how to graph simple harmonic motion and give the equation. Give a real world example of simple harmonic motion. Explain how it affected the millennium bridge.

I feel prepared for the presentation but I need to write 5 questions that will likely be asked and I need to write the answer to those questions. But this does not make sense to me. If I know people will ask these questions then why don’t I put the answers to them in my presentation? But anyway I need help thinking of 5 likely questions, if anyone has ideas please comment them. Thank you!

I'm doing a thin lens equation practice sheet where I got the question "A diverging lens has a focal length of 20 cm and has an image at 35 cm. Calculate the distance of the object from the lens." I did:
1/dₒ - 1/35 = 1/-20
1/dₒ = 1/-20 + 1/35
1/dₒ = -0.05 + 0.2857...
1/dₒ = -0.02142...
1 = -0.02142... * dₒ
dₒ = -46.6667
However to my knowledge a negative dₒ should not be possible, my teacher also said that a negative dₒ should not be possible. I can't see any mistakes but I'm not the greatest with math could anyone help thank you.

The following data were taken from Pharaoh company Net sales 2025 $6420000. 2024 $6146000. Beginning inventory 2025 $967700 2024 $771500. Purchases 2025 $4807805 2024 was $4631160. Ending inventory 2025 $1173000 2024 $976700. Please help me find the inventory turnover for each year and also days in inventory for each year. Thank you in advance!

My college professor said the title: "(-∞, +∞) does not include 0, but (-∞, ∞) does"

He explained this:

∞ is different from both +∞ and -∞, because ∞ includes all numbers including 0, but the positive and negative infinity counterparts only include positive and negative numbers, respectively. (Can infinity actually be considered as a set? Isn't ∞ the same as +∞, and is only used to represent the highest possible value?)

He also explains that you can just say "Domain: ∞" and "Domain: (-∞, 0) U (0, +∞)" instead of "Domain: (-∞, ∞)"

Is my professor correct and I am just stupid? Or is it the other way around? Hopefully I'm wrong as I would need to change classes otherwise.

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So this problem is related to wye and delta transformation but im confused on where should i start. Thanks in advance

Hi all, for an assignment I was asked to show graphical or statistical evidence to support why the test I chose (independent sample t-test) is the best fit for the research question. How do I go about doing that? I’m completely lost and would appreciate some help, thanks!

Hi all, I'm not sure if this is the correct subreddit/if this is allowed here, but I need help with my introduction of my bachelor thesis in psychology :( I don't need any factual help, it's just purely writing. I have already incorporated the feedback of my supervisor as well as I could, however I would really like an outsider to read it and tell me if it makes sense. I can send the introduction to whomever is interested in reading it. I don't need super detailed feedback :)

Hi all, I'm struggling to comprehend how to find the parallax angle from a graaph of RA vs Dec values in mas, I'm not sure how to find the parallax without using the formula d/pc = (parallax/arcsec)^-1 in one of my exercise books I'm being asked the following:

This question concerns analysis of astrometric and photometric data such as that returned by the Gaia spacecraft

Figure 1 presents a set of (simulated) data spanning 5 years, shown by the red points, illustrating the apparent motion of a star on the plane of the sky. The blue line is a fit to the combined proper motion and annual parallax. Figure 2 represents the same data, but with the star’s proper motion subtracted. In this case, the blue line is a fit to the parallax alone. The x-axis is parallel to the plane of the Earth’s orbit in each case.

• i.By taking measurements from Figure 1, determine the proper motion of the star, in each of the x and y directions, in milliarcseconds per year.
• ii.By taking measurements from Figure 2, determine the annual parallax of the star, in milliarcseconds.

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Figure 1

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Figure 2

I'm not looking for the answer, just an understanding on how to solve for the parallax from the information I have.

Hello! I'm doing a project analyzing the foodscape of a small city within San Diego. The problem? I need 3-4 peer reviewed articles on the subject.

I am struggling so hard to find any peer reviewed articles relevant to my project. I am using my college's library search function, but none of the articles that come up are relevant to my project.

I'm going nuts.

Is anyone able to help? Do you know of any resources that'd help me find peer reviewed articles, outside of my school's library?

Google scholar isn't inherently peer reviewed, so I have to look through every darn article so that I can determine if it's peer reviewed or not.

Please help. Thank you.

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No idea where to even start for this. I know the sum of a series is (a/(1-r)), but it doesn't seem to work for this.

Hi everyone, I cannot seem to get the answer without being given a surface temperature. Does anyone know how to solve this?

If the incoming longwave radiation is 200 W/m^2, and incoming shortwave radiation is 150 W/m^2, calculate the net radiation. Assume albedo is 0.9 and the surface emissivity is 0.1.

I want to know how I can convert radicals and exponents that include decimals in their conversion. It's because I have not seen a question like this. I want to know how to solve this.

and also never seen a exponent with decimals in it

The question is (6v) to the power of 1.5

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