#help-23

1 messages · Page 380 of 1

opal fractal
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of course, it will give different areas for different functions

quasi bison
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AI slop video

oak cobalt
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Ooh, alright. Thanks.

#

.close

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marsh wraith
#

h : S→Nx{f} ∪ Nx{g} with S to ( f(i),f) and with T to ( g(i),g) how to prove h is bijection right here

peak estuary
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what are f,g,S,T?

marsh wraith
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In the context of this question

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I mean right here h is not bijection

peak estuary
#

yes that certainly doesnt work

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and is also not what you wrote

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consider finding h:SuT -> Z

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and I hope S and T are disjoint, otherwise you have to do some extra bookkeeping

safe radishBOT
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@marsh wraith Has your question been resolved?

safe radishBOT
#

@marsh wraith Has your question been resolved?

warm warren
flat frigateBOT
#

Annie Maqionde

marsh wraith
warm warren
flat frigateBOT
#

Annie Maqionde

warm warren
#

And eitherways, no function can possibly map a single preimage to two different images.

safe radishBOT
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@marsh wraith Has your question been resolved?

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low jolt
#

.open

vale cypress
#

hi, i want to know how to sketch the argand diagram from arguments?
I always keep on getting it wrong, and Im getting really frustrated

vale cypress
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hi, would it be possible to get some help

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im really stuck :/

marsh wraith
vale cypress
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not rlly ://

marsh wraith
vale cypress
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sure

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hi...

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so

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can i get some help?

split kayak
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How far in the problem you are?

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@vale cypress

vale cypress
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uhh

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i have no clue how to do part b

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like 0 idea whatsoever

split kayak
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Argand basically is just a plot over the Complex Plane

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Now, you have to regions and have to find their intersection

vale cypress
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i get that

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just dk how to do so

split kayak
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Starting from the first set.

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Would you know how |z| <= 1 would look like?

vale cypress
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uhh

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a circle of 0,0 centre

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and 1 radius?

split kayak
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yea

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Now, do you agree that |z - (0+0i)| <= 1 is just the same?
And if so, what do you think happens when you have |z - (1+0i)| <= 1

vale cypress
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uhh

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centre 1,0?

split kayak
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yep.

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Its a shift

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then, |z - (0+1i)| <= 1 ?

vale cypress
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0,-1 radii

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i think i get this now

split kayak
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almost

vale cypress
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*0,-1 centre , 1 radii

split kayak
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nope

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The center is off

vale cypress
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oh wait mb ://

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0,1 cetnre

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centre

split kayak
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Well, |z-z_1| <= is just a circle shifted to have its center on z_1

vale cypress
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uh-huh, i think i get it now

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but what about arg(z-z1) ?

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wait

split kayak
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Remember that
a+bi is the analog to (x,y)
and re^arg(z)i is analog to (r,theta).

vale cypress
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is it just a line of -1 slope that passes thru z1?

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oh wait what? then what should it look like ://

split kayak
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Its a sort of "pizza slice" of the whole domain

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I suppose you had trig at some point already

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If i tell you
0 < theta < pi

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You should know thats the upperhalf of the (x,y) plane

vale cypress
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yeah

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so its basically 3/4's of the top half?

split kayak
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not quite sadly

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You have to consider that the argument is shifted by z_1 being in there.

vale cypress
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and then deduct by z1?

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so like shift to the left by z1?

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*right

split kayak
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sort of, yep.

vale cypress
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but then how would you draw that out

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thats the most confusing part where i don't get

split kayak
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you can think that (z-z1) makes the new center of the plane be z1

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If so, try to find how 0 < arg(z) <3pi/4 would look like and then shift accordinglt

vale cypress
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Ohhhh

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so basically

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its like this slanted line to z1

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then

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flat?

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cuz the argument starts on positive x-axis. and with z1 being the origin, it just goes flat after reaching it?

split kayak
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Yep.

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And then find the intersection

vale cypress
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ahh

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gotcha

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just a quick lil second question

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for this question

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do i just solve for the sector area then - C1's area under curve between P and 0?

split kayak
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prob theres a better method but i cant think of it rn

vale cypress
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and better question

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is the area under C1 curve the area between OP and the intersection between C1 and the initial line

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cuz I'm kinda confused with that part a lil, don't really get which area is the area under curve

safe radishBOT
#

@vale cypress Has your question been resolved?

safe radishBOT
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spark lynx
#

My mean is 106.31, which is accurate

52.83
66.51
75.43
78.1
82.18
83
85.09
86.48
89.04
89.24
90.29
90.29
90.4
96.41
98.62
98.73
100.34
103.37
105.45
107.95
109.18
117.06
117.8
120.77
122.49
124.6
124.8
130.47
131.49
133.18
133.36
137.72
140.92
141.22
166.19

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Why is my standard deviation calculation so absurdly off

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It should be around 24-30

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I think intuitively

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oh wait lmao nvm this is because thats variance

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I'm stupid I need to still calculate standard deviation

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.close

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ocean vine
#

(3)6 plz help

safe radishBOT
normal moss
ocean vine
#

thats what i need help with

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idk

normal moss
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!xy

safe radishBOT
#

Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.

ocean vine
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3x6 is the problem

normal moss
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Otherwise I assume it's 3*6

ocean vine
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it is

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so any help>

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??

plucky elk
ocean vine
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my teacher said i couldnt

plucky elk
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oh what grade does your teacher teach?

ocean vine
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5th

normal moss
plucky elk
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oh 5th grade, are you 11 years old?

ocean vine
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...

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noo

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i 18

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im

mint plume
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try adding 6 3 times

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6+6+6

ocean vine
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6

normal moss
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I really don't see the appeal in doing this

ocean vine
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12

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118

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765432;''

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`u71u89qwijoskldmc

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jn2qeiwk;ldsmv;z

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18

mint plume
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almost there

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yes 18!

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think of multiplying as adding multiple times

ocean vine
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now can yoou teach me dirivtive algebra eginomics?

plucky elk
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<@&268886789983436800> troll

ocean vine
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sorry

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plz

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i leave

normal moss
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thanks

vivid stream
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@ocean vine Just so we've made it clear: do not shitpost in help channels please. If you want to shitpost, go to #chill

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I'm closing this channel now.

#

.close

safe radishBOT
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storm rock
safe radishBOT
storm rock
#

Could someone help me figure this out

safe radishBOT
#

@storm rock Has your question been resolved?

flat frigateBOT
safe radishBOT
#

@storm rock Has your question been resolved?

upper kraken
#

And since you want to integrate y=r^2+1 for 0< r < 1 for a rotating point, by the polar change of variable, you get the integral for theta from 0 to 2pi of the integral for r from 0 to 1 of (r^2+1)r dr dtheta

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rich jay
#

I don't understand why he added 45 under 45 and 0 with 45 below it, this is "Solving quadratic equations using square roots" and he said this is a "way" to do it, does that mean I can still do it the regular way? Which is having the first number of the equation be the fraction of A and B? while ignoring C (equals 0)?

rich jay
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Sorry if my explanation is overcomplicated, I'm not very good with english math so...

austere goblet
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this way works and is quite faster iff b = 0 (that is, you don't have a bx term)

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of course, all of your regular tricks like quadratic formula still work

rich jay
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what is a bx term??

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nvm I searched it up

rich jay
austere goblet
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because doing it this way is the fastest given the conditions

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also, the question explicitly wanted the person to sqrt both sides

severe pond
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its just isolating the variable term

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your "way" of doing this isn't really a "way" at all

austere goblet
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oh hi knief

rich jay
severe pond
#

its just using the conclusion of the actual method used here from your memorization

severe pond
rich jay
#

I'm gonna close this now

#

.close

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ancient onyx
#

help

safe radishBOT
ancient onyx
#

i dont understand lim approaching infinity at all

hollow dock
#

Which part of it

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The concept or the actual derivation?

burnt mantle
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try splitting the denominator and notice how cosx is bounded

ancient onyx
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both

severe pond
ancient onyx
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yes

severe pond
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so lim x-> inf is just asking for the limiting behavior of the function as x gets arbitrarily large

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does the function blow up to infinity or does it approach some finite value or does the function have no limiting behavior because it oscillates or something

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,w plot e^(-x)

severe pond
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here we say lim x-> inf e^(-x) = 0 because regardless of how close to 0 you want the function to be, we can always find some point after which the function is within that distance from 0

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and by "find some point after which" i mean there is some x value so that for all x values to the right of it...

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in the usual limit we speak of x values within some distance from say a for lim x -> a. for lim x-> inf we consider all of the x values to the right of whatever point at which the function satisfies the desired inequality |f(x) - L| < eps

safe radishBOT
#

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covert sphinx
#

could i get help with these questions?

safe radishBOT
#

@covert sphinx Has your question been resolved?

covert sphinx
spice canyon
#

all?

covert sphinx
#

yah 😓

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im working on 17 so i guess I’d like help with #18 first

spice canyon
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then

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They're saying that the amount of volume between the volume of cylinder and cube is equal to 1717. Aka. They filled the difference of the two volumes with water amd it ca,e out to be 1717

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so first let's calculate the area then we will go on from there.

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volume*

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volume of the box = 20×20×20 = 8000
Volume of cylinder = (pi)r²h . h is 20 and r is diameter/2 which is 10, so.
10²×20×pi = 2000pi.

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Now. 8000-2000pi is the difference in volume

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And what else was the difference in volume?

spice canyon
covert sphinx
#

so the difference is 6000 cm3?

spice canyon
# covert sphinx could i get help with these questions?

For 19. The upper part seems a bit tricky, I'm sure you can find the volume,e of the cuboid with the lengths of 30×8×6.
For the upper curved part. You see that the entire thing has a length of 20. Height of 10 width of 8cm (it shaes the same with as the other figure) but. There's a big portion cut from the middle of it , it's also given to be in the shape of a semicircle. Since it's a semicircle in 2d If you add a width to a semi circle then it becomes half of the part of a cylinder similar to how extending a circle and giving it height makes it a cylinder

spice canyon
spice canyon
covert sphinx
#

how do i do that? catthink

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like find pi

spice canyon
#

And didn't the question say that they filled the remaining space of the cube with a water of volume 1717?

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What is the remaining space equal to?

covert sphinx
#

1717 cm3?

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1 ml = 1 cm3

spice canyon
covert sphinx
spice canyon
#

So now

covert sphinx
#

i get it now

spice canyon
#

Nice

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Now you treat pi like a variable. Then calculate for pi

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Upto four digits the question says

spice canyon
covert sphinx
#

so like

spice canyon
covert sphinx
#

ahhhh

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👍

spice canyon
#

How would you say that 3.1415926 = 22/7

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😭

#

Also I'm sure that there are like a billon approximations for pi.

covert sphinx
#

yeah

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i think a) 3.142

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wait but how do i get 3 significant figures

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@spice canyon got 1783 cm3 for 19

spice canyon
#

arent you supposed to calculate pi

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😭

covert sphinx
#

ya that’s for q 18

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i was waiting for u to get back so i did 19

covert sphinx
cerulean berry
#

3.14 is 3 sf

covert sphinx
cerulean berry
#

no idea

covert sphinx
#

im crine

cerulean berry
#

they just wanted to see ur rounding skills

safe radishBOT
#

@covert sphinx Has your question been resolved?

safe radishBOT
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wise cloud
#

Why is distance formula usually written as 2-1 like x2-x1 but not x1-x2 while the answer is the same

wise cloud
#

or there is no explanation for that

naive dragon
#

Not really important tho

wise cloud
#

Okay ty

#

.close

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shut barn
#

I am trying to do 3.1.1

I don't really understand how to plot bifurcation diagrams in general and I am not even sure about my vector fields as well.

As for my work,

I have used the quadratic formula from high school to find that we have $r^2 - 4 = 0 \text{ or } |r| \geq 2$

To find where the saddle note happens, I need to look at where $f(x, r) = 0$, differentiating it with respect to $x$ I get $f_x = r + 2x$

With this I identified the 5 different scenarios

  1. 2 fixed points if $r > 2$ or $r < 2$, (stable -> unstable)
  2. 1 fixed point at $x = -1$ or $x = 1$ and $r = 2$ (half stable)
  3. No fixed points at $ - 2 < r < 2$

So I might have an idea of how to sketch vector fields for different r, but I really don't know how to sketch the bifurcation diagram. How do I do it? Where do I start?

flat frigateBOT
#

Kazuchin

safe radishBOT
#

@shut barn Has your question been resolved?

safe radishBOT
#

@shut barn Has your question been resolved?

safe radishBOT
#

@shut barn Has your question been resolved?

wild cape
#

@shut barn to get the bifurcation diagram we plot f(x,r)=0 where r is the horizontal axis and x is the vertical. in this case we can get an easy plot by solving r=...

safe radishBOT
#

@shut barn Has your question been resolved?

shut barn
#

Thank you!

safe radishBOT
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fleet valve
#

This is such a small thing that’s stumping me, I broke down the equation. Typically when it comes down to solving a radical like this it’s only one numbers.

Like if it was only -5 to the square root of 25 it’d -25

If it was 20 (the product of 25-5) it’s be 100.

But that’s not the answer. Could I get explained how to do this with a practice problem?

fleet valve
#

I also just don’t think I understand how to solve for radicals, as that is the radical sign I believe. When solving for radicals I’m Square rooting the number on the outside right..? Hence why 5 is the square root of 25

quasi bison
flat frigateBOT
quasi bison
#

but also the "outside number" is not the "answer" to the "square root".

#

it is simply a number you multiply to the result of the rooting operation.

#

for example, $6 \sqrt{16}$ isn't the statement ``the square root of 16 is 6'', and in fact it isn't any sort of statement at all;

rather it is an instruction saying: \ ``take the square root of 16, then multiply 6 with the result.''

flat frigateBOT
quasi bison
#

but for clarity's sake.

#

$25 - 5 \sqrt{25}$ means $25 - (5 \times (\sqrt{25}))$.

flat frigateBOT
quasi bison
#

though a pair of brackets wrapped around a root isn't really necessary. because the root symbol (in proper handwriting) covers all of the stuff inside of the root, it acts as its own bracket.

fleet valve
#

I’m reading this, don’t take my silence as absence. I’m just writing notes

split kayak
fleet valve
#

I do have a question, why is “5” being put in parentheses and not “-5”?

quasi bison
#

if it makes a difference for you, i can write it as:

#

$25+\paren{(-5)×\sqrt{25}}$

flat frigateBOT
quasi bison
#

same shit though

fleet valve
#

Oh and I can see how that’d simplify into 25-(5 sqrt 25

#

Okay

#

OKAY!

#

No further questions thank you so much

#

.done

#

.close

safe radishBOT
#
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covert rain
#

Why is the maximum probability 1, why can't it be 5?

upbeat swan
#

by definition

#

probability means

#

how much out of 100%

#

so

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how much from 1

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so naturally 1 is the highest you can go

#

probability 5 would mean

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500%

covert rain
#

But why is the sample space a subset of ?

upbeat swan
#

what?

covert rain
#

Omega

#

Champion space

upbeat swan
#

It’s not that the sample space is a subset of something else

#

It’s that every event is a subset of the sample space

covert rain
#

But the sample space Is a subset of the sample space ?

upbeat swan
#

yes

#

every set is a subset of itself

covert rain
#

But then what changes between a subset that has the same elements as the set and the set?

upbeat swan
#

its the same exact set then

covert rain
#

So why is it a subset?

upbeat swan
#

subset can also mean equal to the set

quasi bison
#

the symbol is even ⊆ as a visual reminder of that

#

but also you want to be able to speak of events that are guaranteed to happen

#

bc that is what Ω means as an event

covert rain
#

Why is it needed =?

quasi bison
#

but also you want to be able to speak of events that are guaranteed to happen

upbeat swan
covert rain
#

Why?

#

Why i Need to account for this case

upbeat swan
#

why what

#

so you do understand that a set contains itself

quasi bison
#

do you want to see exactly where and how it blows up in your face? or no

upbeat swan
#

why do we use ≤

#

and not < all the time

quasi bison
#

ok let's consider a very basic kind of probability space

#

rolling a dice

#

nothing fancy just standard shit

#

EXCEPT we disallow Ω as an event.

#

i.e. for us any proper subset of {1,2,3,4,5,6} will be considered an event, but {1,2,3,4,5,6} is not.

#

do you follow so far, yes or no.

covert rain
#

Yes

quasi bison
#

ok

#

now, what you'd want is that if A and B are events, then A ∪ B should also be an event, right?

#

after all, it's just those two events with a logical or between them.

covert rain
#

By what property is AUB an event again?

quasi bison
#

it's literally an axiom of probability spaces.

#

(if you reject this also then i have nothing else to say to you. as in that case you're definitely rejecting too much to be doing anything resembling probability theory)

covert rain
#

I have seen that given n events with union operations/other operations other events can be constructed, but this does not say if they are always so.

quasi bison
#

unless stated otherwise, it is implied to always be so.

#

rejecting that means dealing with edge cases and weirdness and having to bloat every single statement with "as long as it isn't the entire space" or whatever.

desert juniper
#

wait, hold up. Why is omega not allowed as an event? isnt it the sure event with probability 1?

upbeat swan
#

by definition

covert rain
#

But then isn't it enough to say event=subset?

upbeat swan
#

no

#

an event is always a subset of the sample space, but not every subset has to be an event.

covert rain
#

Example?

#

But what if for example A event -> notA event?

quasi bison
#

but then we stopped at him calling into question why the union of events was an event.

covert rain
#

I fixed

quasi bison
covert rain
#

I don't understand now why it's not enough to say that event=subset

upbeat swan
#

for example

#

Ω={1,2,3,4}
and
F={∅, Ω, {1,2}, {3,4}} (the event set)

now we look at the subset {1}. It is a subset of Ω, but {1}∈/F. So {1} is not an event in this probability space.

quasi bison
covert rain
upbeat swan
#

yes

#

but you dont HAVE to choose the event set to be the power set

covert rain
#

I mean 1 could be an event

#

I know you can only take certain items

upbeat swan
#

it could

#

if it were in F

covert rain
#

Even number type

#

But I don't mean that thing

upbeat swan
#

if omega is finite then you CAN take all subsets as events. You dont HAVE TO take all subsets as events

covert rain
#

Yes

#

I meant if they could all be taken

upbeat swan
#

yes

gray mulch
#

Consider this - if you have a box of 5 balls, 3 blue and 2 red, the probability of pulling out a blue is 3/5, a red is 2/5. You can't pull out 25 balls if there are only 5

#

Thus the probability as defined wouldn't make sense

#

If you are guaranteed to pull out a red or a blue ball, the probability is 5/5 = 1 < 5

#

So you are not guaranteed

#

Which is a contradiction

#

Again, only in this system of axioms

#

Which are called Kolmogorov's axioms.
One can invent a new set of axioms where this would make sense, but it just makes the math unnecessarily complicated

safe radishBOT
#

@covert rain Has your question been resolved?

covert rain
#

.close

safe radishBOT
#
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safe radishBOT
#
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earnest mirage
#

Hello, could someone check if this proof looks good please?

\begin{Theorem}
Assume $A$, $B$ and $C$ are sets.
If $A \cup B = A \cup C$ and $A \cap B = A \cap C$, then $B = C$.
\end{Theorem}

\begin{proof}
Let $A$, $B$ and $C$ be sets.
Either $A = \emptyset$ or $A \neq \emptyset$.
Suppose $A = \emptyset$.
In which case $A \cap B = A \cap C = \emptyset$ holds.
Also, $A \cup B = B$ and $A \cup C = C$, and because $A \cup B = A \cup C$, we have that $B = C$.\

Now, suppose $A \neq \emptyset$.
If $B$ and $C$ are both empty, then $B = C = \emptyset$, which is what we wanted to prove.
Suppose now that one of $B$ or $C$ is empty and the other non-empty, or both non-empty.
Without loss of generality, suppose $B = \emptyset$ and $C \neq \emptyset$.
Then $A \cup B = A$.
And since $A \cup B = A \cup C$, we have that $A = A \cup C$.
On the other hand, $A\cap B = \emptyset = A \cap C$.
Because $A$ is non-empty, $A = A \cup C$, and $A \cap C = \emptyset$, it must mean that that $C = \emptyset$.
Thus, $B=C$.\

Lastly, suppose $B \neq \emptyset$ and $C \neq \emptyset$.
Let $x \in B$.
Now, either $x \in A$ or $x \notin A$.
If $x \in A$, then $x \in A \cap B$.
Since $A \cap B = A \cap C$, then $x \in A \cap C$, which means that $x \in C$.
Since $x$ was chose arbitrarily, it holds for any $x \in B$.
Therefore, $x \in B$ implies $x \in C$, , so, by the definition of the subset, $B \subseteq C$.
On the other hand, suppose $x \notin A$.
Then $A \cup B$ holds because $x \in B$.
And since $A \cup B = A \cup C$, and $x \notin A$, it must be that $x \in C$.
In either case, $x \in B$ implies $x \in C$, so, by the definition of the subset, $B \subseteq C$.
The rest follow from a similar case with $x \in C$, and with that we have that $C \subseteq B$.
We shown that $B \subseteq C$ and $C \subseteq B$, thus $B = C$.
Therefore, in any case, if $A \cup B = A \cup C$ and $A \cap B = A \cap C$, then $B = C$.
\end{proof}

flat frigateBOT
#

Mor Bras

earnest mirage
#

\begin{Definition}[Subset of a set]
Suppose $A$ and $B$ are sets. If every element in $A$ is also an element of $B$, then $A$ is a \emph{subset} of $B$, which is denoted $A \subseteq B$.
\end{Definition}

\begin{Definition}[Union of sets]
The \emph{union} of sets $A$ and $B$ is the set $A \cup B = { x : x \in A \text{ or } x \in B}$.
\end{Definition}

\begin{Definition}[Intersection of sets]
The \emph{intersection} of sets $A$ and $B$ is the set $A \cap B = { x : x \in A \text{ and } x \in B}$.
\end{Definition}

flat frigateBOT
#

Mor Bras

tardy mango
#

This is unnecessarily long because of your casework

earnest mirage
#

For sure

tardy mango
#

Let $x \in B$.
\begin{itemize}
\item If $x \in A$, then $x \in A \cap B$. Since $A \cap B=A \cap C$, we have that $x \in A \cap C$, and so $x \in C$.
\item If $x \notin A$, we still have that $x \in A \cup B$ since $x \in B$. Since $A \cup B=A \cup C$, it follows that $x \in A \cup C$. But because $x \notin A$, it follows that $x \in C$.
\end{itemize}
In both cases, $x \in C$. So, $B \subseteq C$. But by symmetry, we can show that $C \subseteq B$, which allows us to conclude that $B=C$.

flat frigateBOT
#

Civil Service Pigeon

tardy mango
#

This is all you had to write

earnest mirage
#

I wanted to be as comprehensive as possible, covering all cases without exception

#

Just using the definitions

cloud hound
#

I guess I'll also demonstrate the contradiction idea I suggested before, as another example of a shorter proof

tardy mango
earnest mirage
#

If B is empty, then there is no x in B

#

A, B, and C are sets, either they are empty or not

#

I tried working with subsets, but I couldn't find a way

cloud hound
#
\begin{theorem}
Assume $A$, $B$ and $C$ are sets. 
If $A \cup B = A \cup C$ and $A \cap B = A \cap C$, then $B = C$.
\end{theorem}
\begin{proof}
  Suppose $B \neq C$.
Then there exists an element in one of the sets that is not in the other.
WLOG, let $x \in B$ but $x \notin C$.
\begin{case}
  If $x \in A$, then $x \in A \cap B$ but $x \notin A \cap C$ and by Definition 3, so we have $A \cap B \neq A \cap C$.
\end{case}
\begin{case}
  If $x \notin A$, then $x \in A \cup B$ but $x \notin A \cup C$ by Definition 2, so we have $A \cup B \neq A \cup C$.
\end{case}
Combining these two cases, if $A \cap B = A \cap C$ \textit{and} $A \cup B = A \cup C$, then $B = C$.
\end{proof}
flat frigateBOT
#

Coolempire93

cloud hound
#

And here we don't need to check the empty case because we have equality in the first place if both are empty

earnest mirage
cloud hound
#

Ah makes sense

earnest mirage
#

That is why I'd like to know if the proof looks good

cloud hound
#

I guess the way to do it directly in less steps would be (and then after I finish this one I'll look at yours)

earnest mirage
#

I appreciate your comments on proofs, even if it's not clear to me because I'm learning how to write proofs

earnest mirage
cloud hound
#

Your proofs looks good

#

Only change I would make would be to polish some wording

#
\begin{proof}
Let $A$, $B$ and $C$ be sets. 
Then either $A$ is empty or $A$ is nonempty.
First, suppose that $A$ is empty.
If so, then $A \cap B = A \cap C = \emptyset$ holds.
Also, $A \cup B = B$ and $A \cup C = C$, so because $A \cup B = A \cup C$, we have that $B = C$.

Now, suppose that $A$ is nonempty.
If $B$ and $C$ are both empty, then $B = C = \emptyset$, which is what we wanted to prove.
Suppose then that one of $B$ or $C$ is nonempty.
\begin{case}
Without loss of generality, let $B = \emptyset$ and $C \neq \emptyset$.
Then $A \cup B = A$, and since $A \cup B = A \cup C$, we have that $A = A \cup C$.
On the other hand, $A\cap B = \emptyset = A \cap C$.
Because $A$ is non-empty, $A = A \cup C$, and $A \cap C = \emptyset$, we must have that $C = \emptyset$.
Hence, $B=C$.
\end{case}
\begin{case}
Lastly, suppose $B \neq \emptyset$ and $C \neq \emptyset$.
Let $x \in B$.
Now, either $x \in A$ or $x \notin A$.
If $x \in A$, then $x \in A \cap B$.
Since $A \cap B = A \cap C$, then $x \in A \cap C$, which means that $x \in C$.
On the other hand, suppose $x \notin A$.
Then $A \cup B$ holds because $x \in B$.
And since $A \cup B = A \cup C$, and $x \notin A$, it must be that $x \in C$.
In either case, $x \in B$ yields $x \in C$, so, by the definition of the subset, $B \subseteq C$.
By the same argument, we may show that $C \subseteq B$.
Hence, as $B \subseteq C$ and $C \subseteq B$, we have $B = C$.
\end{case}
Therefore, in any case, if $A \cup B = A \cup C$ and $A \cap B = A \cap C$, then $B = C$.
\end{proof}
flat frigateBOT
#

Coolempire93

cloud hound
#

There's more I would change if it were mine but I tried to stick mostly to structural changes to lower the length

#

But in general words are preferred over symbols where the meaning is clear, for the sake of the reader and clarity

safe radishBOT
#

@earnest mirage Has your question been resolved?

cloud hound
#

Ah actually case 1 is impossible

#

You begin by assumine B =/= C

#

And derived a contradiction at that

#

Because you said C nonempty and showed that C empty

#

Making B /= C impossible, i.e. B = C

#

It's a simple fix

#
\begin{proof}
Let $A$, $B$ and $C$ be sets. 
Then either $A$ is empty or $A$ is nonempty.
First, suppose that $A$ is empty.
If so, then $A \cap B = A \cap C = \emptyset$ holds.
Also, $A \cup B = B$ and $A \cup C = C$, so because $A \cup B = A \cup C$, we have that $B = C$.

Now, suppose that $A$ is nonempty.
If $B$ and $C$ are both empty, then $B = C = \emptyset$, which is what we wanted to prove.
Suppose then that one of $B$ or $C$ is nonempty.
\begin{case}
Without loss of generality, let $B = \emptyset$.
Then $A \cup B = A$, and since $A \cup B = A \cup C$, we have that $A = A \cup C$.
On the other hand, $A\cap B = \emptyset = A \cap C$.
Because $A$ is non-empty, $A = A \cup C$, and $A \cap C = \emptyset$, we must have that $C = \emptyset$.
Hence, $B=C$.
\end{case}
\begin{case}
Lastly, suppose $B \neq \emptyset$ and $C \neq \emptyset$.
Let $x \in B$.
Now, either $x \in A$ or $x \notin A$.
If $x \in A$, then $x \in A \cap B$.
Since $A \cap B = A \cap C$, then $x \in A \cap C$, which means that $x \in C$.
On the other hand, suppose $x \notin A$.
Then $A \cup B$ holds because $x \in B$.
And since $A \cup B = A \cup C$, and $x \notin A$, it must be that $x \in C$.
In either case, $x \in B$ yields $x \in C$, so, by the definition of the subset, $B \subseteq C$.
By the same argument, we may show that $C \subseteq B$.
Hence, as $B \subseteq C$ and $C \subseteq B$, we have $B = C$.
\end{case}
Therefore, in any case, if $A \cup B = A \cup C$ and $A \cap B = A \cap C$, then $B = C$.
\end{proof}
flat frigateBOT
#

Coolempire93

cloud hound
#

All I did was remove where it said 'and C =/= emptyset'

#

We don't need to assume it (because we never use it)

#

Instead, we derive that C = emptyset = B

earnest mirage
#

Yes, from B empty we get C empty, so B = C

cloud hound
#

Actually we can extend the reasoning further to simplify

#

Rather than talking about 'both nonempty' or 'both empty'

#

Just consider 1 of the sets

#

You said either A is empty or A is nonempty

#

Now either B is empty or B is nonempty

#

In the first case we derive that B = C

#

In the second case we have case 2

#

Because the reasoning of case 1 could be applied to C, we do not need to check when C is empty, and can immediately jump to both nonempty

#

(further trying b nonempty and C empty leads to the same contradiction that I removed above)

#
\begin{proof}
Let $A$, $B$ and $C$ be sets. 
Then either $A$ is empty or $A$ is nonempty.
First, suppose that $A$ is empty.
If so, then $A \cap B = A \cap C = \emptyset$ holds.
Also, $A \cup B = B$ and $A \cup C = C$, so because $A \cup B = A \cup C$, we have that $B = C$.

Now, suppose that $A$ is nonempty.
WLOG, consider set $B$. $B$ must either be empty or nonempty.
\begin{case}
Suppose $B$ is empty.
Then $A \cup B = A$, and since $A \cup B = A \cup C$, we have that $A = A \cup C$.
On the other hand, $A\cap B = \emptyset = A \cap C$.
Because $A$ is non-empty, $A = A \cup C$, and $A \cap C = \emptyset$, we must have that $C = \emptyset$.
Hence, $B=C$.
\end{case}
\begin{case}
Now suppose $B$ is nonempty. Because $B$ was chosen without loss of generality, we may also suppose that $C$ is nonempty.
Let $x \in B$.
Now, either $x \in A$ or $x \notin A$.
If $x \in A$, then $x \in A \cap B$.
Since $A \cap B = A \cap C$, then $x \in A \cap C$, which means that $x \in C$.
On the other hand, suppose $x \notin A$.
Then $A \cup B$ holds because $x \in B$.
And since $A \cup B = A \cup C$, and $x \notin A$, it must be that $x \in C$.
In either case, $x \in B$ yields $x \in C$, so, by the definition of the subset, $B \subseteq C$.
By the same argument, we may show that $C \subseteq B$.
Hence, as $B \subseteq C$ and $C \subseteq B$, we have $B = C$.
\end{case}
Therefore, in any case, if $A \cup B = A \cup C$ and $A \cap B = A \cap C$, then $B = C$.
\end{proof}
flat frigateBOT
#

Coolempire93

earnest mirage
#

How did you set your Texit?

#

I see that you used the triple ticks to format LaTeX

#

Well, you can DM me if you like to

cloud hound
#

,texconfig autotex_level

flat frigateBOT
#
Configuration options for `autotex_level`

How strict the parser is when looking for LaTeX in your messages.
​ Current value: WEAK
​ Default value: WEAK
Accepted input: One of the levels listed below.

LaTeX Levels

CODEBLOCK: The strictest level, require a tex or latex syntax codeblock.
​ ​ ​ STRICT: Also recognise environments, $$...$$, \(...\) and \[...\].
​ ​ ​ ​ ​ WEAK: Also recognise paired single dollars, i.e. $...$.

cloud hound
#

The triple ticks is what's called a codeblock

earnest mirage
#

Yes, I forgot the name of it, I used with my notes in markdown

earnest mirage
#

.close

safe radishBOT
#
Channel closed

Closed by @earnest mirage

Use .reopen if this was a mistake.

cloud hound
#

No problem! 🙂

earnest mirage
#
\begin{proof}
Let $A$, $B$ and $C$ be sets. 
\begin{case}
Suppose $B$ is empty.
\end{case}
\begin{case}
Now suppose $B$ is nonempty.
\end{case}
\end{proof}
flat frigateBOT
#

Mor Bras
Compile Error! Click the errors reaction for more information.
(You may edit your message to recompile.)

cloud hound
#

Yes, but you have to put case into your preamble

#

For that to work catthumbsup

safe radishBOT
#
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faint glade
#

Why do we not pay attention to the -a here? $\frac{a^2}{-a^4}$

flat frigateBOT
#

Vortac

faint glade
#

Like, the result when simplifying is $\frac{1}{a2}$ right?

flat frigateBOT
#

Vortac

median vigil
#

that is incorrect

proud tree
faint glade
#

ahh okay

flat frigateBOT
faint glade
#

and $\frac{(-a)^2}{a^4} $ is $\frac{1}{a^2}$ because $(-a)^2$ makes a positive?

flat frigateBOT
#

Vortac

median vigil
#

no

proud tree
#

#

we have -(a²)

median vigil
#

you can't just move the - inside the square like that, you are changing the order of operations

faint glade
#

Its a separate question from the first one

proud tree
#

oh

faint glade
#

my bad for not clarifying

proud tree
#

then yes

faint glade
#

Thanks!

#

.close

safe radishBOT
#
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safe radishBOT
#
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lime frigate
safe radishBOT
lime frigate
#

<@&286206848099549185>

proud tree
#

!15m

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Please only use the <@&286206848099549185> ping once if your question has not been answered for 15 minutes. Please do not ping or DM individual users about your question.

rigid blaze
#

!15min

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Please only use the <@&286206848099549185> ping once if your question has not been answered for 15 minutes. Please do not ping or DM individual users about your question.

quick trellis
lime frigate
#

help me to solve it

#

i cant figure out whats the solution is

safe radishBOT
#

@lime frigate Has your question been resolved?

compact plover
#

use properties of similar triangles

lime frigate
#

ok let me try that

safe radishBOT
#

@lime frigate Has your question been resolved?

shut gust
#

HEy

#

.close

#

.clsoe

#

.close

quasi bison
shut gust
#

Sry

#

i think its offline

#

🤔 Sry

safe radishBOT
#
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shut gust
#

Please Help I Got It Its System Is That

00000000.00110111
00000000= 0
00110111= .37
0011 .3
0111 .7
But I am Not Getting Correct Answer.Even Adding ^ i Couldnt UnderStand Pls Help

shut gust
#

@vagrant jolt

onyx tiger
shut gust
#

hey

onyx tiger
#

Hi

shut gust
#

can you help me

onyx tiger
#

No, idk binary

shut gust
#

What The

#

Nothing

onyx tiger
#

The ping is @ Helpers

shut gust
#

huh

#

so i will do it again

#

@ Helpers

#

This Dosent Work

onyx tiger
#

No space

shut gust
#

<@&286206848099549185>

#

Ok

#

Thx For kekw

austere goblet
#

btw, a friendly reminder to only use the ping once after 15 minutes have passed since the start of your session, so please don't spam, just in case.

shut gust
#

Ok

#

now Pls help

onyx tiger
shut gust
#

what both of you are doing playing with me or gonna help

#

Hey

austere goblet
#

last warning: please do NOT DM me for math help. I have pinged you once to tell you the same thing the first time you tried that. the next attempt will be met with a modping and a block.

shut gust
#

oK SRY

#

<@&286206848099549185>

#

.close

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#
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shut gust
#

.reopen

safe radishBOT
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@shut gust Has your question been resolved?

shut hound
shut gust
shut hound
#

Yea you wrote that

#

but where are you doing the conversion?

shut gust
#

in my mind

#

Just That

shut hound
#

Well you did it wrong

#

Try doing the conversion by writing it down

shut gust
#

Wait Leemme Do That

#

00000001.(0001)(0001)
|| || ||
1 . 1 1

shut hound
#

Hint: $(0.3)_{10} = (0.01\overline{0011})_2$

flat frigateBOT
#

@shut hound

shut gust
#

The Answer Should

shut hound
#

Of the question, sure

shut gust
#

But couldnt Gte That

shut hound
#

I mean yea, I see that

shut gust
#

Can You Send Me Solved Version Of That Question Just Once So Can Solve ALl Other My Self This will Help ME A Lot

shut hound
#

!nosols

safe radishBOT
#

As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.

shut hound
#

!noans

safe radishBOT
#

The purpose of this server is to help you learn; please don't ask for direct answers. Ask for guidance, explanations, or feedback instead.

shut gust
#

But

shut hound
#

I'm telling you though

shut gust
#

Ok

shut hound
#

the issue is you did your conversion wrong

shut hound
shut gust
#

OK Gimem THat

shut hound
#
$(0.3)_{10} = (0.01\overline{0011})$\\
$(0.37)_{10} = (0.3)_{10} + (0.07)_{10}$\\
$\implies (0.37)_{10} > (0.3)_{10}$
shut gust
#

ok

#

Bye See Yaa

#

.clsoe

flat frigateBOT
#

@shut hound

shut hound
#

Aight

#

.close

safe radishBOT
#
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shut gust
#

.solved

safe radishBOT
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edgy isle
#

it's about 6.26 1

safe radishBOT
edgy isle
#

take $X=(0,1)\cup {2}\subseteq\mathbb{R}$ as a metric space, then $C=(0,1)$ and $D={2}$ are both non-empty, closed and bounded subsets.
But then if $r=2$ the latter property is obviously satisfied, but then isn't $h(C,D)=2$? Meaning that the $\Longleftarrow$ implication is wrong?

flat frigateBOT
tawdry plover
edgy isle
#

closed in X

tawdry plover
#

o oop

safe radishBOT
#

@edgy isle Has your question been resolved?

obsidian oracle
#

yeah it seems you need C and D to be compact for 1) to be correct

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steel roost
#

Hi,
I need to find zeros of a mimo control system, which is equivalent to finding s where P(s) loses rank.
For the case where D is a diagonal matrix, or same inputs as outputs, P(s) can be solved as an eigenvalue problem.

But what approach can I take if D isnt? How can I find the s where P(s) loses rank, while P isnt a square matrix

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steel roost
#

.reopen

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hard crest
#

i really don't remember that much of this part of linear algebra, but my brain is telling me the QR decomposition would be useful here

safe radishBOT
#

@steel roost Has your question been resolved?

steel roost
#

I found an approach online that uses the first n columns of matrices U and V to bring P into a square form and then solve the eigenvalue problem.

Do you think that could be a valid approach? And how can I interpret this multiplication: U_n* P V_n.

A non square matrix can ever only get a rank that equals the smallest dimension right? Is it maybe a projection into a space of all actual internal dimensions of P, where we can then look for values that reduce the rank of P?

hard crest
#

A non square matrix can ever only get a rank that equals the smallest dimension right?
correct, an m x n matrix has a maximum rank of min(m, n)

#

oh singular value decomp. yeah sure

steel roost
#

i know that the rank is equal to the number of non zero singular values, but its still very hard to imagine what to do exactly

#

since i still need to find a way to solve for s

hard crest
#

yeah i'm not sure that actually helps you :/

safe radishBOT
#

@steel roost Has your question been resolved?

steel roost
#

thanks for the help 😅

safe radishBOT
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slender steeple
#

hi, how do you make a confidence interval for the population variance in excel

slender steeple
#

<@&286206848099549185>

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slender steeple
#

im looking for the confidence interval of the population variance

#

which uses the chi square distribution

vale vessel
#

but i'm not 100% i'm sure i'm understanding what you're asking, so i'll let someone else take it (am slightly scatterbrained)

slender steeple
#

not using it for independence tests on hypotheses, sorry

#

i think

#

its time to ping helpers

#

<@&286206848099549185>

vale vessel
#

i also imagine you could just hardcode a formula from the chi squared variance formula, since i'm not sure excel has a built in function for the thing you are attempting to calculate

slender steeple
#

i see

#

is there a function for gettng the left-tailed value of a chisq dist?

#

im only seeing a right tailed value

vale vessel
#

unsure

#

you may just have to hardcode the formula

#

you're looking for this formula, right?

slender steeple
#

yeah

#

that's for stdev tho

#

but doesnt really matter

#

just square it

vale vessel
#

ye i mean your best bet is probably to just hardcode whatever formula you are looking for

#

as sucky as that is

slender steeple
#

aw man

#

i have to actually type shit now

vale vessel
#

the good news is that ${\chi}_{1-a/2, N-1}^2$ is constant

slender steeple
#

yeah

#

but how does one get the value of that

flat frigateBOT
#

Mirror

slender steeple
#

in excel ofc

vale vessel
slender steeple
#

is it just =chisq.inv.rt

#

oh thanks

gray mulch
safe radishBOT
#

@slender steeple Has your question been resolved?

pearl furnace
#

how to add and subtract like terms

vale vessel
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burnt nymph
#

Hey guys how to approach identity based q

safe radishBOT
quasi bison
#

general questions like this are better in #study-discussion, but also what do you mean by "identity based q"?

#

are you talking about questions that go "prove such and such trig identity"?

burnt nymph
#

. close

quasi bison
#

it's .close without a space

burnt nymph
#

.close

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twin warren
#

do i just overtake this now…. how do i get a fresh help page

quiet plume
#

It claims it automatically when you write something in a free channel.

#

What do you need help with?

twin warren
#

How can I graph a dual cone with 2 real axes and one imaginary axis?

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@twin warren Has your question been resolved?

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river sundial
#

Hello. Can someone look over my work please I am sure I did the steps right but I’m lost at the end

river sundial
lone void
#

i dont think it needed to be this lengthy

river sundial
#

practicing. on the exams i have to show every step

#

;/

severe pond
#

u = x^2 + 16 maybe

lone void
#

x^3 sqrt(x^2+16) can be written as (x^2)(x)sqrt(x^2+16) and u can take x^2+16=t

severe pond
#

yea

#

x^2 = u - 16

#

and just do power rule after distributing

river sundial
#

so was the answer wrong? or is it just a format issue when i do the final step when i take the limits

#

bc honestly its a lengthy trig sub problem yes but i dont see any mistakes tbh

severe pond
#

we are suggesting an easier way to do this

#

trig sub is ugly

#

i certainly didn’t bother reading through 20 lines of work

river sundial
#

yes but on my exam this is what the professor looks for

#

ahh

severe pond
#

i don’t think you understand our approach

river sundial
#

make sure that there is no cheating

#

ima just close this and figure it out ig thanks anyway

severe pond
#

🤔🤔

#

are you sure

#

i can write out the approach

river sundial
#

ur advice was just do it better im telling u this is practice ill get it

#

thank you

#

.close

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severe pond
#

$\int_0^4 x^3 \sqrt{x^2 + 16} \dd{x} = \int_{16}^{32} \frac{u - 16}{2}\sqrt{u} \dd{u}$

flat frigateBOT
quasi jewel
#

so like i wanna calculate the amount of light years it takes to drain out a femboy

#

yall can answer that or nah

#

💔

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hushed helm
safe radishBOT
hushed helm
#

this is as close as i could get

#

what do i do

bitter timber
#

were you given any other context

#

like a family of functions to look at

hushed helm
#

no blobcry

#

this unit is combined functions tho

#

so most likely multiple

#

stuff

bitter timber
#

kind of just eyeballed

#

but maybe something like this?

hushed helm
#

wow

#

youre a genius

#

how did u do that

#

thank u sm

bitter timber
#

so i kind of visualized a "trend line", you can sort of see that the function goes down by 3 ish after 4 blocks to the right, so that suggested a "mean" of y = -3/4 x

then the oscillations come from adding a sine component (not cos bc we have 0 at x = 0), so I just played with the sine coefficient until the oscillations looked comparable

hushed helm
#

woahh

#

i see

#

thats super neat

#

thank you so much

neon vapor
#

you can kinda compare peaks and troughs

#

it barely increases from trough to peak and then decreases by a lot from trough to peak

neon vapor
hushed helm
#

my teacher so weird

#

its okay tho

#

because shes super nice

#

.close

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#
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glass edge
#

The total of 4 values is 50. Another value is added and now the mean is 20. What was the 5th value

severe pond
glass edge
#

nothing

severe pond
#

brilliant

#

well

#

can you translate the first sentence into an equation

#

call the first four values x_1, x_2, x_3, x_4

glass edge
#

a+b+c+d=50

severe pond
#

or that

glass edge
#

(a+b+c+d+e)/5=20

severe pond
#

you're doing great

#

now solve for e

glass edge
#

e=100(a+b+c+d)

severe pond
#

🤔

glass edge
#

no

severe pond
#

you are forgetting something

glass edge
#

100/a+b+c+d

severe pond
#

no

#

$\frac{a + b + c + d + e}{5} = 20$

flat frigateBOT
severe pond
#

what happens after multiplying by 5

glass edge
#

$(a+b+c+d+e)/5=20\a+b+c+d+e=100\e=100-a+b+c+d$

flat frigateBOT
severe pond
#

parentheses

glass edge
#

$e=100-(a+b+c+d)$

flat frigateBOT
severe pond
#

good

glass edge
#

we know that a+b+c+d=50

#

so e=50?

severe pond
#

well done

glass edge
#

thanks

#

but

#

i have one more question

#

Intervals Frequency
10-19 4
20-29 7
30-39 4
40-49 6
50-59 2

#

Find median and mean

#

mean is easy

#

its the multiplication of interval by frequency

#

divided by the sum of frequency

#

but median.?

#

idk

viscid monolith
#

statistics is sooo long ago..

#

Median would be the middle value of everything

glass edge
#

could you help me tho

viscid monolith
#

Whoops. can't let my thoughts slip

glass edge
#

i think im wrong

glass edge
viscid monolith
#

No. I meant its so long ago since i took it

glass edge
#

oh

viscid monolith
#

Heres an example
Age groups :
1 - 10 : 15 people
11 - 20 : 30 people
21 - 30 : 7 people
31 - 40 : 2 people

#

If i were to put it into words
Age groups :
Kids ; 15
teens ; 30
young adults ; 7
not-so-young adults ; 2

#

If i find where exactly it hits the middle, that is
15 + 30 + 7 + 2 = 54
54/2 = 27

#

The median lies on the 27th position

#

So i would count from 0 to 27 starting from the first ordered list

#

The 27th position would be the teen age group.

glass edge
#

understood

viscid monolith
#

Uh but this is for even ya

glass edge
#

but then what the heck is the formula (n+1)/2 for??!

viscid monolith
#

If there are odd terms, you would get

#

yes u'd get that formula

#

Okay, heres an example

#

there are 5 males 6 females

#

total = 11 right?

glass edge
#

yes

viscid monolith
#

If you divide by 2 you'd get uh 5.5

#

So is the median females or males?

glass edge
#

so the 5.5th position

#

5+6/2

glass edge
viscid monolith
#

It cant be half male and half female right?

glass edge
#

female

viscid monolith
#

So we take (5+6 +1)/2 where 5+6 is your n terms.

glass edge
#

because 5.5 is approximately 6

viscid monolith
#

Then you'd get the 6th position

#

hence the median would be the female at 6th position

glass edge
#

how do you have two constants for one n term

viscid monolith
#

n is the total number of terms in that data set

viscid monolith
#

In this case, it would be 11. (For my example)

#

You can try for your question.

glass edge
#

and an alternate route you could do is add the frequency and divide it by 2 to get the position?

#

okay

viscid monolith
#

Uh yes.

glass edge
#

so for my question

#

there are 5 intervals

#

10-19
20-29
30-39
40-49
50-59

viscid monolith
#

In your case yes, the summation of the frequency would give you n number of terms

glass edge
#

(5+1)/2

#

6/2

#

3rd position

viscid monolith
#

Hold on. thats not how it works

glass edge
#

which is the 10-19

#

interval

viscid monolith
#

The intervals are just

#

A "group"

viscid monolith
#

Nono,

#

Okay let me try to draw it out

#

in this case, the median height is 168 where the third kid lies

glass edge
#

i see

#

but you did the exact thing though

#

for median

viscid monolith
#

So
161, 167, 168, 168, 172. -> Number of terms : 5
Since there are 5 terms, it is odd.
The position at which the median occurs is 6/2 = 3rd position

viscid monolith
glass edge
#

what

viscid monolith
#

This is the definition of median
*The median is the middle value in a dataset when numbers are arranged in order, dividing the data into two equal halves; *

glass edge
#

right

viscid monolith
#

Two equal halves

glass edge
#

so now we know its in the 4rd position

#

using the frequency

viscid monolith
#

if you take the sum of ur frequency what do you get?

glass edge
#

we determine that the median is in the 10-19 interval

#

correct?

viscid monolith
#

Intervals Frequency
10-19 4
20-29 7
30-39 4
40-49 6
50-59 2

#

Here's your uh original question

glass edge
viscid monolith
#

Can i say
a = 10-19
b = 20-29
c = 30-39
d = 40-49
e = 50-59?

glass edge
#

we know our median lies on the 3rd position

#

yeha

viscid monolith
#

Okay

#

how many a do we have?

glass edge
#

1

viscid monolith
#

Based on frequency

glass edge
#

oh

#

4

viscid monolith
#

How "frequent" does a occur

#

what about b?

glass edge
#

7

viscid monolith
#

aaaa,bbbbbbb,cccc,dddddd,ee

#

In this case let me write it this way

#

Do we see there is total of 23 terms?

glass edge
#

yes

viscid monolith
#

(I assumed ur calculation is correct)

#

okay is 23 odd or even

glass edge
#

od

#

odd

viscid monolith
#

Okay, i'll be showing you WHY we are using (23 + 1)/2

#

Okay, 23/2 is around 11.5 right?

glass edge
#

yes

viscid monolith
#

aaaa,bbbbbbb,cccc,dddddd,ee

#

11.5 lies between those two values

#

am i right?

glass edge
#

yes

viscid monolith
#

Can you definitively tell me

#

Is the median

#

b or c?

glass edge
#

no

viscid monolith
#

okay

glass edge
#

its b+c/2?

viscid monolith
#

Then what about we do this?

#

(23 + 1)/2

glass edge
#

24/2

viscid monolith
#

24/2 = 12

glass edge
#

=13

viscid monolith
#

12!!

glass edge
#

=12

viscid monolith
#

AHHAHA

#

aaaa,bbbbbbb,cccc,dddddd,ee

#

We see that we isolated it at "c"

#

Can you count on either sides, how many terms are there?

glass edge
#

11

viscid monolith
#

Are they equal?

glass edge
#

yes

viscid monolith
#

Then c that lies in the middle

glass edge
#

is median

#

okay

viscid monolith
#

is the median of two equal havles

#

halves

glass edge
#

but what if the number was even

viscid monolith
#

Then it makes ur life even simpler

glass edge
#

then you take the average of the two middle numbers

viscid monolith
#

Lets use the same case

#

aaaa,bbbbbb,cccc,dddddd,ee

#

I removed 1 b, you should get 22 terms

glass edge
#

okay

viscid monolith
#

22/2 is 11

#

Just nice, its still "c"

glass edge
#

yes

viscid monolith
#

hold on

#

Hehe

glass edge
#

i got 11?

viscid monolith
#

Nope yes, youre right

glass edge
#

on the left hand side i got 10

#

but on the right hand side theres 11

viscid monolith
#

So if we think about it right,

a,b,c,d,e,f

#

For this even set

#

The middle lies in between

#

c and d

glass edge
#

yes

viscid monolith
#

The following only works if its numerical values

#

for example
161, 162, 167, 172, 174, 178

#

The middle value is between 167 and 172

#

Then you will have to take (167+172)/2

#

This only works if your set is a numeric value and there are even terms

glass edge
#

..

#

is not the median just 167

#

?

viscid monolith
#

no, the middle value lies in between 167 and 172

glass edge
viscid monolith
#

oh i thought i had 6 terms

glass edge
#

,w median of 161, 162, 167, 172, 174

viscid monolith
#

ok my example is supposed to have 6 terms

glass edge
#

,w (167+172)/2

viscid monolith
#

Whatever it is this is a very simple representation of what im trying to say

#

If you have odd terms

#

Within the set, there is a certain term where the number of terms on the right side is equals to the number of terms on the left side

#

Eg.
1,2,3,4,5,6,7

glass edge
#

understood

viscid monolith
#

The median is 4 and there are 3 terms on each side.

glass edge
#

but what about intervals

viscid monolith
glass edge
#

are you supposed to take the average of intervals?