#help-0

1 messages · Page 733 of 1

warped phoenix
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yeah

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this is a really garbage course

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i believe you were the one who told me for an earlier question that was also wrong to appeal that the question's answers were all incorrect

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if i were to do that that would be a lot of appealing

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because to say there are things here being taught incorrectly is an understatement lmfao

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the course was recommended to me by my school, i shouldve went with john-hopkins instead 😦

noble sinew
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Uni course?

warped phoenix
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im taking it to test out of algebra II so i can go into pre-calc next year

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tho idk if i can pass the test to test out of it if a bunch of stuff im being taught is wrong 😅

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we'll see

noble sinew
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Ye well... What you have above is a multionomial model. But I'm curious how your teacher got to that conclusion ever. We can easily see that 80 * 0.223 is not an integer for example so it is impossible for our simulation to be "consistent" if consistent in his mind means exact same probability.

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and if he is like oh it just needs to be close to the true probability then there clearly is a difference whether the simulation was for 80 or for 80000 for example (like with the coin thing mentioned above for example)

glacial hedge
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I have taken certain math courses through CTY and was tryign to take a math course at UW, however they said that the CTY courses weren't "college level" courses and that I couldnt test through the courses.... So i would have to take calculus if I were to take a course at UW. Does anyone know what to do... oviously tkaing calculus, multi, and the following courses would be a huge waste of a year and tons of money. Does anyone have any suggestions... I cannot go to a different college to take courses because UW is the only college without an age requirement (I am going into highschool this year)

noble sinew
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I mean they even say on there website it doesn’t count as college courses

solar cradle
#

University of Wisconsin or Washington?

noble sinew
#

So not really sure what you expect

solar cradle
#

Many schools do have placements tests that can place you into calc 3 right away. You could also seek instructor consent to take other courses

glacial hedge
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washington

solar cradle
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Which course were you considering taking?

glacial hedge
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they dont have a placement test

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I was tryign to take linear analysis

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They said I would have to go into calculus 1.....

solar cradle
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linear analysis or algebra?

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or is that the same at UW?

glacial hedge
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analysis (p.d.e + fourier and stuff)

solar cradle
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yeah, it's probs pretty unlikely you'd be able to skip into an upper level course like that :/

glacial hedge
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wdym

solar cradle
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I was in the same boat, it kinda blows but often taking calc at a good university can be enlightening

glacial hedge
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but it would be a tremendous waste of time and money?

solar cradle
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Is there a youth options program in your hs?

glacial hedge
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nope

solar cradle
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You could consider reaching out to the prof and ask to audit the class if you just want to learn the material, but if you're looking for credit they'll probably want to vet you to make sure you're able to perform in university level courses

glacial hedge
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yeah probably want credit unless I want to do this again when i go to college....

solar cradle
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Depending on how rigorous CTY was, in good math schools the calc sequence is taking pretty seriously and can be a good intro into analysis

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That's what i mean by enlightening

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Is Calc 1 the only class you have available?

glacial hedge
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yessir

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i cant test out of it

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becauser i didnt take the ap

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exam

solar cradle
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After taking calc 1 would other courses open up or would you be stuck in the calc sequence?

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What are the prereqs for analysis level courses at UW?

glacial hedge
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its a pretty low level course... only 200 level

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differential and linear algebra are prefequs

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I think I would still be stuck... and what sucks even worse is I can only take 1 class per semester because of hs...

solar cradle
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I think you may just be stuck in the system here, even if you wait until college it's likely you wouldn't be able to test past calc 3 without college credit

glacial hedge
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:/

solar cradle
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Have you looked into online courses at other universities?

glacial hedge
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yes

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all of the other universities

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dont.. offer courses past calculus

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and if i want to take university courses.... all of the other ones have age reqs

heavy spear
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I need help with this quest8ion

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please

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aw man i posted here would you mind posting in another section?

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otherwise i will its fine

kindred dock
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I'll post somewhere else

heavy spear
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its fine ipostred in question 1

little lotus
heavy spear
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no i just need to know how to do iut

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<@&286206848099549185> can u help with the above picture

coral pagoda
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Well, we know the function is continuous everywhere except x=-1.
To make sure the function is continuous at -1, both left and right hand limits need to be the same and the limit is f(-1)

ocean sealBOT
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dackid (jump king +)

coral pagoda
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Now, try to determine how to use this knowledge to figure out a solution

coral pagoda
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Keep in mind I did not give you an answer, I only gave you a helpful way to think about the problem in order to figure out the answer yourself.

heavy spear
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ye i always forget the parts i need to solve i know how to

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but i forgot the small parts

coral pagoda
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Sounds like you know where to go from here 🥳

alpine sable
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Hey everyone. Can anyone help me with this? I dont understand where is underline, where the number 1 is.

solar cradle
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Are you asking how they go from the second line to the third line?

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If so, its just the definition of $Im(z)$ and $Re(z)$. That is, for $a,b \in \mathbb{R}$, then $Im(a + ib) = b$ and $Re(a+ib) = a$.

ocean sealBOT
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Billy Clintorus

alpine sable
misty thistle
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Fairly easy question Im just kind of stumped.
The start up costs of a farm is $1,840,000. Each harvest costs $560,000 in resources and labour but the produce is sold for $780,000 for $220,000 profit per harvest.

How many harvests will take until they are in the green. (paid for the starting costs and bearing in mind each harvest costs $560,000)

ionic jewel
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they make $220,000 per harvest, and need to pay off $1,840,000

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how many harvests will it take?

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maybe that rewording will help?

misty thistle
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omg it really is that simple

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thank you

red lagoon
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@astral dagger yes its convolution \

modern wren
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would this be a correct solution?

elfin talon
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@modern wren I don’t have the brain power to look at the problem rn, I still have some feedback, the modulus operator is “%” so “1 mod 7” is 1 % 7

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Just make sure to add a space between and the other values so it’s not mistakened with a percentage

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Although I think the concept is context oriented

slate arrow
placid zinc
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@slate arrow
First make useful variables. What would the variables be?

slate arrow
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x

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the dad woul;d be 3x

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the son would be x

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the daughter would be x-3?

placid zinc
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Yeah very nice! That does work

slate arrow
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yeah

placid zinc
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What would their ages be 3 years ago?

slate arrow
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hmm

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oh i didnt see that part lmao

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ok so

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(3x-3)+(x-3)+(x-6) = 63

astral dagger
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beautiful

placid zinc
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And with that, you're basically done. Solve for x

slate arrow
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x = 15??

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@placid zinc

slender forge
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Look at what u let x equal

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If the son is 15 what would the father be

slate arrow
#

46

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45*

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oooh

astral dagger
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well done boy

slate arrow
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then the daughter would be 12

placid zinc
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👏

slate arrow
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no but that doesnt sound right

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if its 12 15 and 45

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thats 72

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not 63

astral dagger
slate arrow
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oh yeah that is right

slender forge
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U calculated current age correctly u good bro

slate arrow
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9 years

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ok so thats right

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x = 15

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ayyyy

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thanks guys

slender forge
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Yes and they ask for father

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Make sure u put 45

slate arrow
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father is 45

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yep

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k thx

sick phoenix
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can someone explain iv pls

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ty

ocean sealBOT
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SubGui

idle axle
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,help

ocean sealBOT
#

A brief description and guide on how to use me was sent to your DMs!
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idle axle
#

,list

ocean sealBOT
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analog gulch
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if I have a tree with 10 layers. each node has 100 children, starting from one top node.

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how many will there be in the bottom layer

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(I'm to tired to do this right now)

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wait

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it's 100^10 right?

sick phoenix
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I don’t get how you find k

ionic jewel
oak chasm
# sick phoenix I don’t get how you find k

You need to figure out where you first get a repeated output. When you get two inputs with the same output, the inverse has one input with two different outputs, which isn't a function.

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Does that make sense?

slate arrow
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How do I write an expression for 6 less than half of x

vernal flower
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Try to break your problem down. Figure out how to write "half of x", then 6 less than the stuff I indicated in quotes

slate arrow
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uh

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0.5 over x in a fraction???

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so 6 - 0.5/x

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no

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thats not right

vernal flower
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So let's approach this problem with a simple example

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Let's just say that x is $10 in this case

slate arrow
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how do I write half of x

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yeah

vernal flower
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What is half of x? In this case

slate arrow
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well 10 / 2

vernal flower
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Yep, and because of the type of question this is, you can simply substitute 10 for x

slate arrow
#

so x / 2

vernal flower
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Yep. That's "Half of X"

slate arrow
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so 6 - x/2

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?

vernal flower
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Let's not try to guess. Try to use things you know to approach things you don't know

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Let's use x being 20 now that we're tackling the 2nd part of the question

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You know that 20 / 2 is 10

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Let's say 20 / 2 is "that", or "y", or whatever you want to call it

slate arrow
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uh

vernal flower
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Your question again was "expression for 6 less than half of x"

slate arrow
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yep

vernal flower
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So then let's substitute "20 / 2" for "half of x"

slate arrow
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right

vernal flower
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So your question for example would be "expression for 6 less than 20 / 2"

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What would 6 less than 20 / 2 be?

slate arrow
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so it would be 4

vernal flower
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In this case, yep

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So then would you get 4 from "6 - 20/2" (your earlier guess)?

slate arrow
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oh

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x/2 - 6 lol

vernal flower
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Correct. You've learnt to

  1. Use a small enough value like 10 or 20 that you can comprehend to wrap your head around a problem
  2. Use a small enough problem that you've already solved to solve a bigger one
slate arrow
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gotcha

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thanks!

vernal flower
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You're very welcome 🙂 Try to use the similar approaches when solving questions in the future. Keep in mind of the techniques you learn because they will be extremely valuable in many aspects of life

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Could someone with more teaching experience mention how I could've helped better? I felt like I didn't know how to bridge the gap between the "6 less than 20 / 2" (my own brain has problems wrapping around the question lol) but I felt like my approach was nice, short, and sufficient for what was requested

tulip sedge
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y=|cosx| is not differentiable at x= (2n+1)pie/2 . can someone explain why is it not differentiable at this point?

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this is part of my practice test

placid zinc
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Note that |x| is not differentiable at x = 0, so you care about when cos(x) = 0

steel palm
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can somone pls check channel 1 once they are done pls

empty bane
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adakah orang indonesia disini ?

lapis valley
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hey

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need help

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so my constraint is 4x+3y = 2

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and my equation is x^2+sqrt(3)/8y^2

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but when i differentiate i get a different answer to the solution

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they used a different method but i should get the same area

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,rotate

ocean sealBOT
lapis valley
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,rotate

ocean sealBOT
lapis valley
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where did i mess up

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sry this stuff is too hectic but i appriciate if anyone can help me

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the minimum area should be 0.11, and i got 0.07

tough hatch
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@lapis valley

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you probably thought of asqrt(3/4) as sqrt(3)/4

cloud rain
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X x 2 is 2x or x^2?

lapis valley
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i wrote it like this sqrt(3)/4

ocean sealBOT
lapis valley
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yea

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i wrote it like sqrt(3)/4

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where did i make this mistake

ocean sealBOT
tough hatch
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work from there

lapis valley
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ok

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thanks

hollow pelican
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hi is 1a and 1b like this?

rigid island
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this is a little weird, don’t you usually i for imaginary numbers?

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or am is this not it

hollow pelican
#

for engineering is j

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i think

rigid island
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oh hahaha sorry

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i’m just a high school student trying to learn

hollow pelican
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ohh

rigid island
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but from what ik it looks right all tho 1b it. doesn’t look like it’s (-7,2)

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it should be quadrant 2

hollow pelican
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!rotate

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,rotate

ocean sealBOT
rigid island
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nah um so just think of graphing real numbers

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the point (-7,2)

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like that

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i could be wrong but that’s what it would be

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logically

hollow pelican
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Ohh

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ok

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i think its correct

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thanks

rigid island
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np

solar widget
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yo i dont get this

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can someone check on it a lil

alpine sable
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How is this statement correct?

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17^2=289

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8^2=64

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289+64=353

tough hatch
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no

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c=17

median tendon
tough hatch
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a=8

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b=15

alpine sable
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I had to calculate the right side

tough hatch
#

c is the length of the hypotenuse

alpine sable
#

the opposite side

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I had the adjacent and the hypoteneuse

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and I had to get the opposite

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so I had a=17 and b=8

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That's all I had

tough hatch
#

you are using the theorem incorrectly

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you are not listening

alpine sable
tough hatch
#

c is the length of the hypotenuse

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what length does the hypotenuse have in your triangle?

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hypotenuse is the longest side

alpine sable
tough hatch
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so why do u insist that a=17 instead

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whereas c=17

alpine sable
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But the hypoteneuse is already given, one second let me send the equation before it got solved

tough hatch
alpine sable
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So I already have the hypoteneuse

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I need to calculate the opp

tough hatch
#

so you are finding the length of the shorter side

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you need not use angles even, since the triangle is a right triangle

alpine sable
#

yeah

tough hatch
#

a^2+b^2=c^2

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c=17

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either a or b can be 8

alpine sable
#

yes

tough hatch
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assume a=8

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then what do u get

solar widget
#

shit

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thanks man

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makes sense

alpine sable
tough hatch
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yes

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so how do u find b?

alpine sable
tough hatch
#

=????

alpine sable
#

then square root

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yep, 15

tough hatch
#

🙂

#

yes

alpine sable
#

In a right angle triangle are the angles always 90, 45 45?

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all the questions so far have been in this orientation

sharp barn
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Can we solve this with algebra?

rigid smelt
#

yes

tough hatch
sharp barn
#

,rotate 90

ocean sealBOT
sharp barn
#

But the negative part i think i did something wrong

rigid smelt
#

you didnt

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there are no real solutions for x^2+1=-10

sharp barn
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But u cant square root negatives right?

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cant

alpine sable
rigid smelt
#

ok we should move

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this channel is occupied

sharp barn
#

Kk

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Where

tough hatch
#

here you use trig ratios

alpine sable
#

let's move there

plucky slate
#

hello

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if I want to evaluate the formula in normal plot (x, y)

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formula of line i use normal formulas

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like f(x) = ax + b

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when I do such on log scale x I go f(x) = alog(x) + b

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and what about when x axis is the square root scale

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will it be f(x) = a*square(x)+b?

tawny totem
#

Can someone help me pls

#

I stuck on this question

ocean sealBOT
placid zinc
#

Which one is it?

tawny totem
#

@placid zinc 5)

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Here is my attempt

placid zinc
#

What book btw?

tawny totem
#

Its my professor book,there no answers at the back but here is some context

placid zinc
#

Zτ = ∂/∂z + 1/2 τz'
Zτ' = ∂/∂z - 1/2 τz
Using ' for overbars haha

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And it looks like (a, b) = ∫ ab dx over the entire domain

tawny totem
#

I know that

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how do you solve 5) @placid zinc haha

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if you can

placid zinc
#

I'm looking to just simplify the left, and simplify the right. They should come out to the same thing. Does that work?

tawny totem
#

No,i tried :/

tawny totem
placid zinc
#

Ah I see

alpine sable
#

can someone explain the steps taken to arrive to the answer? thanks!

surreal meadow
#

factor out I(s)

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the rest is just moving around terms like usual

small holly
#

how do i do this

vale wigeon
#

make a diagram

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it should become clear

alpine sable
small holly
#

i did

c=sqrt(170^2+320^2-2(70)(320)cos71)
c=342m
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but c=310m

vale wigeon
#

70? did you mean 170?

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,calc sqrt(170^2 + 320^2 - 2 * 170 * 320 * cos(71*pi/180))

ocean sealBOT
#

Result:

309.6420268553
small holly
#

ohh

vale wigeon
#

also

small holly
#

oops my bad

vale wigeon
#

since you had the calculations

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you really really should share them

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the way you asked the question it appeared you didn't know how to even start

small holly
#

oh alright ill do that next time

#

ty

vale wigeon
#

do that all the time for all future problems. share all the progress you have made even if it led you to the wrong answer

small holly
#

alright

split slate
#

How would one do this?

dawn wraith
#

Use the law of cosines bud

split slate
#

Gonna quickly google that

dawn wraith
#

Law of cosines*, sorry.

small holly
#

i cant do a), i did

cosC=(9.5^2+8^2-15^2)/2(9.5)(8)
cosC=0.4654...
   C=cos^-1(0.4654...)
   (I made a triangle BCD, D is left horizontal of C to the B line and named the bottom right angle theta)
   theta=117.74000/2
   theta=58.87 degrees
   ∴ bearing from B to C = 148.87 degrees

but the answer is 145.9 degrees

vale wigeon
#

is CD meant to be perpendicular to AB?

small holly
#

no

surreal meadow
#

@small holly what is the bearing from B to A?

small holly
#

180

surreal meadow
#

good

#

and can you somehow find angle ABC?

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because if you can, you should be able to construct an equation for the bearing from B to C with that information

small holly
#

yeah i can

#

ill try do that and see if i do it right

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yay i got it correct

#

ty

surreal meadow
#

👍🏻

tawny totem
#

Advanced Textbooks in Mathematics
The Wigner Transform
https://doi.org/10.1142/q0089 | May 2017
Pages: 252
By (author): Maurice de Gosson (University of Vienna, Austria)

#

Anyone has this book

#

Can someone DM me pls

#

Lib gen doesnt have it

alpine sable
#

I need some help with part c of this question

split slate
# split slate

Sorry if it seems dumb, but I still haven't been able to do this...

#

Even after trying the law of Cosines

surreal meadow
#

can you show your work?

split slate
#

In ∆ABC, a = 10, b = 11, c = 13. Find the 3 missing angles (2 d.p).

#

Here's what I tried to do:

alpine sable
surreal meadow
alpine sable
#

Ok

split slate
#

$13^2 = 10^2 + 11^2 - (2\times10\times11) \times cos(x)$

ocean sealBOT
#

HappyAlt

surreal meadow
#

\cos{x}, for future refrence

#

but yes

#

did you do anything else?

split slate
surreal meadow
#

oh sorry

split slate
#

That's all I've tried so far

surreal meadow
#

that image is wrong

split slate
#

And if I put it in my calculator

#

Am I doing this wrong?

surreal meadow
#

this: $13^2 = 10^2 + 11^2 - (2\times10\times11) \times cos(x)$

split slate
#

Like...

ocean sealBOT
#

maximo

surreal meadow
#

implies that x is opposite of the side length 13

split slate
#

mhmm

#

But it's the opposite of 11

#

I see that now

fading shadow
#

Need help with q15

#

This is my progress for (a) so far

alpine sable
#

yo

#

can someone please help me!

#

Online learning kinda sucks!

#

Well not kinda, it sucks

indigo jetty
fading shadow
#

@indigo jetty stuck

indigo jetty
#

open up the brackets

#

then simplify

split slate
surreal meadow
#

awesome 🙂

fading shadow
#

15b still having problems tho

indigo jetty
#

for 15b u have two choices: calculus, or completing the square

fading shadow
#

Worksheet is on related rate of change so I gotta do by calculus

indigo jetty
#

then go forit

fading shadow
indigo jetty
#

yup, then express x in terms of k

split slate
#

Sorry

indigo jetty
#

then sub that value of x back into the expression for A

split slate
#

Didn't realize channel was occupied

fading shadow
#

I got A in terms of K now

indigo jetty
#

that would be the answer

fading shadow
#

For part c I got dA/dt = dA/dx ×dx/dt

indigo jetty
#

ok

#

so your task is to find dx/dt

#

You know dA/dt, which is given in the question

#

so now you have to figure out the value of dA/dx

fading shadow
#

If my answer for k is 1 doesn't that mean dA/dx = 0

indigo jetty
#

you are not supposed to solve for k

#

so basically find the value of dA/dx at x = 1/2

#

that 1/(2k) only applies to the previous part, where dA/dx is a minimum, but we are not told that dA/dx is a minimum for this part

fading shadow
#

They want the answer in K right

indigo jetty
#

yes

fading shadow
#

I missed out the 2pi

indigo jetty
#

yup correct

#

well done

fading shadow
#

Thks a lot of the help 👍

indigo jetty
#

👍

split slate
#

This is the diagram I drew for it:

timber granite
tough hatch
#

dont post your question on top of someone else's recently posted one

split slate
surreal meadow
#

looks good

split slate
#

And so are the sides?

#

So... would I do: tan(9°15') = 112/x

#

?

surreal meadow
#

that works

split slate
#

Oh well

#

Why does this make a difference though?

#

One is negative, the other is positive

surreal meadow
#

radians vs degrees

split slate
#

Ahhh

#

Ok

#

That makes a lot more sense now...

#

Thanks!

surreal meadow
#

np

tough hatch
split slate
#

Like MS Paint if you're on windows or screen sketch, anything (including paper)

ocean sealBOT
split slate
#

That would've made it a bit easier to understand

#

Thanks for the illustration and your time!

surreal meadow
#

it says angle of depression though, no?

split slate
#

True

#

But what they just did is kinda the same thing

#

Angle of elevation would be different to the 9°15'

#

It's still in the corner that's going down, so in my opinion, still valid

#

But, you probably know more, so I won't argue too much

tough hatch
#

hmm, i doubt they would be the same answers

surreal meadow
#

they are not

#

take this

#

theta ($\theta$) does not equal 9 15'

ocean sealBOT
#

maximo

tough hatch
#

nvm, my diagram is also wrong

surreal meadow
#

unless 9 15' is = 45 degrees, but i don't think it is

tough hatch
#

editing.

split slate
#

9°15' = 9.25°

#

Also, another question has risen

#

I figured out a to be 176.4m

#

But now, would b just be 176.4 - 24?

tough hatch
surreal meadow
#

that is the same diagram

tough hatch
#

same diagram but correctly labeled angle of depression

split slate
surreal meadow
#

how is this incorrectly labeled?

tough hatch
#

i did not say yours was incorrectly labeled

surreal meadow
#

this is his

digital raft
#

hey , anyone familiar with python ?

surreal meadow
surreal meadow
digital raft
#

@surreal meadow already read them i just want to know if its possible to help with python on here

#

as its maths related

surreal meadow
#

you clearly didn't

tough hatch
#

dont ask to ask

surreal meadow
#

this channel is in use

tough hatch
#

lol

surreal meadow
#

don't ask to ask

digital raft
#

okay

surreal meadow
#

go reread them and ask again 🙂

surreal meadow
surreal meadow
split slate
split slate
#

I just didn't think it could a typo

#

But yeah

#

Thanks!

tough hatch
small holly
#

i need to find the area of this. I did

A=1/2x5x6xsin65 (half of the shape's area)
A= 13.59461681m^2

then i got the angle of the 65 degree's opposite corner:

cos0=(4^2+2.5^2-13.59461681^2)/2(4)(2.5)
cos0=0.9899542372
   0=cos^-1(0.9899542372)
   0=8.128180311 degrees

after that i got the second half of the shape:
1/2x4x2.5xsin8.128180311
sacred marlin
#

@lofty stump

arctic laurel
#

Hey so guys, we got a small project to work on for school, i understand help with projects and such may not be allowed, but i need help in understand what the fk a question is asking of us to do not really needing help with calculations.

#

I need help with the bridge design 2, part of the project, i don't understand if for the right side it will also decrease by 55% of the previous and if shortest one is to be atleast 1 m long aswell, or are they leaving it up to us to decide what we want to do with it.

tough hatch
arctic laurel
#

❤️ purple light

unborn dome
#

can someone help me out on this?

dull oak
#

Someone help pls

dull oak
#

since i will sleep now and wake up, this message is likely to be lost

#

please dm me any help if u are going to do so thank you!

tepid jungle
#

what does the d on top of the = sign mean?

subtle mantle
#

it probably means equal to by definition

alpine sable
#

its 1/cos im dumb nm

alpine sable
#

bye bitches

covert berry
#

Wow, everyone posts in one channel.

fossil shoal
#

Hi, I'm trying to understand a solution to a fluiddynamics problem. We basically have polar coordinates $(r,\theta)$ whereas we have rotational symmetry i.e. basically $\frac{\partial}{\partial \theta}=0$. We want to find some velocity $\vec{u}=(u_r(r), u_\theta(r))$.

The solution at one point does
[
0 = \frac{\partial}{\partial r} \bigg(\frac{1}{r} \frac{\partial }{\partial r}(r u_\theta) \bigg) \quad \Rightarrow \quad u_\theta = \frac{1}{2} C_1 r + \frac{C_2}{r} \tag{1} ]

I'm trying to see how I'd get to that systematically without "starring at it and just guessing it".

My approach is: $\frac{1}{r} \frac{\partial }{\partial r}(r u_\theta) = C$ whereas $C$ is some constant. We get

[
u_\theta + r\frac{\partial}{\partial r} u_\theta = rC \tag{2}
]

that's an inhomogeneous Euler-Differential equation right? So my approach would be to first solve the homogeneous case and the the particular case and then "add them up" but that seems way too involved for this lecture (they basically don't expect people to solve anything beyond sep. of variables).

So my very simple question is: Is there some easier simpler way to solve it, like some trick I don't see right now? Thanks 🙂

ocean sealBOT
#

balance

wispy olive
#

What does [] mean in Geometry?
Does it mean perimeter or area?

#

Like for example here.

#

What do these mean.

#

Anyone?

oak chasm
wispy olive
#

Okay.

#

Thanks!

oak chasm
#

No problem.

solid fox
#
what are the odds of getting tails on any of 10 coins
fast patio
#

i thing its called complementary odd or something?

#

you either get at least one tails or no tail at all

#

so:
P(at least one tail)+P(no tail at all)=1
P(at least one tail)=1-P(no tail at all)

proper quail
#

a^x=b^y to a=b^(y/x)

#

how does that work

#

im trying to understand a proof

#

wait i can use latex

#

How do you get from
$a^x=b^y$
to
$a=b^{y/x}$

ocean sealBOT
#

Epicmania

fast patio
#

i dont think you do...

#

im trying to think a situation where this is false

proper quail
#

its in a proof in an aops textbook

#

so im just trying to understand it

fast patio
#

maybe you should use log?

minor heath
proper quail
#

its proving a log property

ocean sealBOT
#

G3oG0dly

minor heath
#

can you continue from there

proper quail
#

yeah

#

i get it

#

thanks

#

you multiply both exponenets by 1/x and get $a=b^{y/x}$

ocean sealBOT
#

Epicmania

manic glade
#

this is correct right?

minor heath
#

then multiply using law of exponents

tough hatch
wind zinc
#

Hello

candid dagger
#

Two equations have at least one solution in common. How can I translate that information into math stuff?

#

My english is pretty bad lol

#

The equations contain a parameter , so I tried to make the solutions equal, but i dont know how to deal with the roots

#

I realized I could make delta=0 and get one of the answers, but I dont know how to get the second one

cinder sonnet
#

i see this one not on use so imma proceed
this is conjugate question, rationalize it

I just learnt this today but still bad at it. Im stuck on after i multiply the numerator [ 1-√2 ] * [ 1-√2] (result of denominator conjugation [1+√2] )which will get
1 -√2 - √2 + 2 and i have no clue on how to solve -√2-√2

sorry for the inconvenience and i appreciate your help.
i have whole week so deadline is not a problem and maybe i could learn myself by that time. but your help might fast forward it.

ocean sealBOT
#

SubGui

astral dagger
#

I meant 6/-1, there's a typo

candid dagger
#

Wow good tex skills

astral dagger
cinder sonnet
#

Thanks a lot, i'll learn from this

astral dagger
#

as you have learned

#

but I still prefer to do like I did

cinder sonnet
#

alright i'll find my preference, thanks

candid dagger
feral crypt
#

If you make the two equations equal to each other and then solve for x

cinder sonnet
#

sorry i did not realize it was a question, pardon the intrusion man

candid dagger
feral crypt
#

Can you show the problem?

candid dagger
#

Yeah it's not in english, I'll try my best to translate it

feral crypt
#

But do you have the equations?

candid dagger
#

"For which values of "a" do the two equations x²+ax+2=0 and x²-x-2a=0 have at least one common solution?"

feral crypt
#

Ok let me try

candid dagger
#

Thanks

misty mortar
#

Is there an error to this problem?

feral crypt
#

I think that’s right

candid dagger
#

That's one of the solutions

#

Pretty interesting how you got it

feral crypt
#

Hope that’s helps 😄

candid dagger
#

Oh I think I got it

#

You divided by (a+1), implying that a must not be -1

feral crypt
#

Actually a can be -1

candid dagger
#

And -1 is actually the other solution

#

Hmmm

#

Enlighten me

feral crypt
#

Just by plugging -1 into the equations we will see that they are equal

candid dagger
#

Yeah, to show that tho? I did it by calculating the 4 solutions of the two equations separately, then assuming delta=0 and solving

#

Does it make sense?

#

And delta>0 is the case you showed

#

Via the system

feral crypt
#

I see

#

Well this is how I would’ve gotten to -1

candid dagger
#

Yea makes absolute sense

feral crypt
#

How were you able to calculate 4 solutions for the equation?

candid dagger
#

I think I used the wrong word

feral crypt
#

Did you just plug into the quadratic formula?

candid dagger
#

Yrp

#

Yep

#

I had got -1 as my first result but I didnt know what to do next

#

So thanks a lot

feral crypt
#

Well the question is just asking for 1 solution no? So I guess you had it 🙂

candid dagger
#

I would have got half a point I guess lol, its asking "which values"

feral crypt
#

Ahh I see. Well glad I could help 😁

candid dagger
#

Thanks and bye

#

I have another completely unrelated question.
i⁴=1
Take the fourth root of both sides
i=1

I dont know pretty much anything about how imaginary and complex numbers work, but what's wrong here?

#

Or maybe I dont know how roots work lol

feral crypt
#

So i is equivalent to sqrt(-1)

#

If I put the sqrt(-1) to the power 4 than it simplifies to 1

candid dagger
#

And it is wrong

#

Why

feral crypt
#

Well I always equals sqrt(-1)

glass lichen
#

you're solving $z^4-1=0$ with a root already plugged in

ocean sealBOT
glass lichen
#

$z=\pm 1, \pm i$ are all the solutions to that

ocean sealBOT
candid dagger
#

Oh my bad I'm treating i as a normal variable

#

I think that's the mistake

feral crypt
glass lichen
#

yes

candid dagger
#

Ye thanks guys

glass lichen
#

$z^4-1=0 \ (z^2-1)(z^2+1)=0 \ (z-1)(z+1)(z-i)(z+i)=0$

ocean sealBOT
random pelican
#

quick question, what is (2a+3b)² expanded? is it (2a+3b) or (2a-3b)? and with (2a-3b)²?

alpine sable
#

$4a^2+6ab+6ab+9b^2$

ocean sealBOT
#

Lambdalo

alpine sable
#

for (2a+3b)²

random pelican
#

oh, okok, ty
but when i want to use the foil method, to expand it do i invert the signs of the 2nd parentheses?

alpine sable
#

foil?

#

first outside inside last?

random pelican
#

what should be minus

alpine sable
#

nothing

random pelican
#

oh, okok

#

ty

alpine sable
#

(a+b)² = a²+ab+ab+b²

random pelican
#

like this right?

alpine sable
#

for mutliplication (-n) times (-n)= n but negative times negative = positive you can't use that principle for n*n=-n

#

$(-n) x (-n)=n,n x n ≠ -n $

#

$(-n) x (-n)=n,n x n ≠ -n $

#

alright it doesn't want to compile

alpine sable
random pelican
#

okok, ty

alpine sable
#

no problem

willow wadi
#

hi guys

alpine sable
willow wadi
alpine sable
#

oh then my bad nevermind

halcyon geode
willow wadi
#

(4√3 I + 29j)

#

this what i got

halcyon geode
#

sounds about right

willow wadi
#

thanks

#

Hey 1 more ques

#

i need help with this

feral crypt
#

Calculate vertical and horizontal forces then use pythag

livid knot
#

can someone help me with calculus (limits and continuity)

feral crypt
#

This room is busy rn

livid knot
#

Ok

willow wadi
feral crypt
#

I'm checking now

#

Sorry I’m a little slow lol

alpine sable
# livid knot

do u need answers or like.. proper solved solutions ?

livid knot
#

@alpine sable i just need help understanding the 3rd question

alpine sable
#

okaY

glass lichen
#

$\lim_{x\to 0}\frac{3^{\sin(x)}-3^{\sin(0)}}{x-0}$

ocean sealBOT
feral crypt
livid knot
#

woah whats that

feral crypt
glass lichen
#

rewriting the 3rd limit

livid knot
#

okay thanks

willow wadi
#

ty

livid knot
#

@glass lichen would you use the L'Hopitals rule for this quesiton 3?

glass lichen
#

no

livid knot
#

oh I used L Hop for question 2

glass lichen
#

Ok well you can, but you dont have to L'H either 2 or 3

livid knot
#

can you tell me how to solve it without using L'H

glass lichen
#

solve 2 or 3?

livid knot
#

just 2 for now and then ill attempt 3

glass lichen
#

Ok $\lim_{x\to 0}\frac{\sin(x^2)}{x}=\lim_{x\to 0}\frac{\sin(x^2)-\sin(0^2)}{x-0} \ =\dv{x}\sin(x^2)|{x=0} \ =[2x\cos(x^2)]{x=0} \ =2(0)\cos(0)=0$

feral crypt
livid knot
#

so that would be the final answer?

glass lichen
#

no clearly not

livid knot
#

would it still be sin(x^2)

#

just making sure i got it right using L'H

ionic jewel
#

this is lhopital with extra steps

ocean sealBOT
glass lichen
gaunt magnet
#

karen alert

ionic jewel
#

fair enough, different method but they both end with taking the derivative of sin(x^2)

glass lichen
#

then yes, in that regard

gaunt magnet
#

can i get this chanel

#

channel

glass lichen
#

No

gaunt magnet
#

😋

glass lichen
#

it's in use

gaunt magnet
#

by who

glass lichen
#

unless Yang is done w/ it

#

there's also 9 other channels

gaunt magnet
glass lichen
#

10 total, 9 other

livid knot
#

so how is question 3 different from 2

glass lichen
#

you can do 3 with the same process I demonstrated, recognizing the limit as a derivative

livid knot
#

its the same concept right?

glass lichen
#

yes

livid knot
#

okay thanks

gaunt magnet
#

ok

#

hi

#

Resolve a force of 200N in the direction S 22 degree E into its regular componets

unkempt prism
#

Hi

tranquil parcel
#

Hi

strange oasis
#

@gaunt magnet Use sin and cos

gaunt magnet
strange oasis
#

what did you get?

gaunt magnet
strange oasis
#

Is the angle 22 degrees east of south or 22 south of east?

#

double check that

strange oasis
#

then you're right

gaunt magnet
gaunt magnet
normal idol
#

Oh, sorry 😅

strange oasis
#

@gaunt magnet yes

willow wadi
#

Hey

#

guys

#

so

#

question

glass lichen
willow wadi
glass lichen
#

yes.

willow wadi
glass lichen
#

Given I said yes...

willow wadi
#

check how to get help

willow wadi
gaunt magnet
#

better then yes

glass lichen
ebon quail
gaunt magnet
#

lol

willow wadi
glass lichen
#

Not sure why you also feel the need to constantly harass me whenever you get the chance

gaunt magnet
livid knot
willow wadi
#

use another channel

livid knot
#

alright

willow wadi
#

A mass of 60kg is suspended from the ceiling by ropes.The angles between the ceiling and the ropes are 31 degree and 59 degree.Determine the tensions in the ropes include a diagram.

The acceleration due to gravity is 9.8m/s^2
Include a diagram

willow wadi
wary stream
#

First draw an FBD

heavy spear
#

i think you are going to use a calculator for this one since you are prob going have to do sin , cos , tna

#

tan

#

so ye 🙂

#

my input i dont know anything else though

willow wadi
wary stream
#

Yes, that's the diagram you're going to but not the FBD to use

wary stream
# willow wadi

Now make a FBD then equilibrium equations, sum of forces in the x and y direction

random pelican
#

quick question, what is 2 * x^2

wary stream
#

Exactly that

random pelican
#

ok, ty

willow wadi
#

what do i do now

wary stream
#

That m is wrong

willow wadi
wary stream
#

Use the proper m

#

Then equilibrium equations

willow wadi
wary stream
#

Do you know what an equilibrium equation is?

wary stream
#

Not chemistry, physics equilibrium

willow wadi
wary stream
#

Sum of forces

#

In the x and y direction

willow wadi
#

ok

#

ill try

light quartz
#

logx+logx is 2logx right

#

right?

#

and how is derivative of 1/x -1/x^2

glass lichen
slender forge
light quartz
slender forge
#

Use power rule

minor dagger
#

can someone show me what c/cos(45) looks like on the unit circle

craggy steeple
#

#11 pls help

placid zinc
craggy steeple
#

can you help me with #11 too?

placid zinc
#

Do you know what the first term is?

craggy steeple
#

uhh

#

yes

#

isnt it 38?

#

wait no

#

its 28

#

the first term is 28

placid zinc
#

Right! Then the second term:

craggy steeple
#

oh yeah i knwo that part

#

but i need help with the explicit

#

formula part

placid zinc
#

28 + 10(n - 1)

wary stream
placid zinc
#

Memorize this haha

craggy steeple
#

uhh

placid zinc
#

Or, at least understand why it works by plugging in a few points

craggy steeple
#

doing

#

a1 + d(n-1)

#

is that how u got

#

it

#

also, i dont think thats explicit

craggy steeple
placid zinc
#

So I just have a lot of experience with this, and can sus out the form haha. You will be able to too

craggy steeple
#

like plug it in

#

so i can see

#

the reference

placid zinc
#

That is explicit

craggy steeple
#

28_10(n-1)

wary stream
#

All you do is plug in a1 and d into the formula

craggy steeple
#

ok

#

so a1 is

#

28

#

and so it would be

#

28+10(n-1)?

wary stream
#

Yes

craggy steeple
#

ok

#

thank you!

willow wadi
#

Hi

#

this question i did it

#

but

#

A mass of 60kg is suspended from the ceiling by ropes.The angles between the ceiling and the ropes are 31 degree and 59 degree.Determine the tensions in the ropes include a diagram.

The acceleration due to gravity is 9.8m/s^2
Include a diagram

#

i made a diagram

#

then

#

so i got

#

T_1 cos31+ t_2 cos59=0

#

Pls someone tell me if i made any mistakes

hidden seal
#

It looks good friend

#

Use the second equation to get a nice expression for T_1 in terms of T_2 and plug that in the first equation

hidden seal
#

Yes. This equation tells you that T1 is exactly $\frac{\cos(59)}{\cos(31)}\cdot T_2$

ocean sealBOT
#

navessss

gaunt magnet
#

,w cos(59)/cos(31)

jolly lark
#

What percentage is 2,800 out of 10,300? *

willow wadi
#

go to another channel in use

willow wadi
hidden seal
# willow wadi and then?

Since you have T1 in terms of T2, you can plug in whatever expression you got for T1 into the first equation

#

Then you solve for T2

#

Then you plug in the value you got for T2 into the expression you got for T1 and that should be it friend

hidden seal
#

Plug both values into your original equations, and the equalities should hold if you did it right

hidden seal
#

its ight I've been in your place many many times before believe me lmao

hidden seal
#

Plug in the values you got in those, and you should get something like 0=0

#

that's how you check these things

willow wadi
hidden seal
#

No, no

#

So,

#

When you see an expression of form x=k, you're stating that x and k are the exact same object. When you know, for example, that x=123, you can use the symbols "x" and "123" interchangeably. They are two different names for the same thing.

#

So $T_1\cdot\cos(31) = 645.1\cdot \cos(31)$

willow wadi
#

ohh

ocean sealBOT
#

navessss

willow wadi
#

,w T_1\cdot\cos(31) = 645.1\cdot \cos(31)

ocean sealBOT
static glen
#

Hey

#

Im rlly confused on this

#

So what i think its that its between the height

#

or yearly income

#

im not sure tho

sleek elbow
#

I would tend to say yearly income

#

cause I feel like height is less spread out

static glen
#

hm

#

well

sleek elbow
#

not sure tho cause I didnt do that in school yet

undone pond
#

what is the result of 5 - 4 x 12

sleek elbow
#

if not this should help

undone pond
#

ok ty

noble sinew
static glen
noble sinew
#

yes

sleek elbow
#

how so? im curious

static glen
#

Same

noble sinew
#

height is a common example of something being normal distributed

sleek elbow
#

and income isnt?

noble sinew
#

no?

sleek elbow
#

okay

glass lichen
#

Height has a clear mean value based on demographic and history of the people

static glen
#

oh yeah

#

because some people have a much larger income then others?

#

while someone being much taller than an average is rare?

glass lichen
#

yes, extreme heights are rare genetic mutations

static glen
#

ok tysm

sleek elbow
#

stretches far to the lower incomes, interesting

cinder lily
sleek elbow
cinder lily
#

oh ok

willow wadi
#

hello

#

this ques

#

having alot of troubles

#

😭

#

this question is pain pls help

glass lichen
gaunt magnet
willow wadi
# glass lichen can you write OB in 2 different ways?

mark a point centrosymmetric to O relative to B
we can call it O'
then O'A||OC and AC|O'C
AOCO' is a parallelogram
then express OO' in terms of OA and OC and find OB knowing that the diagonals of a parallelogram intersect in the middle
hang on you will need a better argument to prove the parallelogram
prove that triangles OBC and ABO' are congruent, and prove ABO and BCO' are congruent (both pairs side-angle-side)
then |AO|=|CO'| and |OC|=|AO'| (segment lengths, not vectors)
AOCO' is a parallelogram

glass lichen
#

I mean yeah, make a geometric argument, however you can do it in like, 2/3 lines of quick algebra

willow wadi
glass lichen
#

yeah, prove algebraically

willow wadi
glass lichen
#

you took a geometric approach

#

not an algebraic one

willow wadi
glass lichen