#help-36
1 messages · Page 181 of 1
Well you'd save yourself the exam fees
wait so were you applying for maths?
if i go to cambridge though I'd save myself the fees in london like 3 of my other uni options
damn
Well the london loans are bigger too tbf
wait so you did TMUA?
Yeah
wait what did you get
on tmua
because I am also applying for cambridge and imperial
7?
I had gotten as high as 8.9 when doing past papers
tbf "good enough" probably depends on your predictions
Only to choke and get 6.2 on the real thing
oh
Lowk I blame those pearson test centres
I had 3 x A* and 1 x A predicted
yeah that's probably why
A* in maths fm and physics, A in chem
I have 2 x A* and 1 x A predicted
You'll be golden with that score dw
my cs teacher isn't letting me get an A* predicted despite being less than 3% off the grade boundary for it
😭
Well that's the standard offer isn't it? U should be fine
true but the room for error is probably narrower
Damn, my chem teacher was similar
like I'd need stronger interview performance for cambridge
than the average applicant
and probably stronger TMUA results too
Well tbh I thought my interview went terrible
also again, that's if I get it
I mean it didn't go fantastic as I was pooled but still it mustve went good enough
ig everyone does
Basically what I'm saying is
Everyone thinks the interviewer expects u to be the next Terrence Tao
But it's not usually like that
true
idk how to perform "above average" then
Even if u fumble through the question, just explain ur thoughts and they might pick up on how clever u actually are in a non-interview setting or smth
if it's not about making as little mistakes
They just want abstract thinking ibr
oh yeah true
don't they only offer to 20-30% of people they interview
Ermmm I'm not sure tbh
What I do know is that they give out 2x as many maths offers as they have
ik
And chop half based on step
the thing is tho if you do well on step
then you're guaranteed a place
if you get 1,1 or higher
even with 1,2 they sometimes let you off
since they apparently check your working
so if you lost marks due to silly mistakes or something but had the understanding
yeah
I guess tbh though
i don't know a single person with only 2 A*s predicted who got a cambridge or even imperial offer
so like
idk
And assess u w/ the other 2-1s and 1-2s
Hm idk
oh so when that happens they take your a level fm scores
Yeah apparently
Or at least they did for this guy
I mean I'm sure they give offers to ppl predicted 2 A* since it still meets their standard offer
because step ii/iii requires fm proficiency anyways
yeah true
it's just idk concerning
You'd be surprised actually
that it seems rare
What can happen is STEP demands more revision time
And FM gets a bit neglected sometimes
oh yeah true
that's what happened when my original choice was oxford
I have heard of one instance where someone got 1-1 in STEP and A in FM
I neglected FM for MAT
Ngl ur a masochist bro
and sure i was getting like 70-90% in MAT mcqs but like
TMUA, MAT, and STEP??
my fm scores were BAD
Insane
i dropped oxford
for cambridge
because again
neglected fm
Fairs
and also i feel my chances are decently lower in oxford than camb
I'd disagree tbh
wait just curious what did you acc get in STEP
MAT is far easier
yea true but oxf has less places and they filter out applicants earlier
Yeah not good enough for cambridge
yeah true
ik someone who used to be in my school who got 1,1 in STEP
and is now at oxford
Well anyways at least I can flex that I got an offer in the first place so not all is lost
so he's marking any step papers i do
yea
i mean i doubt i'd get that far
tbh
Oh nice
with my predictions/gcses
You'll be fine
What kind of background we looking at?
No need to answer if its too invasive
i have extenuating circumstances (major depression) during gcses but I also go to a grammar school and pretty much most of the people i know got mostly 9s
I got mostly 7s and 8s
with one single 9
Well yk all offers they make are in the context of ur situation so
with the extenuating circumstances tho i think im still in the running
I wouldn't worry too much about the gcse grades
still i think for me they'd weigh interviews a bit higher
or the predictions tbh
than most other people
Plus u have the bonus of not being from a private school
true
If it helps I also got mostly 8s and 7s in my gcses
oh wait really
ok
i'm calm then
I think I had 3 9s, 2 7s, and the rest 8s
that's mostly 8s and 9s
not 7s
but uh
ok
And then a few odd ones like A, distinctions
i got 4 7s
ah i didnt do fsmq
still
nice
Oh wait yeah good point I guess my perception was a bit twisted
It's late ignore me 😭
oh dw
Did u do gcse FM then?
wait did you apply for maths or was it cs or another stem
yeah
Maths
Hey thats still solid
extenuating circumstances remember?
yea true
Oh niceee
I acc rly wanna get into some programming related maths but I didn't do CS A level
Anyways I enrolled for MSci maths even tho I'm not 100% sure I want a masters
you can probably try again for a msc if you have evidence of interest in cs
oh ok
Just bc I have the flexibility to move down to BSc if I like
yeah nvm
Whereas moving from BSc course to MSci integrated masters is trickier
I mean
I could still switch up after year 3
if you get a first class or something as a BSc
acc even without a first class
cant you still do a MSc at imperial
with a bsc
it can't be that hard to move surely
Idk if it would still be integrated masters tho
oh yea true
I may have to give up another year
Well either way tbh my course has python modules in year 1 and more optional programming modules later on
So I'll get to dabble in programming a little if nothing else
yea true you are in a good position either way at imperial
i think just make sure you do some internships
yeah they do
yeah
thats what i was gonna say
yeah
i think if i do a bsc at imperial or camb and get a first class
i'd acc try applying for mit
and us universities
U wouldn't want to complete the tripos?
for a msc? idk
i mean isnt a cs msc more useful than a maths msc to get into tech
Maybe, I'm no expert on CS
Well anyways as cool as MIT is
I don't think I could go uni there
For a year sure
But I couldn't live long term in the states
yeah idk if i would either
who knows tho
Plus nows not a great time to be a foreign student in america
Seems like a guarantee to get deported
yeah that's true
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was wondering in a)
we are gonna use this formula:
where we know what n is=
but is v= [ 1 0 0 , 0 1 0 , 0 0 1}?
or something else that i have missed?
!15m
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yea ik but i am rly in a hurry have the exam in a few hours ...
anyone plz? 🙂
<@&286206848099549185>
i am unsure what this formula is, but v should be a vector, judging by the notation
what's the full formula?
yes that the formula
for planes
thats the formula?
oh fr? weird
i only see v = (x_1, x_2, x_3) as a possibility
but if n is the normal vector of the plane, v dot n = 0
?
oh wait sorry that's (v-a) dot n = 0
well that's a matrix
you mean $\vec{x} = c_1\vec{e_1} + c_2\vec{e_2} + c_3\vec{e_3}$?
haseeb
it is, but im trying to figure out what you mean by "x is the identity matrix"
look
this is from a another exam
we need to do like this
but here is a line instead of plane
so the formula is a bit diff
but its almost identical
x is always the identity matrix (mostly) in this question
but i was wondering if it the same if it have a reflection in the plane
i have not seen a formula with a matrix to define a plane
usually it is two vectors
so i am unsure about this formula as you say it, sorry
nw fam
i think i am correct tho
double checked it with chat now
but i wanted to ask someone just if its 100% correct
.close
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If $P(E)=0.9, P(F)=0.8.$ Show $P(EF)≥0.7$
wai
So I have to write $E \cup F$ as the union of 2 dijoint events
wai
I'm losyt honestly
oops., yes
Consider 2 cases
I guess $S \setminus(E^C \cup F^c)$?
When E ∩ F = {} and when E ∩ F ≠ {}
wai
hmm?
Wait am I being dumb
Okay I misread the question
.>
Use that P(E ∪ F) = P(E) + P(F) - P(E ∩ F)
Yeah, I used something similar I think
Sorry I read a <= instead of >= in the question and confused myself
I would now like to prove Bonferroni's inequality
The way I visualise this problem though is considering the unit interval
That is P(EF)≥P(E)+P(F)-1
If I want 2 sets of lengths 0.8 and 0.9 then somehow the 0.9 and 0.8 sets needs to intersect at least 0.7 of the time
If you just for simplicity sake have the 2 sets as intervals then you’re kinda sliding these bars around looking at the overlap
The left hand is bounded by 1 from above
It’s a probability so it’s bounded
Do you agree that this is true
yes
Do you also agree that 1 >= P(E ∪ F)
Then it’s straightforward
_<
got it
Have a few more questions I would like to solve here( All probability)
Show $P(EF^C)=P(E)-P(EF)$
\
$P(EF^C)=P(E)+P(F^C)-P(E \cup F^C)$
\
wai
You just fiddle with the sets a bit
yeah
I think it’s good to just wrestle with them for a bit
Like if you don’t get it immediately just keep trying
There aren’t all that much you can try so you’ll find it eventually
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Can someone validate my claim before i make a fool of myself being snarky?
Im helping zin with this problem and my claim is that the first and second derivative cannot be both strictly greater than and less than zero at the specified points
It should be (-inf,0) and (0,inf)
and (-2,2) etc
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$$\begin{problem}
Let $c$ be a nonzero real number. Suppose that
[
\left(c+\frac{1}{c}+1\right)\left(c+\frac{1}{c}\right) = 1.
]
Determine the value of
[
\left(3c^{100}+\frac{2}{c^{100}}+1\right)\left(c^{100}+\frac{2}{c^{100}}+3\right).
]
\end{problem}
$$
.
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
Mb lemme type it
Let be a nonzero real number. Suppose that
\left(c+\frac{1}{c}+1\right)\left(c+\frac{1}{c}\right) = 1.
\left(3c^{100}+\frac{2}{c^{100}}+1\right)\left(c^{100}+\frac{2}{c^{100}}+3\right).
If (c+1/c+1)(c+1/c)=1
Solve (3c^100+2/c^100+1)(c^100+2/c^100+3)
Ima close it and type it correctly
. Close
.close
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how can we study the sign of tanx-x
using derivativs
the first derivative is sec²x-1
which AFAIK we cant reallybound it
.close
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any trig identities you can do with that?
i fugired out man
ok
btw i dont think you should reply in a closed channel
it sounded like you didnt resolve the question
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i closed it but i didnt specify mb then
.close
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can someone explain the definition of quotient set?
A quotient set is a partition
Quite literally as simple as that
and if possible the fundamentaltheorem of equivalence relations
is more than that
Simply somewhat more formal
Trust me, at its core they're purely that
not every partition is a quotient set
Given an equivalence relation R, R induces a partition(quotient set) and any partition induces an equivalence relation
Actually, yeah
Pick some random set X and your favorite partition P of X
Define an equivalence relation as follows: x~y iff x and y belong to the same set of the partition
~ is symmetric, reflexive and transitive
this is funda theo of equiv rela?
X/~ will again simply be P, the partition
Yup
The fundamental theorem of equivalence relations tells you this
a partition on a set is just a partition on a Set but a qoutient set of an equivalence relation is a partition on the set that the equivalence relation is defined on, such that every element in the partition is the distinct equivalence classes of the set that the equivalence relation is based of
is a mouthful, you understand?
I get what you're saying, I have worked with quotients multiple times
What I want to tell you is this: equivalence relations and partitions are in perfect correspondence
For any partition, there is a unique equivalence relation that induces it
And for any equivalence relation, there is a unique partition that defines it
Recall that any two given equivalence classes of an equivalence relation ~ are either equal or disjoint
From this follows what I told you above
yes, from which theorem you got this?
has this been proven, because i would appreciate it
Don't recall it having a name, it's just a lemma
I'll prove it to you right here
Consider a set X and an equivalence relation ~, choose two equivalence classes [x] and [y] from the quotient set, which we'll assume distinct
Assume then that their intersection is nonempty, choose some z such that z∈[x] and z∈[y], this then implies that z~y and z~x, however, by transitivity and symmetry we then have x~y, applying transitivity we obtain then that [x]=[y], as such, our assumption of a nonempty intersection must be false
To show that a quotient set is a partition you simply need to apply this and reflexivity to show that no element can be left outside of all the classes
Finally, for the second part of the theorem, that any partition induces an equivalence relation, simply apply this
Reflexivity, symmetry and transitivity are easily checked
how does it follow the union of the equivalence classes is the original set
Assume there exists some element z∈X such that z∉UX/~, then z is in no equivalence class, which implies z∉[z], in other words, ~ is not relfexive
I've worked through my fair bit of set theory
Read Munkres' Topology chapter 1 on set theory on its entirety and am now wrestling with some more "formal" set theory
I found quotient sets to be a useful way to "isolate what's important"
how to prove the distinct number of equivalence classes is equal to the cardinality of the quotient set
By definition, no?
The quotient set will only include equivalence classes
As such, the number of distinct classes will be its number of elements
what's your definition of quotient set, does munkres define it?
The same as yours, a set of equivalence classes
And tbh I don't recall the exact definition Munkres gave
He was done with equivalence relations and quotients quite early
that's like a characteristic of it, but in set builder
damn
you said every equivalence relation induces a partition or every equivalence class onduces a partition?
X/~={x∈P(X):((z,y∈x)⟺(z~y))} would be the best I could come up with rn
Every equivalence relation induces a partition
With the quotient set being the partition in question
Yeah, he got quite far, by the end of Munkres I had proven equivalences of choice, worked with well-orderings, and much more
He also introduced zorn's lemma, ordering relations, the recursion theorem, and had some very interesting(but quite tough) exercises
this looks fine dude, interesting you could came up with it that quick
Well, thank you
what does topology has to do with this
Topology is all about sets
a friend of me asked me to define quotient set like half an hour ago and couldn't come up with the definition from the top of my head, i guess i need to prove more things with equivalence classes
So it requires some really strong background on (at least naive) set theory
Dw, you'll eventually get used to them, they show up quite frequently
And can be a handy tool at times
regarding an equivalence class of an element in X, how is it every element in the equivalence class is a candidate for class representative?
Because a class representative is no more than an arbitrarily chosen element of the class
So naturally, any element qualifies
Now, granted, you'll usually make use of something to choose the class representative
But any element could be one without a problem
is it possible that: a relation on A which is an equivalence relation is it possible that one of the equivalence classes of an element in A is empty? is it possible the quotient set is empty?
1:No, 2: only if X is empty
If an equivalence class is empty, there exists some element which is not equivalent to any element in the set
This includes itself, so the relation wouldn't be reflexive
2: the union of all the classes in the quotient set must conform the original set, if the quotient set is empty, then the union is empty and the original set is empty
What I mean by this is "if an element is not equivalent to any element it is not equivalent to any, including itself"
is defining an equivalence relation on an empty set imposible?
From this, it follows an empty class implies the relation is not an equivalence relation
Have you heard about vacuously true statements?
yes but i don't have a good example of one
is it more like you know it when you see it?
or am i just clueless?
A formula is false iff its negation is true
(assuming consistency but I won't get there)
So Imagine I said ∀(x∈∅)(|x|=ℵ_8727)
Is this true?
what is that aleph 8727?
But in general, any universal formula about Elements of the empty set will be true
The aleph indexed by 8727
Getting back to this, though, recall a relation ~ is an equivalence relation iff:
1:∀(x∈X)(x~x)
2:∀(x,y∈X)((x~y)⟺(y~x))
3:∀(x,y,z∈X)(((x~y)^(y~z))->(x~z)))
Notice all these are universal formulas
So if we take X=∅, essentially any relation between two elements you can define will be an equivalence relation over ∅
However, of course, these are not of much interest
ok
so it's vacuously true its reflexive symmetric and transitive because there is no element inside {}
Yup
so any relation defined on the emptyset is a equivalence relation
we are not saying anything useful, but is cool u clarify me this trivialities
because it May become handy somehow later
Well, all equivalence classes being nonempty Is a somewhat important fact
One of the reasons why reflexivity is needed
let's say i have an equivalence relation on the emptyset
for example, x ~ y <=> |x| <= |y|
this valid?
because the equivalence class of any representative is a subset of the emptyset, and therefore empty
Only problem I could find here is that you haven't defined addition for "elements of the emptyset"
That is, I don't see how you could turn this into a formula
it's ~ defined on the emptyset
then, there are 0 dustinct equivalence classes
With ∅/~=∅
Yeah, and exactly cardinality 0
yes
wdym?
The equivalence classes being nonempty implies the union of the quotient set is the original set
in this case every equivalence class is empty
And it stops quotient sets from behaving in a strange way
Yeah, but of sets with elements
ok
"is it possible that one of the equivalence classes of an element in A is empty*?
You implicitly assumed A was a nonempty set
Hence why I simply answered it wasn't possible
Nah, dw
but is cool we revised multiple examples
Well, I hope this helped you
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How did they write AB = sqrt440(1+x + x^-1), either on expanding this term doesn't give much idea from where did they get it
they used the fact that the side of the second square sits along the hypotenuse in just such a way that by similar triangles:
(side of S₂) : (whole hypotenuse AB) = 1 : (1 + x + x⁻¹)
Since the area of the second square is S₂ = 440, its side–length is:
k = √440
not clear still
what about it
side of S₂) : (whole hypotenuse AB) = 1 : (1 + x + x⁻¹)
all are similar triangles, e.g. this diagram
yes
i didn't used similarity this this before ie ratio of the sides on one line segment
that is not clear
"yes" so what is unclear
the side of the second square sits along the hypotenuse in just such a way that by similar triangles:
(side of S₂) : (whole hypotenuse AB) = 1 : (1 + x + x⁻¹)
this explanation
actually how are you applying similarity on hypotenuse
<@&286206848099549185>
Are these the diagrams?
if FE = s then
BF = as/b
AE = bs/a
because ACB is similar to GFB is similar to AED
tan(ABC) = x = b/a, so AB = AE + EF + FB = s(x + 1 + 1/x)
@cedar obsidian Has your question been resolved?
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Does a (non constant) polynomial always have a complex root? why and whats the proof?
im just curious -w-
yes, and that statement is called the Fundamental Theorem of Algebra
which has many different proofs
The fundamental theorem of algebra, also called d'Alembert's theorem or the d'Alembert–Gauss theorem, states that every non-constant single-variable polynomial with complex coefficients has at least one complex root. This includes polynomials with real coefficients, since every real number is a complex number with its imaginary part equal to z...
"atleast one complex root" so this doesnt mean that a degree n polynomial must have n many complex roots, right?
it does, by induction!
oh cause factoring?
yes
once you prove that any nonconstant poly has at least one complex roots, this means you can start with a polynomial and pick off its factors one by one, bringing the degree down by 1 each time
That’s only possible when the polynomial has complex coefficients
Otherwise not always necessary
can you show some examples?
Oh
Let’s take quadratics
If all coefficients were real
Then if it had complex roots
It would always be two
And the roots would occur in conjugate pairs
if one root a+ib
Other would be a-ib
the other a - bi yea i know this one
Yes
@strange coral "complex" is taken in the inclusive sense here
we're not considering real numbers to "not be complex"
R ⊆ C and all
well I interpreted it differently
Mb
I was dealing with non complex coefficients
With imaginary part being zero
Otherwise, That would always imply that it would have complex root/ roots
i think you've introduced some confusion here
@lime crest do you have anything else to ask or anything else that's unclear
nope, thanks you two! :3
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Given $P(A|B)≥P(C|B)$ , show $P(A^C |B)≤P(C^C|B)$
wai
I was thinking of starting like so'
$P(A|B)≥P(C|B) \iff A \cap B \supseteq C \cap B \iff A \supset C \iff A^C\subseteq C^C \iff A^C \cap B \subseteq C^C \cap B \iff P(A^C|B)≤P(C^C|B)$
wai
first equivalence is false
Well isn't P(A \cap B) ≥ P(C \cap B) true?
and?
isn't A \substeq B \iff P(A)≤P(B)?
no
you should be able to come up with a counterexample in <1 minute
A= R; C= \C; B=Q
what
wai
$A={1,2,3,4}; B={1,2,3}; C={1,2}$
wai
- with what probability measure
- not a counterexample
I'll have to think a bit
Honestly, I haven't done probability measure yet ( we haave in class, I haven't reached there yet)
ignore the word then
what distribution
I dont even wanna know what you think P is if not a probability measure
Closed by @warm python
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.reopen
✅
if you just say A={1,2,3,4}, then P(A) makes no sense
you need to say how the probability of A is calculated
aka you have to specify the distribution
or the measure
specify how P works
@warm python
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Those are just the axioms of probability are they not
no
the axioms of probability say that P is a measure
they dont say what number P(A) actually is
I think using the word measure, or even distribution is probably confusing them when you only really need to know that P is a function from some event space to [0, 1].
You don't need to know that the event space must be a sigma algebra, or what a measure is for this kind of Venn diagram chasing.
measure is a term you can introduce when you do the axioms of probability
terms like uniform distribution should be known already
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He,lo
Hello
Eh
Hello
I’m a bit of tired and anxious but I want to maintain productive
I want a math game
That I can play rn
if you're tired and anxious then productivity is way lower on your list of priorities
that seems unproductive
https://mathtrainer.ai this is the best I can find
Relaxing math game
But it lacks computation that involves fractions
As well as logarithms
I want something to grab my attention
This activity has to be academic related
why?
I want to use my time wisely
using your time wisely ≠ dedicating 100% of it to academics.
You are right Ann
using your time wisely = knowing when to give your brain time to rest.
I like reading novel
excellent, read some novels then
remove one of "currently" and "rn"
Yes,they are the same in meaning
Try to fit as many calculations on a singular page as possible
It’s quite fun
or if you hate yourself, do that on a paper that already has stuff written on it
are you joking or serious
It’s more fun than doing it normally, that’s for sure
you didn't answer my question
Serious
then thats a terrible suggestion
fair enough
You would be productive though if it works for you
It’s not as bad of an idea as turning all the stuff into individual paper cutouts that you can rearrange however you please until you solve it
that might actually be fun now that I think about it but you’d need a bunch of cutouts
(Also doesn’t work for everything)
@jade fable Has your question been resolved?
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for this question the answer says base must be positive, why is this the case?
yes bases cannot be negative nor 1 nor 0
oh okay
is there any reason for this or proof i can see
just to understand
even if not ill just follow that lol
log_a(b) is the solution to a^x = b, which is supposed to exist and be unique
just think of 1^x=2 is this possible in the reals , same idea for 0 and the negatives
this is impossible yeah ok i get it
icic
if a=1 or a=0 then a solution either doesn't exist or there are too many of them
and if a<0 then a^x is a huge can of worms to even talk about
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can someone please help me with questions ii-v?
Can you show your work?
one sec
i took $x-1=e^{t}=> \frac{dt}{dx}=\frac{1}{x-1}, y(x)=Y(t), y'(x)=Y'(t)\frac{1}{x-1}, y''(x)=\frac{(Y''(t)-Y'(t))}{(x-1)^{2}}$
MichaelRafto
MichaelRafto
now i need the particular solution
i tried using $y_p=A(x-1)^{-1}$ and then deriving that 2 times but it doesnt seem to work
MichaelRafto
$y'_p=-A(x-1)^{-2}, y''_p=2A(x-1)^{-3}$
MichaelRafto
$(x-1)^{2}2A(x-1)^{-3}-4(x-1)(-A)(x-1)^{-2}-14A(x-1)^{-1}=(x-1)^{-1}$
MichaelRafto
$2A+4A-14A=1$
MichaelRafto
$A=\frac{-1}{8}$
MichaelRafto
$y_p=\frac{-1}{8(x-1)}$
MichaelRafto
...which isnt the particular solution
<@&286206848099549185> can't i just solve for x and not for t on this one?
I don't think you can guess that easily a particular solution, have you tried variation of parameters?
MichaelRafto
$y'_p=-Ae^{-t}, y''_p=Ae^{-t}$
MichaelRafto
$Ae^{-t}-5(-Ae^{-t})-14Ae^{-t}=e^{-t}$
MichaelRafto
$A+5A-14A=1$
MichaelRafto
MichaelRafto
$y_p=\frac{-e^{-t}}{8}$
MichaelRafto
$y_p(t)=\frac{-1}{8e^{t}}$
MichaelRafto
isn't that the same thing? <@&286206848099549185>
For some reason both are correct actually
I suppose though, you solution is not an actual particular solution but a possible linear combination of your homogeneous solution
Hmm though I doubt that actually
so $\frac{1-9x}{72(x-1)^{2}}$ is wrong?
MichaelRafto
No that also works, I checked on Desmos
huh
how do i get this one then?
ig it doesnt really matter since both are correct
,w simplify (1-9x)/(72(x-1)^2)-(-1)/(8(x-1))
Yes they should be equivalent actually
In the homogeneous solution we have c_2/(x-1)²
So you could redefine the constant c_2 in such way so that you end up with the particular solution they have
idk what that is
aight
I suspect they just chose a different approach or did variation of parameters instead of guessing
The proffesor's way is basically "take yp as Ae^nx" and find the particular solution for the equation"
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TOPIC: Absolute Value & Piecewise Functions. Missed math class friday, dont understand very much from the notes and needed further explanation. Thanks!
need help with this problem specifically, dont understand what im supposed to do but i tried to start it
heres an example problem i copied the answer for from the notes if it helps
Okay so what do you get about absolute values, lets start with those since they are fairly simple
absolute value is the distance of a # from zero
Thats one way to say it, that the modulus. But as a function it makes everything inside positive
so |-5| = 5
okay, yeah that makes sense
Which is basically to say, -5 is 5 away from 0
But for intuition it is simply, everything is positive
So with the first function, everything from 5 and beyond is positive and the absolute bars do nothing. and form 5 and below everything is negative and thus the bars flip every output inside
Now to find specific points or ranges remember this simple rule: If the inside is negative, to remove the bars multiply the parts inside by -1. So the first function is 2((-1)(x-5))-4=2(5-x)-4 from 5 and below. and 2(x-5)-4 for 5 and above
idk if im understanding what your saying, but i tried solving the equation you gave me, what do i do with this information
almost, the negative one is distributed to all elements inside the ||
Now that i look back, it was written correctly
my bad 😂
$\mqty( 2x-6 & x>5 \ -2x+1 & x<5)$
where did the 14 come from?
Wow my bad
jelly v20
its all good my friend
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how to find the intersection of y=3x+2 & y=4x-1
explainn 🤔
english isnt myfirst language so i probably know what u mean its just something different in my language , lol
samtidige ligninger
how did u know my first languagehello
Your status
but yes i believe i know such then 🤔 was watching a video of like
theyre both y= meaning u can put them together like 3x+2=4x-1 then find the x
So many people forget what information they display online
its a good song 😢
Seems good no ?
no because the issue is , i have no idea on HOW to find the x 🤔
like i never kknow when to add, remove, etc , on either sides
its quite confusing truly
Send all the x on one side
yes yes , i know such
but how 😆
And the others on the other side
Well then that's just manipulering af algebraiske ligninger
we really got the google translater here
I jest
but yes , i know what to do just not how haha
Try adding or subtracting the same quantities on both sides
Like you could add 2x on both sides and it doesn't change the equation
is it just trial and error then ? i have no way of knowing how to find my answer, onlu know that one side should be x and the other the answer
It's not trial and error no
woops
You have 3x+2 = 4x-1, what quantity can you add on the right side so that there's no more x there?
but how do i remove the 2 or 1?!
Ok so you did the calculation correctly but the operation isn't to subtract 4, it's to subtract 4x
3x+2-4x = 4x-1-4x => -x+2 = -1
Yes?
Right, well now you can add another quantity so that +2 disappears on the left
but then itd be -x+2-2=-1-2
would be
-x=-3?
Yes
You can also multiply by the same (non-zero) quantity on both sides
So as a last step here, you can multiply by -1
so -x*-1=-3*-1
would be
x=3?
Exactly
so this would be the final answer yes?
its just some training assignemnts but i think i hav ethe hang of it now
Honestly just need to trust my gut more because i was going the right way before asking 😭
Well you probably want the y value as well
o
now
how we do that
so currently we have (3,y) right
wat
Pick one of y=3x+2 or y=4x-1, replace x with 3, solve
right
(3, 11) is your answer
Or you can write x=3, y=11; depends what your teacher prefers I guess
yes! thank you
sent the assignment in at 10;45pm haha
its due september 2nd, was meant to send it early today but realized i forgot the last assignment so thank you for the help!
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Hi there! I’m having trouble with an inverse function problem, specifically with how to deal with these variable exponents. Here’s the problem and the work I have so far
Sorry for the quality, it says
a) find the inverse of the function f(x) = 4^x / 9+4^x
b) what is the domain of the inverse function?
Bring the y terms to the other side and factor 4^y
sorry I’m taking so long I’m trying to wrap my head around it haha
Do you know how to proceed, do you understand what happened?
I think I see what you did, I read it as 4^(yx) rather than 4^yx
yes, don't
Ok!! I understand, sorry about that. With this new equation, though, where exactly does the 4^y - 4^y * x come from? I understand 4^y(1-x) = x but I’m having a little bit of trouble understanding where you when from the factoring process
We moved the 4^y * x term from the right to the left side
I see! That’s what I got as well ^^
Yes, now how would you proceed
So from here, could we divide by (1-x) on both sides? In order to isolate 4^y
Yes
Ok! Thank you
One last step
Right, I’m a little unsure on how to deal with the variable in the exponent, would we be able to do anything with square roots?
Ok, got it! That makes sense I was wondering why we had this question in our logs assignment
There is a nice property, that is $\log_{a}(a^x) = x\log_{a}(a) = x$, \
provided that we have $a>0$ and $a\neq 1$.
I see! And that’s law 3 right?
law 3?
Sorry that might be something in my textbook only ^^’ we have 3 laws that we use for specific logarithms
Like this, I didn’t know if that was an actual name so that’s my bad
Yes, that would be law 3.
Specifically, we choose log with base 4 here because log_4(4)=1
Aaa ok!! I was just about to ask if I could do that, awesome!
Thank you so much for your help I really appreciate it, is it okay to just leave it like that? Does it still count as a function?
You can simplify the left side 
If you apply law 3, what will you get?
ohhh I see, ylog_4(4)?
I’m sorry I can’t think of anything😭 do they cancel out?
Yes
If the number inside the log and the base are the same, then the value is 1 😅
This is why we chose log base 4, specifically
Oh!!!! Okok that makes sense!
Any log with different base would have worked, but it would make things more complicated 
Aaa alright alright I see, thank you!
Awesome!! Ok that makes sense, thank you!! I really appreciate the help ^^
And I should be able to find the domain just by graphing, so I think I should be good… again tysm for the help, I hope you have a nice day!!
Oh if you are allowed, even better! 
If you are done with your channel, you may close it with .solved 
Yeah! My professor is very lenient about it thankfully, I’ll definitely challenge myself in the future to do it without graphing lol
That's the spirit!
Ty!! Is it better to use to close or solve command? I’ve been using close
Both work, I prefer solved
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Can someone explain to me why this is the answer and not 2piy(9-y^2)
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,,\int_{-1}^{1} \log [\frac{2-x}{2+x}], dx
!
I have no clue on how to proceed
King's rule
Oh
are those [] supposed to be floor?
I think its called GIF
same thing
use \floor
,,\int_{-1}^{1} \log \floor{\frac{2-x}{2+x}} dx
Percy
Percy
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
Im getting the same ig
Ok
$\lfloor \frac12 \rfloor$ I think? nope
How to check if this is a odd or even function
Ye i don't know how to do, can somebody help
To solve step by step
Alright, replace subtract x from the sum of limits
f(x) is your function
Now find f(a + b - x)
Are you sure?
1-1 is 0 isnt it