#help-0

1 messages · Page 695 of 1

fallen sentinel
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?

past sundial
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Like I know it’s infinatly small, but idk about large

ember lava
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this is a test

fallen sentinel
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I just want a different approach to solve it

ember lava
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@sullen karma

fallen sentinel
ember lava
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what should i do

ember lava
past sundial
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Simple 😄

ember lava
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@fallen sentinel send an ss of entire screen

past sundial
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If they don’t have proof, u may administrate punishment

past sundial
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But if they are telling truth, that shouldn’t be a problem

ember lava
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hmm

past sundial
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I THINK that might count as valid proof, they got from another source, so I think that’s fine

ember lava
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ok ig

past sundial
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Cause it doesn’t seem they cropped it themselves

fallen sentinel
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So it's a question from a grp .. of my friends

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And so I ended up with this q.

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I'm Indian.. grp is for IIT jee people

ember lava
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even im an indian

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u preparing for jee?

fallen sentinel
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Yes

ember lava
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which grade are you in

vagrant kayak
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me

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too

fallen sentinel
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12th .. 2022 my first attempt

ember lava
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me too

fallen sentinel
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Nice

ember lava
vagrant kayak
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i am in 8th

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studying for jee

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concepts

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HELP ME

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pls

ember lava
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..

vagrant kayak
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solve pls

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i hate maths in jee

ember lava
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..

crystal tapir
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is this yr 12?

ember lava
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do u want soln of all questions?

vagrant kayak
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yes

ember lava
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ok

vagrant kayak
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be quick pls

fallen sentinel
ember lava
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but i shouldnt tell u the answer

vagrant kayak
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why?

ember lava
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i'll help you get the idea

crystal tapir
vagrant kayak
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its not my test

ember lava
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you should also try solving it

crystal tapir
ember lava
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so i'll just guide you

vagrant kayak
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ok!

ember lava
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ok

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so

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for the 15th one

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so lets ignore the lines for now

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so how many points of intersection will be there for circles?

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2 are concentric

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@vagrant kayak

vagrant kayak
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i-

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idk

ember lava
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concentric will not have any point of intersectiion right?

vagrant kayak
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yes

ember lava
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ok

vagrant kayak
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Omg exam in 10 mins

ember lava
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so now take another circle and draw it such that it will intersect both the concentric circles

vagrant kayak
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pls tell the answers

ember lava
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i

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i cant solve all in 10 mins lol

vagrant kayak
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solve how much u can

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pls

ember lava
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but

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if i just tell you the answer

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whats the point

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you anyways wont get it

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huh

vagrant kayak
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atleast they will come in exam

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i mean'

ember lava
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how can you be sure theyll come in exam

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only these questions

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sus

vagrant kayak
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teacher said

past sundial
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I guess summarize and lead miracle to answer, but don’t tell the answer

ember lava
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hmm but each question will take quite some time explaining

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xD

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idk what to do lol

vagrant kayak
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ok tell me

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how to find the even divisors of n

past sundial
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Use time to explain now, don’t talk, explain, if time is short, best to explain then to talk

ember lava
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k

past sundial
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Explain as in lead, but not give direct answer

ember lava
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bruh

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u shud be helper

past sundial
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I don’t know what u are talking about so I can’t really help lol

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I’m just taking notes on infinity and pondering about infinity lol

ember lava
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@vagrant kayak draw circles and make them intersect the concentric circles. now draw lines that intersect the circles

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do something like that

vagrant kayak
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ok

ember lava
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p&c sucks

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lol

fallen sentinel
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Lol I have given up on PnC

ember lava
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p&c comes in jee

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study it

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lol

fallen sentinel
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These questions are still bit easier... but I literally haven't solved any PnC problem in months ..

ember lava
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...

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practice them

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try solving them

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im sure you can do it

vagrant kayak
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i am gonna get bad marks in maths

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for sure

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:((((

ember lava
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;-;

vagrant kayak
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;9

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😭

frail anvil
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Is anybody is of Class 9 or below?

noble crypt
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just ask your question if you have one

rich basin
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I was wondering what is wrong with my query

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,w solve ( 4 choose 3) * (3 choose 1) * (2 choose 1) + (4 choose 2) * (3 choose 2) * (2 choose 1) + (4 choose 2) * (3 choose 1) * (2 choose 2) + (4 choose 1) * (3 choose 2) * (2 choose 2) + (4 choose 1) * (3 choose 3) * (2 choose 1)

ocean sealBOT
rich basin
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,w solve (4 choose 1) * (3 choose 3) * (2 choose 1)

ocean sealBOT
rich basin
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(4 choose 1) * (3 choose 2) * (2 choose 2) + (4 choose 1) * (3 choose 3) * (2 choose 1)

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,w solve (4 choose 1) * (3 choose 2) * (2 choose 2) + (4 choose 1) * (3 choose 3) * (2 choose 1)

ocean sealBOT
rich basin
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,w solve (4 choose 2) * (3 choose 1) * (2 choose 2) + (4 choose 1) * (3 choose 2) * (2 choose 2) + (4 choose 1) * (3 choose 3) * (2 choose 1)

ocean sealBOT
vivid breach
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So, to solve the following a very convinient sol. has been given here : https://www.youtube.com/watch?v=ePIKlri8FYg

Instead of such calculations and me being in 8th grade I just verified that; lets assume 10 before the infinity radical then;
10x10 = 100 and sqrt.100 = 10 continuing this process the last ans comes as 10*10 = 100 hence, i replied for the following as x = 100 though the ans, was correct can we appreciate this as a solu. for such similar questions, also maybe this wont work with nums. in series such as the 2nd example from the vid. mentioned above,
where a series of nums. (3, 5) were used

A version of this problem appeared in a math competition for 16-17 year olds. Can you figure it out? Thanks to Abdelhakim in Algeria for suggesting this problem!

Subscribe: https://www.youtube.com/user/MindYourDecisions?sub_confirmation=1

Playlist to watch all videos on MindYourDecisions: https://www.youtube.com/playlist?list=UUHnj59g7jezwTy5G...

▶ Play video
distant violet
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Geyo

ornate grove
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Inh2o to mmscf formula

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?

thorn kindle
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10sqrtx=x

100x = x^2
x=0
x=100

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,w 10sqrt(10sqrt(x))=x

thorn kindle
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100 checks out

thorn kindle
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Are we to assume Z+

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Wait no nvm thats not possible

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Assume a=b=c

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3x=3x^2=1

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No i dont think that works nvm

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,w expand (a+b+c)^2

thorn kindle
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2(ab+ac+bc)=0

fallen sentinel
thorn kindle
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Oh damn thats it

teal epoch
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Are we giving the answer now

thorn kindle
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Fun problem

vagrant kayak
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just finished my exam

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GUESS WHAT

thorn kindle
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Gg

vagrant kayak
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almost every question is p&C

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EEEEEEEE

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IT WAS THE ONLY TOPIC I DIDNT STUDY'

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UGHH

teal epoch
thorn kindle
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P&C?

vagrant kayak
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p&C

teal epoch
thorn kindle
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Lmao i hate that

vagrant kayak
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ME 2

vagrant kayak
thorn kindle
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Its the only basic math topic i was never taught in school

vagrant kayak
thorn kindle
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I was never taught it

teal epoch
thorn kindle
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But its kind of intuitive and you can brute force it if all else fails

vagrant kayak
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bruh

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they taught me basics of pnc in 7th grade

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now i am in 9th

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still dont even understand the basics -_-.

ivory otter
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can i use this channel?

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guess i can

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So

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if i get tan 270

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what do i do in this case

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since its undefined

ionic jewel
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,w tan(270 degrees)

ionic jewel
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you say undefined

ivory otter
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but

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ok wait check this

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show that: $\tan(v - 270) = - \frac{1}{\tan v}$

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how do i add space

ionic jewel
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don't put the words in the dollar signs

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and also it's \tan

ocean sealBOT
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MEOWBRO 父

ivory otter
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if i would want to prove this

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ill get undefined values

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or nooo

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waait

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i get it

ionic jewel
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the other side is undefined at the same points

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so it's fine

ivory otter
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ye

ionic jewel
ivory otter
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no idea how im supposed to solve this

ionic jewel
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what's the tan(a+b) formula?

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I'm willing to bet you just use that

ivory otter
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i did

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i used the tan(a-b)

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formula

ionic jewel
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and what did you get

ivory otter
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lemme get my phone and take a pic

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instead

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no energy to use latex

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lol

alpine sable
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I found the maximum possible no. of student using circle venn diagram.

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how to find the minimum no. of student

ionic jewel
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max I assume you got 85?
for minimum I get 60, but I'm not completely sure that's right

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and sorry meowbro, idk how to finish your problem

hasty hedge
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Sin 270 = -1

ivory otter
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<@&286206848099549185>

alpine sable
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solved using the venn diagram, found i drew it wrong

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min. 48

teal epoch
strong furnace
# ivory otter

tan(v-pi)=tan(v) , tan(pi/2-v)=cot(v) , cot(x)=1/tan(x) , this is what you need

ivory otter
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Like cot and sec

thorn kindle
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Sin(v-270)/cos(v-270)

cos/-sin

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Use unit circle

ivory otter
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Interesting

ionic jewel
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10 in all 3, then the best you can do is have everyone else in two clubs

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oh

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i see

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i can't do mental math this late

ornate grove
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Can I convert inh2o to mmscfd

vale wigeon
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mmscfd?

rocky cape
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x = log3(6561)

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The 3 is small and is on the bottom of the log

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Does anyone know how to do this?

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I can't find it anywhere, they are always slightly different.

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Here's the screenshot.

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How do I solve these two ?

teal epoch
ocean sealBOT
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Callaway

rocky cape
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Where did the X go

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hm

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other way around

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its ddown arrow

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if that even exists

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like the small number is on the bottom

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oh i got that too

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idk what to do from there tho

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can i put x in the power????????

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damnn

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im doing it wrong then

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i used the solver on graphics calculateor

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thats for X right

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rule 5

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wait no

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ya but idk how to do in the calculator

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but thats the power of be

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B*

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I dont understand 💀

teal epoch
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wait are you new to logarithms

rocky cape
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Nah

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i literally did them like 9 weeks ago

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i just forgot bruh 💀

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i got an exam on wednesday

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algebra + probabibility

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it'll be fine tho

alpine sable
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thanks mate for all the rules

calm rock
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can anyone here help me understand/clarify the concept of the principle argument in complex numbers? im more comfortable with DM's if it helps but im fine talking about it here.

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its less of a question and more of a clarification on a topic if thats allowed. i do not understand the principal argument or how it works. all i know is that it helps somehow with dealing with the multiple angles that arise from computing the angle of a complex number.

alpine sable
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I know if dot product of two vector is 0, then it means both are perpendicular to each other

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but how to make it lie in the plane P ? or verify if it lies in the plane P

lethal stump
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a vector will lie on the plane P if it satisfies the equation for the plane P

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i.e. the v = lambda(6,6,9) + mu(7,8,10)

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soz i can't latex

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umm

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actually let me just see if i can do this q first

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do you have answers @alpine sable

alpine sable
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we get (1, 2, 1)

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and scale it to unit vector by dividing by v/|v| i.e. root 6

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well it lies in plane P, but how can i verify that and what if it does not lie?

lethal stump
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well the way i verified it was by subbing it into the plane eqn

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but i'm more curious as to how you got ur vector in the first place

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because i had to dot product the plane and vector and find a lambda and mu value, which is already enough confirmation that it's on the plane

alpine sable
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dot product should be 0

lethal stump
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yea i got the right answer

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(1/sqrt(6))(1,2,1)

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but i doubt that you would need to confirm it given that you've already dotted the plane and the vector

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unless ur teacher is super pedantic or smth

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in that case you can sub ur vector back into the plane eqn and confirm that it satisfies all three simultaneous eqns

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after you equate the x, y and z components

alpine sable
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How can I justify part (a)?

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For part (b), I think the acceleration is forward, since his cheeks are going back, so wind is hitting against them

lethal stump
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yah you gots it

alpine sable
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But how do I justify part (a)/

lethal stump
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for part a i think you gotta assume that he's experiencing an unbalanced force

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and objects that are moving at constant velocities do not experience any net force

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like if ur in a car and the car is moving at 60kph without speeding up or slowing down, you don't feel like it's movingi

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i.e. ur not experiencing any force

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but then when the car speeds up or slows down you jerk back

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i.e. ur experiencing a force

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because ur acelerating

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*accelerating

alpine sable
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Yeah but we haven't been introduced to forces yet

lethal stump
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wait so ur telling me that you learned acceleration before u learned forces?

meager vault
lethal stump
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damn what is ur science faculty smoking

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no offense

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but srsly wut

alpine sable
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So the acceleration is forward.

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It wouldn't matter that the velocity is forward I think.

slate kayak
blazing crater
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whats 1 + 1?

alpine sable
#

A person standing on the edge of a cliff at some height above the ground throws one ball straight up with initial speed v0 and then throws another ball straight down with the same ini- tial speed. Which ball, if either, has the larger speed when it hits the ground? Neglect air resistance.

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How do I build equations for this?

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y = y0 + v0y * t - 9.8/2 t^2 is the position of the ball at time t, where y0 is the height of the cliff

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So the velocity is y'(0) - 9.8t

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I have no idea how to account for making it fall straight down or thrown up first, though

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<@&286206848099549185>

vale wigeon
#

let $y_0$ be the starting height of both balls and let $v_0$ be the magnitude of the balls' initial velocities (the same for both balls as stated by the problem)

ocean sealBOT
vale wigeon
#

then the equations of motion for our balls are:

$y_1(t) = y_0 + v_0t - \frac12 gt^2 \ \ y_2(t) = y_0 - v_0t - \frac12 gt^2$

dull onyx
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would i ask for help here or is this being used

ocean sealBOT
dull onyx
#

kay nvm

vale wigeon
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@dull onyx this channel is being used. ask in one that's free.

dull onyx
#

sorry!

alpine sable
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How do I know this is true?

vale wigeon
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one's going straight up, the other's going straight down...

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they are subject to the same gravitational acceleration and start at the same height

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all that differs is the direction of their initial velocity

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do you have any objections to this?

alpine sable
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No that makes sense

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So we would be comparing |v_0 - gt| and |-v_0 - gt|

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But when its position equal to 0

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At some time t

vale wigeon
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we would be comparing their velocities at the time of their landings

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these are different

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for the two balls

alpine sable
#

Oh

vale wigeon
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but also i suppose we could cheat a little

alpine sable
#

Yes that is right

vale wigeon
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and avoid the laborious computations

alpine sable
#

How?

vale wigeon
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i'm making a picture, hold on

alpine sable
#

doing it this way (with minimizing the LP) is an overkill. At the moment I am very busy, maybe I can post al solution the next 24 hours

vale wigeon
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the red and black parabolas are the position-time graphs for our two balls

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the solid parts of them, in any case

ember lava
#

but the guy is throwing the ball straight up

vale wigeon
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the horizontal axis is time.

alpine sable
ember lava
#

i have another way of solving it

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nvm

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you go on

vale wigeon
#

do you agree that for any parabola, the slopes of the two tangent lines at the x-intercepts are equal in magnitude (and opposite in sign)?

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if your only objection is that you don't see how it relates to the problem, hold that thought. i'll get to it in a moment.

alpine sable
#

Yes of course, a parabola is a reflection of its other branch across a line going through its vertex

vale wigeon
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okay great

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well now here

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the black parabola is a reflection of the red about the y-axis

alpine sable
#

Yes

vale wigeon
#

yeah so there you have it

alpine sable
vale wigeon
#

the slopes of the tangent lines at all four horizontal intercepts visible in the picture are the same (in magnitude)

alpine sable
#

Why would it be a reflection of the other parabola about the y-axis axis?

vale wigeon
#

.........

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you should have asked this when i said it

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but ok

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$y_2(t) = y_1(-t)$

ocean sealBOT
vale wigeon
#

if we ignore the restriction of t ≥ 0 for a moment

alpine sable
#

Makes sense, thanks

spring harbor
vale wigeon
#

that's the conclusion i've been leading up to.

spring harbor
#

But I thought the one you threw up would have higher speed since the potential energy would be larger than the potential energy of the other ball

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mgh=mv^2 /2

vale wigeon
#

nah

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they start out with the same total energy

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kinetic plus potential

spring harbor
#

Oh I see

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Hmm yeah then I can see them having same speed

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thanks

alpine sable
#

But what about reasoning it like this: The ball thrown directly up has more time to accelerate while coming downwards, since it'll be higher up?

spring harbor
#

yeah but the ball that's thrown down starts with a speed and keeps accelerating, while the other one decreases in speed and once v=0 it starts accelerating

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or something at least from what I just understood

vale wigeon
#

it has more time to accelerate, but that time will be spent getting its velocity to zero and then pointing downward

alpine sable
#

That doesn't bother me now

vale wigeon
#

in fact, once the upward ball falls back to the same height it was thrown from, it behaves identically to the downward ball, only delayed in time

spring harbor
#

actually we can try this out, let's say we're at h=5 and the start v0 = 5m/s and both balls have m=2kg
We get for ball that's going down: 5.10.2 + 2.5^2/2 = 2.v^2 /2
<=> v ~ 11.18 m/s

For the second ball: mgh=mv^2 /2 + mgh
2.10.h = 2. 5^2 /2 + 2.10.5 or h = 6.25
so we get mgh = mv^2 /2 or 2.10.6,25 = 2.v^2/2 or 11.18m/s as well

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damn that's sick

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Physics thinkies

fathom jungle
#

The rules said not to allow 12 or younger than 12

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I'm turning 13 in 6 days so... am I allowed?

vale sapphire
#

unfortunately them's the rules

fathom jungle
#

ok Ill wait then

alpine sable
#

I feel like such a grandma when I read that people on here are like 12 or 13.

storm stirrup
#

Ive been looking over this one question, as self study but I'm not able to figure out how regions in the venn diagram are being wrote as values of x

sleek elbow
#

wtf dude

storm stirrup
#

???

fading citrus
#

thanks

sleek elbow
#

🤔

limpid spade
#

lol

sleek elbow
#

thanks dGhost

fading citrus
#

All good :)

sleek elbow
#

btw am I allowed to ping mods if stuff like this happens? @fading citrus

fading citrus
#

Of course

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Either that or modmail is okay

sleek elbow
#

okay ty

storm stirrup
lament wyvern
#

so (F, G) + (F, G, S) = 25.

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(F, G, S) is x, so (F, G) + x = 25.
(F, G) = 25 - x.

storm stirrup
#

Ohhh, thanks

teal epoch
storm stirrup
#

😆

#

Thx for trying anyways

alpine sable
#

A second ball is dropped down an elevator shaft 1 s after the first ball is dropped. (a) What happens to the distance be- tween the balls as time goes on?

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For ball 1 the distance from ground is y'(0)t - gt^2/2

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For ball 2 it is y'(0)(t + 1) - g(t + 1)^2/2

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Subtracting, we get -y'(0) + gt - g/2

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So as t -> infinity, the distance -> infinity, right?

alpine sable
#

If x is a

prime number, then LCM of x2,x4,and x6 is. Please explain it throughly

thorn vortex
#

$\text{You did an error in the equation}
\text{first ball has:}
y_1 = at^2 + y_0
\text{second ball has:}
y_2 = a(t-1)^2 + y_0
\text{so the distance between the two balls is:}
y1-y2 = at^2 - a(t-1)^2
= a(2t +1)
\text{so what you should say at the end is that the distance between the two balls is gradually increasing (as t is a positive variable) }
\text{also note that a = g}$

ocean sealBOT
#

Pealover

thorn vortex
#

@alpine sable

#

Sorry for the bad output

alpine sable
past thicket
#

Is it x multiplied with 2 or x to the power 2

alpine sable
alpine sable
past thicket
#

So x square is common and multuply everything else

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That is left

alpine sable
#

So the answer is x7

past thicket
#

X8

alpine sable
#

How?

#

I took LCM of them and the answer is x7

past thicket
#

U take x2 common so in first term there nothing left and in 2nd term x2 and 3rd x4 so when u multiply x2 x2 x4 = x8

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Term them into fraction

past thicket
#

x6 /x2 = x4

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x2 *x4 = x6

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Powers add when multiplied

alpine sable
#

Ok my silly mistake

glass lichen
#

what are you stuck on?

alpine sable
#

Now I am getting this answer

glass lichen
#

stem is the start of the number

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1st stem is 1

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the leaves are just the ones digits

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first line of the plot is 1 0

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yeah, cause there's only 1 10..

glass lichen
# alpine sable

since x is prime, you just need to consider the LCM of the powers themselves

glass lichen
#

you dont have any data that starts with 2, so clearly not

glass lichen
#

LCM(2,4,6) isnt 6

alpine sable
#

What does part (a) mean? I don't understand the English.

alpine sable
glass lichen
#

actually yes it's x^6

alpine sable
glass lichen
#

because you can make it smaller

#

the quick LCM is just multiply them all together

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but you then check if it can be reduced via prime factorization

alpine sable
#

Ok

glass lichen
#

ex the LCM of (2,4,6) is 12 because 2=2, 4=2^2, 6=2*3, so the LCM has to be 2^2*3

glass lichen
#

well what are the stem of them?

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yes

dire pilot
#

would i stll make the - and -8q postive here?

#

I still*

glass lichen
#

yes, -1*-1=1

dire pilot
#

even if it is in parenthesis

glass lichen
#

it's still -1*-1...

dire pilot
#

ok thanks m8

glass lichen
#

$-1\cdot -1\cdot 8q$

ocean sealBOT
dire pilot
#

so this right?

glass lichen
#

no

#

since when was -4+8=-4

dire pilot
#

oh

#

im dumb

#

thanks

glass lichen
#

looks like it

dire pilot
#

can someone help me with ths

#

this

#

nevermind

alpine sable
glass lichen
alpine sable
dire pilot
#

I already figured it out

#

thanks tho

stiff moth
#

how would i go about proving this trig identity

#

so far i have gotten til:

warped phoenix
#

Can someone help me on how to solve this?

stiff moth
muted crown
#

How do I find x here
X^5 +2x - 7 = 0

shell widget
#

Either completing the square, factorization, quadratic formula

#

@stiff moth sec^2(x) = 1 + tan^2 (x) and cosec^2 (x) = 1 + cot^2 (x)

#

Use these identities

stiff moth
shell widget
#

Start from LHS and write sec^2 (x) as 1 + tan^2 (x)

#

But for cot^2 (x), rearrange the identity cosec^2 (x) = 1 + cot^2 (x)

#

Plug in whatever u get for cot^2 (x) too

#

@warped phoenix What you basically have is $(81 x^6 y^7 )^{\frac{1}{3}}$ And recall that $(abc)^n = a^n b^n c^n$

ocean sealBOT
alpine sable
#

Hey

#

Are they equal?

final viper
#

what function satisfies f(x+y) = f(x) + f(y)

alpine sable
#

just the syntax

shell widget
#

yes

queen wigeon
#

yes, but usually its written like it is on the right side. however, rational functions with one in the numerator are written as, for example, $\int \frac{dx}{x}$

ocean sealBOT
#

mchen10

alpine sable
#

Aight! Thank you both!

alpine sable
#

A school offers three subjects: Mathematics, Art and Science. At least 80% of students study both Mathematics and Art. At least 80% of students study both Mathematics and Science. Prove that at least 80% of students who study both Art and Science, also study Mathematics.

Students can study any combination of Art, Math and Science. Draw a Venn diagram and you see that the set of students can be split into 8 different groups. Now we introduce the following variables: none is the number of students that do not attend a course. a is the number of students that only attend art, but no other course. am is the number of students that attend art and mathematics but not science. ams is the number of students that attend arts, mathematics and science. m, s, ms, as are defined in a similar way.
From the Venn diagram we see, the number of all students is none+a+m+s+am+as+ms+ams. The number of art and science students that is attending the math course is ams, the number of art and science student that is not studiing math is as. The number of students that study at least math and science is ms+ams, the number of students that is studing math and arts is am+ams. So your problem can be stated in the following way:
Given the nonengartive integer numbers none, a,m,s,am,as,ms,ams.
if
am+ams\<= (80/100)*(none+a+m+s+am+as+ms+ams)
and
ms+ams >= (80/100)*(none+a+m+s+am+as+ms+ams),
then
ams >= (80/100)*(as+ams).
ProofWe have
none+a+m+s\>=0
and so
am+ams >= (80/100)*(am+as+ms+ams)
and
ms+ams >= (80/100)*(am+as+ms+ams).
These inequalities can be transformed to
-4am+ ms+ams >= 4as
ma-4ms+ams >= 4as
If we add these two equations and divide them by 2 we get (1/2)*(am+ms)+ams >= 4as. But -(1/2)* (am+ms)>= 0 and so
ams>= 4as. Adding 4ams and dividing by 5 gives
ams >= (80/100)*(as+ams).

warped phoenix
#

Hey guys

#

what is domain and range?

#

I am learning to graph radical functions and its asking me what the domain and range is

#

how do i find it

#

from what i can tell its what x and y can be on a graph?

velvet forum
#

domain is x value

#

range is y

warped phoenix
#

so how do i find it

#

that could be any point on the graph

#

x and y

#

@velvet forum

velvet forum
#

for domain

#

visual a straight horizontal line across anypoint of the graph

#

if the horizontal line only touch the graph once then it's domain function

#

called horizontal line test

#

vertical line test for range

#

for example a parabola have 2 roots or points that a horizontal line would touch

#

therefore it's not a domain function

#

but is a range

#

basically any x value that doesn't repeat is a domain

#

and of course y is range

#

at least that's what i can remember after a year out of school

#

makes sense?

warped phoenix
#

kinda

#

what does it mean when they say the domain is all real numbers

#

@velvet forum

night token
#

who can help me with some statistics is something complicated

glass lichen
warped phoenix
#

@glass lichen how would i figure that out?

glass lichen
#

you'd look at the function

warped phoenix
#

that its all real numbers

#

oh

#

so if its a domain function

warped phoenix
glass lichen
#

no

#

domain of a function will be a subset of the real numbers

alpine sable
#

@warped phoenix The domain of a function is the set of all x-values of a function, which gives the range. (Or, the set of y-values of a function from a given set of x-values.)

For example, let's take y = 2x + 3. This function has a domain and range all consisting of real numbers. When graphed, you can visually see this is true.

Let's take y = x^2 + 2x + 5. Just by looking at it, you can use any real number as an x-value. But, the output is not infinite. When graphed, you can see it has a minimum* value. of 4 when x = -1. Thus, the domain is (-∞, ∞), but the range is [4, ∞).

There are some functions that have restrictions with their domain. For example, y = sqrt(x). We know that the square root of a negative number creates imaginary or complex numbers, so anything x-value below 0 will give an imaginary output. Thus, the domain is [0, ∞). The range is also affected by this, and thus, the range is also [0, ∞). You can see this visually by graphing it.

So, in short, the domain is the set of x-values of a function/relation, and the range is the set of y-values of a function/relation.

warped phoenix
glass lichen
#

the range isnt R

warped phoenix
#

so y is not guaranteed to a real number? @glass lichen

ionic jewel
#

i didn't read the question but I imagine he means the y is a real number, but not every real number is a possibility

#

read: a subset of reals

glass lichen
warped phoenix
#

im...still confused

glass lichen
#

ok, are you gonna ask a meaningful question or just state you're confused?

warped phoenix
#

wow

neat mesa
#

Hi, I am just starting geometry and I’m struggling to understand it and didn’t do so well on my last test. Any tips for understanding it and studying effectively???

neat mesa
sleek elbow
#

first comes understanding tho

sleek elbow
neat mesa
#

Alright thank you so much!

sleek elbow
#

also if you have trouble understanding stuff, feel free to ask here @neat mesa

arctic wren
#

So, how i can manipulate this limit to get the answer and dont fall on 0/0 ?

hazy dome
#

Actually

#

Use L’Hôpital’s

#

Yea that’s easier

arctic wren
#

@hazy dome i don't know L'Hopital's

hazy dome
arctic wren
#

It's before the book demonstrates L'Hopital's

arctic wren
hazy dome
# arctic wren Yes

Basically take the derivative of the top and bottom and reevaluate the limit

arctic wren
#

But i just saw y'=( f(h+x) - f(x) )/ h

velvet forum
#

@warped phoenix

arctic wren
neat mesa
hazy dome
arctic wren
#

Ok

#

Thankss

hazy dome
#

Don’t mind the sec stuff on the top. Just look at the limit stuff as a point of reference

hazy dome
glass lichen
#

rationalize

hazy dome
#

How? It seems very difficult and cumbersome to do

glass lichen
#

like any other rationalization.. just need to know difference of cubes and squares

hazy dome
glass lichen
#

$\frac{\sqrt[3]{x}-1}{\sqrt{x}-1}\cdot\frac{\sqrt{x}+1}{\sqrt{x}+1}\cdot\frac{\sqrt[3]{x^2}+\sqrt[3]{x}+1}{\sqrt[3]{x^2}+\sqrt[3]{x}+1}=\frac{\sqrt{x}+1}{\sqrt[3]{x^2}+\sqrt[3]{x}+1}$

hazy dome
#

Oh wow

ocean sealBOT
arctic wren
#

The second one is the difference of cubes?

hazy dome
#

At least it can be manipulated to be one

glass lichen
#

yeah the fraction w/ 3 terms is the congujate for difference of cubes

#

$(a-b)(a^2+ab+b^2)=a^3-b^3 \ a=\sqrt[3]{x} \ b=1$

arctic wren
#

I cant remeber that

hazy dome
#

Thanks for reteaching me that

ocean sealBOT
arctic wren
hazy dome
#

I prefer L’Hôpital’s in this case tho because it’s easier

glass lichen
#

eh

#

if you dont know L'H you cant use it, plus this is more elegant imo

still jasper
#

why is sin of 2x 's period 2pi divided by 2 instead of 2pi multiplied by 2? Graphically it's obvious but wanted to know if there was a formula or something to reach this result

arctic wren
#

Period= 2π/k , i think

#

Sin(kx)

still jasper
#

oh I see

#

I was doing the rule of 3

#

but they were Inversely proportional

alpine sable
#

|15 - 51| - |150 - 510| - q = 100

#

$|15 - 51| - |150 - 510| - q = 100

gilded nova
#

hello

#

I have to clear the variable x from the function

#

so that i'm left with something like x=...y...

tawny condor
#

what do u mean

#

isolate x?

#

thats..

#

uh

#

what

dull onyx
#

r u trying to find the solutions or something

gilded nova
#

So for example if I have something like y=x+2

#

I need x=y-2

tawny condor
#

ohno he wants to isolate x

dull onyx
#

?!

#

oh

tawny condor
gilded nova
#

sorry english isn't my main language

tawny condor
#

LEMME GRAB MY CUBIC FORMULA REAL QUICK

#

@gilded novar u trying to find the inverse maybe

gilded nova
#

not the inverse

tawny condor
#

welp

#

-x^3 + 3x^2 + x - (y + 3) = 0

gilded nova
#

I'm trying to solve a solid of revolution exercise

#

I'm given that function

#

And it rotates around x=0

tawny condor
#

wth

gilded nova
#

in the (0,1) interval

dull onyx
#

i have no clue what ur trynna do

#

sorry!

gilded nova
#

In mathematics, engineering, and manufacturing, a solid of revolution is a solid figure obtained by rotating a plane curve around some straight line (the axis of revolution) that lies on the same plane.
Assuming that the curve does not cross the axis, the solid's volume is equal to the length of the circle described by the figure's centroid mult...

tawny condor
#

here u go

#

replace a with y

#

and u got ur x

gilded nova
#

omfg

#

I guess i'm skipping it

alpine sable
#

Hey guys, having a bit of trouble with this problem:

Find the equation of the tanget line to y = x^3 - 3x at x = 2.
Watching a video on it and I don't understand this one step.

#

Wouldn't it be (2 + h)^3 - 3(2 + h)? where did they get the end part from?

tawny condor
#

why are you using limits?

#

Are you allowed to differentiate normally?

#

if not,

#

then

#

the (2 + h)^3 - 3(2 + h) is like x^3 - 3x but u put in 2+h instead of x

#

thats f(2+h)

#

then they subtract f(2), which is 2^3 - 3 * 2

alpine sable
#

oh so its for the entire thing! got it, thanks

alpine sable
#

@alpine sable by definition, $f'(x_0) = lim_{h \to 0} \frac{f(x_0+h )-f(x_0)}{h}$

ocean sealBOT
#

magnos

alpine sable
#

thanks guys, much appreciated

#

thats where the 2nd part comes from

tawny condor
#

np

alpine sable
harsh acorn
#

Simplify the expression, leaving your answer in its factorised form. 2(2x – y)² – 6x(2x – y)

#

can someone tell me how I can work this out?

arctic wren
#

Whats is the derivative of this function? The answer on my book is (e^x)(3x²+x-5) but my result is (e^x)(3x²+11x+5)

glass lichen
#

$f'(x)=e^x(6x+5)+(3x^2+5x)e^x$

ocean sealBOT
glass lichen
#

your answer is correct.

arctic wren
#

Thanks

keen surge
#

how do i solve this?
105 = 25m + 9c + 16s

sleek elbow
keen surge
#

ok, so in order to solve for all 3, i need to solve 3 times?

sleek elbow
#

Im not sure you can

keen surge
#

?

sleek elbow
#

like

#

wait

#

are m and s units

#

or variables

keen surge
#

just variables

#

could be x,y,z or a,b,c doesnt matter

sleek elbow
#

I dont think you can solve an equation with 3 variables 🤔

#

not sure tho

keen surge
#

mm, lemme give a word problem, this was my attempt in coming up with an equation to solve

sleek elbow
keen surge
#

was hoping it would help, but if not nw ill bounce

sleek elbow
noble sinew
#

What? 3380000 is what? And where does 105000000 come from? (It isn’t 3380000 * 5 * 6)

#

And right below you say they make another amount

keen surge
#

yes, thats where the 105 comes from

noble sinew
#

They aren’t equal

#

,calc 338000065

ocean sealBOT
#

Result:

1.014e+8
noble sinew
#

Notice that isn’t your number

keen surge
noble sinew
noble sinew
keen surge
#

platinum is being converted into the other number

noble sinew
#

Instead post original question wording instead of this

keen surge
#

lets call the other number N

#

25N = 80 platinum

keen surge
#

ah nw, i think since i wrote out the word problem myself i can probably solve now

#

thanks for the help!

#

idk how to close the channel if thats a thing here

noble sinew
#

The other thing still applies

keen surge
#

?

noble sinew
#

,w 338000065

noble sinew
#

Notice that isn’t 105,000,000

keen surge
#

o right, 😕 mb

#

this isnt in a book or anything, its a real world problem

#

but ye, ill just calc for the hour

#

instead of trying to calc for the whole thing at once

#

thanks 😄

#

mm, i lie, my math isnt good enough

#

18,200,000 = 25m + 9c = 16s

finding the lcd and solving for m [3600 is the lcd for 25, 9 and 16, and multiplying by 144 got me the next line], m, c and s being arbitrary

2,620,800,000 = 3600m + 153c + 2304s

past minnow
#

Piper Nakamura Mawji

glass lichen
past minnow
#

Did you get the job

glass lichen
#

again, only use the help channels if you have a math/math-related question

past minnow
#

Did you?

glass lichen
#

If you are not going to follow the rules of the server, then stop typing.

past minnow
#

My guy did you or did you not

#

Who’s dick are you trying to suck

glass lichen
#

Again, this is a help channel either use it properly or leave

quaint trout
#

<@&268886789983436800> stareflushed

#

Only has 5 messages, obvious troll is obvious

glass lichen
#

Yeah this

past minnow
#

NOOOOO PLEASE DONT BAN ME!

#

😡

glass lichen
#

And can confirm they should be banned in ModMail / dms

past minnow
#

OH GOD NO

#

I AM GOING TO BE BANNED FROM THE MATHEMATICS DISCORD SERVER?!

#

WHAT WILL I DO

#

MY WORLD IS ENDING

quaint trout
#

Hopefully look at yourself and the mirror and reflect on what your life is

past minnow
#

MY LIFE IS NOTHING WITHOUT THE MATHEMATICS DISCORD SERVER

#

PLEASE DONT BAN ME!

#

I WANT TO ROLEPLAY ON MINECRAFT WITH MOSH

candid torrent
#

why'd you guys ban them

#

they seems like a cool guy

#

👍

glass lichen
candid torrent
#

...

#

it was sarcasm I know why they got banned and I don't really care

glass lichen
#

k

rocky cape
#

Can someone help me with a ii) ?

mossy lion
#

we cant do it for you

#

do you mean you need help doing it or are you just looking for a calculator

candid torrent
#

yeah...

#

it's so strange

#

fanks

#

ok you

mossy lion
#

lmfao wtf. just read the conversation

candid torrent
#

don't need to criticize them that much

#

it's just weird that's all

warped phoenix
#

Can someone help me out with derivatives

#

wtf

candid torrent
#

send

mossy lion
#

alright is this a hw question?

warped phoenix
mossy lion
#

alright do you have your notes on polynomial long division? the textbook can help too

candid torrent
warped phoenix
#

1 is free i think

mossy lion
warped phoenix
#

ofc! ❤️

glass lichen
#

<@&268886789983436800> same person as Gombo

tall wing
#

how do we know this is gombo again?

#

i mean i guess

#

"don't ban me again"

#

is obvious

#

but

glass lichen
#

they're saying the exact same stuff

tall wing
#

oh

#

alright mosh

#

banned

violet hemlock
#

Ty

random talon
#

How would you prove the following limit? $lim_{m,n\rightarrow\infty}\frac{(-1)^n}{(-2)^m}=0$

ocean sealBOT
#

econguy

glacial hedge
#

because they both approach infinity

#

or wait

#

u mean like formal proof?

random talon
#

Formal proof. Epsilon style proof

glacial hedge
#

😦

glass lichen
#

F

glacial hedge
#

uno seconda

glass lichen
#

that's an F

glacial hedge
#

yo thats lame who would make u do that

#

for

#

epsilon > 0 and delta >0

#

$ 0 < \sqrt {(x-a)^2+(y-b)^2} < delta$

#

uh

#

$0 < \sqrt {(x-a)^2+(y-b)^2} < delta$

ocean sealBOT
#

Elonmosqito96

glass lichen
#

\delta

slow monolith
#

have a question

#

can yall help?

#

i need a run diwn on how to solve this and simplify

mossy lion
#

?

glacial hedge
#

then:
$|(-1)^n/(-2)^m-0|<\epsilon$

ocean sealBOT
#

Elonmosqito96

slow monolith
#

run down

sterile escarp
#

Please help me

glacial hedge
#

dafuq people stop spamming

slow monolith
#

pls i just need help man

mossy lion
#

jesus this is a mess

#
  1. Before asking a question, make sure that the channel you are using is not currently in use. An occupied channel would generally have an ongoing discussion or a trailing unanswered question. Likewise, when you are done using a channel, make this clear so that it's open for others to use.
#

afaik @zinc oar was here first but idk if they actually want to go through their problem or not

solar tapir
#

Is this channel available?

slow monolith
#

can somone help me in channel one

mossy lion
glacial hedge
solar tapir
#

Sorry, will go to another

random talon
glacial hedge
#

im not very fluent with epsioln delta proofs in multi var case

#

😩

random talon
#

Haha neither am I. It’s kinda crazy. Otherwise any other kind of approach, I guess I can work with that

#

I used Matlab to kinda check if this was true, but that’s it

glacial hedge
#

were u not paying attention.....

#

this channel is sorta being used...

#

he asked way before u

glacial hedge
#

$0 < \sqrt {(x-a)^2 +(y-b)^2} < \delta$

ocean sealBOT
#

Elonmosqito96

mossy lion
#

yeah that looks great

glacial hedge
#

no thats wrong

#

it doesnt satisfy remainder theorem

mossy lion
random talon
#

Thanks man, at least I don't feel dumb for not knowing how to do it @glacial hedge . Good to hear a second opinion

glacial hedge
#

oh wait nvm

#

hehe

mossy lion
#

ye that was the result

glacial hedge
#

my bad

#

xD

mossy lion
#

youre good

glacial hedge
#

i thought that was what he was dividing

jagged pendant
#

what should i use for latex code inside of html for ease?

glacial hedge
#

um

jagged pendant
#

is there not a good browser extension or something?

glacial hedge
#

probably mathjax

jagged pendant
#

seems a lot of junk software out there

glacial hedge
#

mathjax is pretty well trusted and pretty good too

jagged pendant
#

i forgot i had that already lol

glacial hedge
#

not sure what that means but ok xD

strong citrus
#

Twenty bored students take turns walking down a hall that con-
tains a row of closed lockers, numbered 1 to 20. The first student opens all the
lockers; the second student closes all the lockers numbered 2, 4, 6, 8, 10, 12, 14,
16, 18, 20; the third student operates on the lockers numbered 3, 6, 9, 12, 15, 18:
if a locker was closed, he opens it, and if a locker was open, he closes it; and so
on. For the ith student, he works on the lockers numbered by multiples of i: if a
locker was closed, he opens it, and if a locker was open, he closes it. What is the
number of the lockers that remain open after all the students finish their walks?

slow monolith
#

(x*x^(-2)y^((5)/(3)))^(2)

#

need help with this

alpine sable
glass lichen
obsidian juniper
glass lichen
#

so to get the tangent you make the points get closer and closer

alpine sable
glass lichen
#

yes, h is the run

alpine sable
glass lichen
#

yes

glacial hedge
#

I just had a flash of brilliance

#

the abs in the proof

#

removes the -'s

#

so

#

(-1)^n

#

doesn't affect the thing

#

so its really

#

1/2^m

#

which can be proven using single var stuff

random talon
#

Well, but holding m=1 and allowing n to vary we would have something (1/2 -1/2 1/2 -1/2...) so it diverges

#

But my apologies, what I want to prove is $\lim_{m,n\to\infty}\frac{(-2)^n}{(-3)^m}=0$

ocean sealBOT
#

econguy

alpine sable
#

@glass lichen what does it mean when youre given a function and not 2 points? youre still trying to find the slope of the tangent line (the tangent line in this case is f(x) = 1/x right?), just without the 2 points?

glass lichen
#

You have 2 points

#

(x,f(x)) and (x+h,f(x+h))

#

those are always the 2 points, which you can get by reading first principles

alpine sable
#

oh, it all clicked now. thanks

full wasp
#

are all countably infinite sets numerically equivalent??

mossy lion
tired hamlet
#

How would I start this one?

marble comet
#

P = principal amount

#

(20,000)

#

e I believe refers to Euler's natural number

#

r = rate which we have to find

#

A = 43,957.90

#

t = 15 years

tired hamlet
#

I got 43957.90=20000(2.718)^r(15) I’d that right

#

*is

marble comet
#

yeah

#

are u allowed to use a calculator?

tired hamlet
#

Yeah

marble comet
#

aight then rearrange the equation in terms of r

tired hamlet
#

How would I do that?

marble comet
#

here lemme try doing it

#

@tired hamlet have u done logarithms yet?

tired hamlet
#

Yeah

marble comet
#

great

#

so once u divide A/P

#

u get around 2.198 = e^(15r)

#

now take the log base e of each side

#

on the right side, according to the inverse property of logarithms u get 15r

#

and on the left side u get log base e of 2.198

#

so log _ e (2.198) = 15r

#

on a calculator, u input (log 2.198)/(log e)

#

u get .787547 so on

#

divide that by 15

#

and u get .0525 around

#

so 5.25 percent is the answer

tired hamlet
#

Thx so much

marble comet
#

np

#

: )

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on a calc it's ez, but without it it's hard

acoustic bay
#

Can someone who knows R help me find the correlation values for my data set?

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I have over 90 columns, I want to test the correlation between all of these variables against one other variable which is already contained in the 90.

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This is what I have so far

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for(col in 1:ncol(longitudinalbl)){
myCortest = cor.test((longitudinalbl)[col], IDE.BL$SSI_worst, na.action=TRUE, method = "sp")
myCortest$estimate
}

ocean sealBOT
#

kevinFDG

alpine sable
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Can someone give me a good math problem? (Of any topic)

acoustic bay
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Can you try the problem I just posted above

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<@&286206848099549185>

sullen karma
#

?

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What msg

acoustic bay
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the one above, i was asking about how I can find the correlation values in R for my dataset. i posted the code I have so far above

rich basin
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I was wondering why is my answer not correct

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$\frac{2}{2^{8}-2}$

ocean sealBOT
#

Travelling Salesman

acoustic bay
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@rich basin you have to ask in a channel where someone hasnt asked a question, I just posted above.

rich basin
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This is what I have right now

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sorrry

acoustic bay
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Your good, I dont think anyones gonna answer mine anyway so you can have it actually.

rich basin
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Thanks

tough hedge
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where can i post my question?

rich basin
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You can post on question 1

tough hedge
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okay thanks!

rich basin
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<@&286206848099549185>

indigo storm
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What's the answer?

hasty narwhal
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yup. take the lcm and add, and use a^2-b^2=(a+b)(a-b)

rich basin
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Sorry, but I already post a question

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Too much noise covering up my original question

hasty narwhal
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I'm sorry. I didn't realise

rich basin
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Please delete

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,w solve (8 choose 4) / (2^8-2)

ocean sealBOT
rich basin
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,w solve 81/127

ocean sealBOT
rich basin
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,w solve (8 choose 4) / ((2^8)/2-2)

ocean sealBOT
coral pagoda
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Why the -2?

rich basin
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,w solve ((10 permutate 6) + (10 permutate 5) + (10 permutate4) + (10 permutate 3) + (10 permutate 2) + (10 permutate 1))/ (15 permutate 6)

rich basin
ocean sealBOT