#help-0
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why?
yeah here is what is going on visually:
oh, because it is 1x^2
yeah
ok
okay so now we can simplify (3/4)/(1/2)
3 / 2
and how do we divide fractions? well we flip the bottom one and multiply them.
yeap
yep
(3/4)/(1/2)
When I have a fraction / fraction, i have just to simplify all the things?
but if i make the first fraction, the second fraction and then make the fraction with the result of both fractions i will get the same answer?
but it wouldn't be 3/4
so when i have fraction/fraction i have to simplify
no it wouldn't be 3/4
alright then
sorry what is "it" here?
2 - 1/ 2
no 2 - 1/2 is 4/2 - 1/2 = 3/2
u2
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Problem:
For a circle with a given radius, and 2 points present within that circle
Point 1: is always centered at 0,0 within the circle
Point 2: is dynamic, can be positioned anywhere within the bounds of the circle
The objective is to move P2 towards P1 following a given (arbitrary) trajectory
So the value I'm looking for is the next step, the dx and dy from where the point currently is, to where it needs to be
Complications:
The origin of P2 (it's last position or its trajectory's intersection with the circle) is unknown
The intersection between the trajectory and the circle is the origin
Specifications:
In this case, the trajectory is a sin curve
does anyone have an idea on the steps I need to take to resolve this problem?
@frail ingot Has your question been resolved?
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this is redundant! if x is less than 4, it's always less than 6
alright
x < 4
(y < 4) ⋀ (y^2 < 9)
y is less than four
the square of y is less than 9, so
y is less than 3, or less than -3
(y < 4) ⋀ ((y < 3) ⋁ (y < -3))
A ⋀ (B ⋁ C)
not sure how to draw this relationship with arrows of category theory
A ⋀ A can be written as AA, which is an identity function (?), as it equals to itself, or A
i don't know if B ⋁ C is an exclusive or, or an inclusive or
if y is less than 3, then y is less than 3
if y is less than -3, then y is less than -3
A -> A
B -> B
if (y = 2), then (y^2 = 4) ∴ (y^2 < 9)
if (y = -100), then y^2 = 10000 ∴ y^2 ≮ 9
values between -3 and 3 return True for y^2 < 9
a < y < b
-3 < y < 3
(y < 4) ⋀ (-3 < y < 3)
(y < 4) is redundant,
because (y < 3),
∴ (-3 < y < 3)
(x ≥ 0) ⋀ (x ≤ 0)
x is both greater and less than 0, and it is 0, at the same time, therefore x is 0
this can be written as x = 0
this is the mathematical world, in which everything is nothing
and where nothing is everything
0 < π < 10
π is greater than 0, but less than 10
7 ≤ p < 12
- p is less than 12, and it is greater than, or equal to 7
- 7 is less, or as much as p, while p is not so much as 12
@raven crag Has your question been resolved?
5 < x < 7
Five is not as much as something, while something is shy of seven.
x < 4
an unknown value is related to a number
3 > y > -3
There is a relation R 3 R y, and y R -3, so ∃ 3 R -3
x = 0
this is from Joyner, D Adventures in Group Theory
φ1 ⋀ φ2 → q
can be written as p → q
p is a conjunction, and a conjunction is true, when both φ1, and φ2 statements are true
i don't yet know how to relate φ1 to φn
data:
- objects: a collection ob C of statements
- arrows: for statements p, q ∈ ob C, a collection C(p, q) of arrows
arrow from p to q
structure:
- identities: for any statement p ∈ ob C, an identity arrow
identity arrow from p to p - composition: for any statements
p → q → r, a composite arrowg o f: p → r
@raven crag Has your question been resolved?
properties:
- unit laws: for any arrow p to q,
f after 1p=f=1q after f - associativity: for any arrows
a -> b -> c -> d,(h o g) o f = h◦(g◦ f)
Conjunction
φ1
φ2
...
φn
∴ φ1 ∧ φ2 ∧ . . . ∧ φn
i don't understand what shows the transitivity of conjunctions, and how to show that an infinity of premises are true
<@&286206848099549185>
φ1 ∧ φ2 ∧ . . . ∧ φn what are different strategies to show this conjunction is true?
specialisation
p ∧ q
∴ p
φn has to be true for the conjunction to be true
in fact, every premise has to be true
proof by induction
- base case: prove
ϕ1is true - inductive hypothesis: assume
ϕ1 ∧ ϕ2 ∧ … ∧ ϕkis true for somek - inductive step: show that if
ϕ1 ∧ ϕ2 ∧ … ∧ ϕkis true, andϕk + ϕk+1 is true, thenϕ1 ∧ ϕ2 ∧ … ∧ ϕk ∧ ϕk+1is true - conclusion: by induction,
ϕ1 ∧ ϕ2 ∧ … ∧ ϕnis true for alln
this completes the proof using mathematical induction
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How can i start doing addition and subtraction faster
by doing more addition and substractions
you can find some addition and substaction worksheets from the internet and stuff
You can do addition faster by multiplication.
It's fast to do 15 x 10 than add 15 ten times itself
no like for example
73+99
i wanna be faster by doing that
Oh
Yeah
theres too many things you could say
I usually give up
isn't there a way to do addition and subtraction faster
like a method
9+3 = 12 put 2 in the second place then 7+9 and add the one from soo 172
i think they wanna be faster at doing it from head
like from 73 + 99 --> (70 + 90) + (9 + 3) = 160 + 12 = 172
practice is probably a good way to start
Exactly
is basically the strat i use
put them down like this and start from right to left
then follow this
.
.
but just yeah just flesh out some addition questions
for subtraction good luck lo
for this i'd go 28 - 20 + 1
tbh i add while substracting as well lmao
oh i see
yeah if you are trying to do stuff on your head you can round the numbers and do the multiplication
or you can put them under like this to the paper then do the calculation which will minimize the amount of things you need to think
if it make sense
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What are some examples of functions that are Lebesgue integrable but not Riemann integrable? Except the Dirichlet function on rationals and non rationals
Thomae's function
@cinder parcel Has your question been resolved?
@minor pier thanks but it is still a derivative of dirichlet function and very similar. I am looking for some entirely different example
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@cinder parcel Has your question been resolved?
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como consigo falar em um canal em portugues?
falando
mas a maioria da rapaziada aaqui é gringa
joga no tradutor ou a imagem do problema que eles podem te ajudar
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do you know the intercept theorem (AKA thales theorem)?
No
maybe with this picture?
I'll search later, but I don't know yet
As E is a midpoint, so AE is half of DC, the intercept theorem says now that GA is half of GD. (in your example)
Sure
you can do the same with F.
With E too
so you get a relation from GH to AD.
so ad is half of gh
no.
why
ad is a half of GD.
AD is half of GD, GH is bigger then GD, so AD cant be the half of both.
oh
of course ha
what i am thinking here is
gea + ief + aefd + fdh = gih
i think i can do something with this information
thats true, but you are overcomplicating it. its much easier
oh, really
you need a ratio of two areas. first think about the formalas for this two areas.
yes, but you should keep in mind that the b and the h are different. to solve your example you need the ratio of the two b and the two h.
lets start with the b.
what is b in the parallelogram and what in the triangle
well, now we need a relation gh:AD
well. now about the h.
now put all together.
lets say the traingle is b1 x h1/2 and the parallelogram is b2 x h2
ok
if you tka the ratio triangle / parallelogram you get b1 / b2 times h1/h2 times 1/2
b1/b2 was ,,,
h1/h2 was ,,,
1/3 / 2/3 * 3/4 / 1/4 * 1/2 = 3/4
b1/b2 was 3
h1/h2 = 3/4
so you get 3 times 3/4 times 1/2
wait, b1/b2 = 3?
👍
what exactly?
I didn't know what i had to do to discover the result, but you did it so fast
all that we did was the intercept theorem?
yes to get gh/ad = 3 you use the intercept theorem twice. once for the left side (with E) and then for the right side (with F.)
and then once for the height (if you use the line EF)
so 3x intercept theorem. thats all.
)ok, 4 times there is one hidden application)
what is this hidden application?
in fact you need it alos for the height twice.
for half of bcfe right?
exactly.
just to remember, we firstly discovered the b of both polygons, then the height of both polygons, discovered the area of both and divided?
yes
we done this, but we could find the area first and then divide the areas right?
you dont know the areas, as you dont know the exact value of e.g. AD. you only know ratios and you are asked for a ratio.
(( b1 * h1 ) / 2 ) / (b2 * h2) = b1 / b2 times h1/h2 times 1/2?
( ( b1 * h1 ) / 2 ) / (b2 * h2) = b1 / b2 times h1/h2 times 1/2?
youre welcome
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is the concept of infinity binary?
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what do you mean by binary?
like it sounds weird, but i watch like anime and people say a specific character has boundless power, like infinite power.
But how does it work that he punshes weakly then
You should reopen if you plan to keep asking for help
oh how?
.reopen
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i just typed "hi" and then deleted it, i didnt know how that works
Anyways, the question does not make sense in my head
Open a new channel
how
Like you did with this one
we applying anime logic to real life with this one
!occupied
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is the concept of infinity binary?
you're gonna have to give some context to this question....
whar
imagine having infite power in your arms, can you punsh weak then?
what do you mean 'can you punish weak'?
punsh weak?
punch?
i mean very big strong guys with big muscles can lift up big weights but can also lift up a pencil so
i suppose yes
like can you just slap someone light
sure
Control of strengh is a different thing
but with infinite power? you cant just say something is fewer infinite or can you?
Infinite is not a number
That's a subjective question, and not really mathematical. But to answer your question, there's two ways to look at it:
If you have infinite strength, then
- Every action you do will be some percentage of your total power, so every action will have infinite power, or...
- Strength is a reservoir you draw from, and if that reservoir is infinitely deep, then you can output strength at any level you desire
Which outcome depends on the anime writing team
so, if this person moves at all they must use all of their strength with every movement?
taking one step explodes the planet?
thats what im saying, either you have infinite strength or you have not
You cannot have infinite strengh cause
where does math come into this other than the word "infinite"
but if we would put it in real life
then it's nonsense because infinite strength does not exist in real life
theoretical?
Neither
space is infinite right?
How do you know?
i dont know, thats why im asking to make sure
This is quite the mathematical conundrum
I have a marvelous proof of everything you said but its too short to write in this discord message
Strengh is measured with energy in the end
infinite space and infinite energy are different things.
Energy cannot be infinite
Physicists are presently unsure whether space exists beyond the known universe (which is finite in size)
!redir
This channel is only for on-topic discussion. Please take casual conversation to #discussion or #chill.
if i just put an x for energy there are infinite numbers for it or arent there?
Number is not equal to energy
yes, but that does not mean energy is infinite. And the amount of energy is still bounded
You can say the same with potatoes
what is the bound then? what is the final number for it?
Not quite. Potatoes are discrete, but energy is a continuum
total energy of the universe. Whatever that is (assuming current cosmological theories are more-or-less correct)
My potatoes help in math a lot
cant you go out of bounds then theoretically
cant you just take a higher number for you
you make it sound so easy
we say the final number is like 7, and now you just say 8 or something. or maybe 7.1
"can't I just exceed the total energy of the universe?"
yea why not
because that's everything
doesnt "everything" contain infinity?
not necessarily
depends on what "everything" is
Noop
because if energy is finite, then that's the cap.
If i say there's 10 people in a room, you can't just say "what if I talk to 11 of them"
it doesn't make sense. There are only 10.
If there is X 'amount of energy' in the universe, you can't just say "what if I use X+1 energy"
Natural numbers are infinity but they dont contain all real numbers
You're confusing "infinite" and "bounded". There are infinitely many numbers between 0 and 1, but each of those numbers is still bounded above by 1 and below by 0
another person can join the conversation though.
not if there's only 10 people in the room.
yea, but there is a 2, and after that there is a 3
I'm talking about only the numbers between 0 and 1
I'm giving you a hypothetical scenario
what if there would appear some other person for some reason, how does infinity work then?
If you're going to ignore that, then anything can be anything you want it to be
yea im talking about the concept of infinity
then sure. If you break the rules of the universe then yeah, whatever you want is possible.
(which is very common for manga writers tbh)
is there anything infinite in the universe? what about time?
This is an introductory undergraduate textbook in set theory. In mathematics these days, essentially everything is a set. Some knowledge of set theory is necessary part of the background everyone needs for further study of mathematics. It is also possible to study set theory for its own interest-...
i dont have 46 euros
nope, assuming our models are somewhat accurate, the heat death of the universe is inevitable.
But what if you had infinity euros??
is time influenced by heat or is heat meant metaphorically?
i couldnt pay then
Like, if youre solution to any problem is "What if we just change the rules" then sure. What you're saying will work, because you're going to change the rules to make it work.
So in response, yes your infinitely powerful person can touch lightly because he stores his infinite power in a different dimension until he needs it. How? The rules I changed to make it work like that.
Time is influenced by gravitational forces, heat is a macroscopic measurement of internal molecular motion that sums to zero net motion. They're unrelated
but how does infinity work then irl
Infinity is an abstract concept. It's not something you're just going to find in your backyard
yea i know
It's not like you look under your couch and you find "2" laying there
Infinity is an abstract concept related to sets. A set is infinite if it is not finite. A set is finite if its elements can be mapped bijectively to some set {1, 2, ..., n}
You can say whatever you want. You can say sdesdftgfdrfvcfrtgfvfr
Is it useful? Probably not
If you want to say something useful, then no, infinity+1 doesn't really have any mathematical value
does infinity have a value?
depends on how you define "value"
Is infinity a number? No
There are infinitely many numbers though
It is not
The closest you can get to saying "infinity has value" is if you consider cardinality (or limits), which requires set theory (or real analysis)
do you understand Infinity?
like if you think of infinity can you imagine in your mind what it is?
I think of infinity as one of two things
- The cardinality of a set is infinite if and only if it is not finite
- A sequence approaches infinity if it has no upper bound.
A sequence approaches -infinity if it has no lower bound
no. But infinitely many elements can be bounded (e.g. all the numbers between 0 and 1)
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@alpine sable Has your question been resolved?
I would split the integral and use sub for the right one and for the left it looks partial fraction decomposition will help
@alpine sable Has your question been resolved?
ye
𝔸dωn𝓲²s
It's not allowed with products/quotients
but with sums/differences it is
In that regard it's linear
For the left I give the hint x = 1 is a root
yea so you can write the denominator as linear factors
and apply partial fraction decomp
we can also do it together
hmm ok
up to you
I would do with you the left one
the right one is managble with sub
So the first thing I would do is write the denominator as factors
taking the hint that x = 1 is a root I would do long division or some like that
(x³ + x² - 2) : (x-1)
Let's assume you did that to save time
You would get this (x-1)(x^2+2x+2)
yes!
kisnar
yes!
Now notice that the other linear factor has complex roots
So what we would do using partial fraction decomp
$\frac{x^2+4}{(x-1)(x^2+2x+2)} = \frac{A}{x-1} + \frac{Bx+C}{x^2+2x+2}$
𝔸dωn𝓲²s
First step
yes!
the linear form Bx+C is used only for complex roots
now
2nd step is to multiply both sides by the denominator
$\frac{x^2+4}{(x-1)(x^2+2x+2)} = \frac{A}{x-1} + \frac{Bx+C}{x^2+2x+2} \quad \big | \cdot (x-1)(x^2+2x+2)$
𝔸dωn𝓲²s
𝔸dωn𝓲²s
So we at this
Now we want to do coefficient comparison
to find A, B and C
familiar with that method?
exactly!
We would need three eq. here
ok sure if you want to
yea no problem
i dont do it like but it's ok!
$x^2+4 = Ax^2+2Ax+2A + Bx^2-Bx+Cx-C$
yes!
yes!
yea if we look at 2nd and 3rd eq.
sure!
(A,B,C) = (1,0,-2)
yes!
yes
,,\int \frac{1}{x-1} : \dd x - \int \frac{2}{x^2+2x+2} : \dd x
𝔸dωn𝓲²s
The right one is a bit tricky
any idea?
ok good
,,\int \frac{1}{x-1} : \dd x -2 \int \frac{1}{x^2+2x+2} : \dd x
𝔸dωn𝓲²s
sine we got something with x² in the denom
what would that kinda resemble
do you know an integral with the form 1/x^2+...
yes!!
So here
we would like to get something like x² + 1
in the denominator
not quiet
we complete the square
do you know that?
ok so
for x² + 2x what key number would we need
to complete it
or do you understand my question haha
yes!
so
we can basically rewrite 2 = 1+1
,,\int \frac{1}{x-1} : \dd x -2 \int \frac{1}{x^2+2x+\textcolor{cyan}{1+1}} : \dd x
𝔸dωn𝓲²s
yea luckily!
imagine there wasn't a 1
like imagine
(x+2)² + 4
we would need to factorize 4
like
4((x+2)²/4 + 1)
and pull 1/4 as a constant
(x+2)²/4 + 1 = ((x+2)/2)² + 1
just so you know for the exam
but here luckily it works out to
,,\int \frac{1}{x-1} : \dd x -2 \int \frac{1}{(x+1)^2+1} : \dd x
𝔸dωn𝓲²s
𝔸dωn𝓲²s
yes
-2
is missing
as a factor
ok
good
I think you're good now
the left is self explantory I think
ok good
and the root integral is sub
video?
As a hint: try u = 1-x²
hmm
maybe
but seems too lengthy
yea then you have
,,\int x^3\sqrt{u} : \dd x
𝔸dωn𝓲²s
We need to replace dx too
yes
u = 1-x²
diff. both sides wrt x
u' = du/dx = -2x
dx = du/-2x
,,-\frac{1}{2}\int x^2\sqrt{u} : \dd u = -\frac{1}{2}\int (1-u)\sqrt{u} : \dd u
𝔸dωn𝓲²s
x² can be written as 1-u because of the substitution u = 1 - x²
And then the rest should be managble
using power rules
if you expand it too
𝔸dωn𝓲²s
𝔸dωn𝓲²s
\begin{gather*}
-\frac{1}{2}\int u^{\frac{1}{2}} - u^{\frac{3}{2}}\: \dd u
\end{gather*}
kisnar
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is there a tool for solving differential equations
at least give the answers cuz i'm solving some and I dont have the solutions so I dont know whether I'm doing it correct or not
Please don't occupy multiple help channels.
wolfram probably will
Get the free "Step-by-step differential equation solver" widget for your website, blog, Wordpress, Blogger, or iGoogle. Find more Mathematics widgets in Wolfram|Alpha.
yes
its tweaking, i gave it a simple equation and it gave no response
just typed the equation again in output 😭
@terse oak Has your question been resolved?
@terse oak Has your question been resolved?
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excuse me
How do you mean “rates of change”? Do you have an example of what you’re looking for?
ohh
sry i meant
sequences and series
oh
chapter 15
15
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a boy draws from a lot which has 6 balls inside numbered 1-6, if he tries to guess what number he gets every time he draws a lot not repeating a number twice, then the probability that be guesses all the lots wrong is?
I think of derangements but theres probably a much better approach
After 1 lot are we putting the ball back?
We could also do case work
Principles of Inclusion and Principle type
@inner pawn Has your question been resolved?
Derangement it is then
Oh right right
Derrangement of 6 things
So its D6/6!????
it's equivalent to a derangement problem because making your guesses after each draw offers no advantage over making your 6 guesses before the game starts
Yep yep
so like
Total cases are 6! Right
And i use formally for derrangement of 6 things
So itz D6/6!
?
yep
Thanks a lot!!!
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does someone know physics here i have a doubt in physics
post your doibert sir
!da2a
No need to ask “Can I ask…?” or “Does anyone know about…?”—it’s faster for everyone if you just ask your question! See https://dontasktoask.com/
my bad
basically if i have a cavity inside a insulating solid sphere....the electric field comes out to be some value (densityX vector connecting centre / 3 epsilonnot)....but if i assume a gaussian surface .. the electric fields comes out to be 0 .... why is it so
densityX: $\rho_X$? epsilonnot I'm sure is $\epsilon_0$
SWR
Your question isnt making much sense in its current form
He's using X for multiplication lol
just ignore the formula
gaussian surfaces only really work to find electric field magnitude if the setup is very symmetrical
no bro .. u can assume gaussion surface as you wish
it can be of any shape
But not necessarily find the electric field.
You can, but if the field isnt constant over the whole surface you wint be able to pull it out of the integral
you can make any arbtirary gaussian surface, sure, but unless you feel like actually calculating the surface integral over the varying electric field, you better abuse some symmetries
well gaussian surfaces can be any shape and any location, but assuming a constant electric field magnitude and direction on that surface (which is usually how they're used) is a much more stringent requirement
see in this case i am assuming gaussian surface to be exactly the size of cavity where there is no charge
the we can with confidence say that the flux through that surface is 0, since there is no charge enclosed... and nothing more, since we can (and do) find that the electric field comes in one one side and out the other, adding up to a net 0 flux
yeah so you're getting a 0 electric field inside the cavity (expected since there's no enclosed charge)
yes exactly but in reality there is some electric field inside it
it's not true that electric field inside a cavity is 0 if that cavity is not centered, the setup is probably something like this (in which case the electric field is uniform and nonzero)
so e.ds =0
e=0 then
that doesn't follow. flux can be positive or negative, so how can you know the positive and negative don't just cancel out?
in fact that's often how gaussian surfaces work
oh so you are saying that the integral of ds is actually making 0 not the E?
yes. the only way we can conclude the electric field is actually 0 from that is if we can be sure the electric field has some particular symmetry properties
ok i got it but 1 more question arises
if it is so then why electric field inside a uniform shell is 0
i can assume the gaussian surface of exactly of its size
then integral of ds is non zero?
generally we only consider gaussian spheres of either larger or smaller radius than the shell, because charge "exactly on the surface" doesn't fit nicely with gauss' law
well not exactly of its size but like nearly of its size
well anything smaller and the charge is not enclosed, so the flux must be 0. we know that if the spheres (gaussian and physical) are perfectly concentric, and charge is uniformly distributed, then the electric field due to those charges on the sphere's surface must only point inward or outward (since no direction is any different from any other direction, along the surface)
Because in this case, you actually respected the symmetry of the sphere, by choosing a spherical surface. In such a case the field will be CONSTANT over the surface, which allows us to write:$\int E \cdot ds = 0 \implies E \int ds =0 \newline \implies E(4\pi r^2)=0 \implies E=0$
ooh i got it
quickdoom
thanks a lot
yeah in the conducting sphere case, no direction is any different from any other direction (other than inwards vs outwards), so the electric field can't possibly point in any direction or vary in any direction than radially. but if the surface is not totally concentric that whole argument falls apart
oh wait if i assume the cavity exactly at centre of the uniform insulated sphere then will it be 0? due to symmetricity
yes
thanks @hushed locust
which agrees with the previous result that the magnitude of the field inside any cavity is proportional to the vector pointing from the center of the sphere to the center of the cavity, that vector is now just 0
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hello guys i have a conceptual problem about e. what is exactly e and why its differentiation is e
$e^x = 1 + x + \frac{x^2}{2!} + \frac{x^3}{3!} + \frac{x^4}{4!} + \cdots$
slayla
differentiating this termwise you’ll see we get the same thing back
what is the value?
there are different ways to look at it
one is e = e^1 here
this limit is another
i didnt understand
This is good explanation of why e^x is derivative of e^x
Try to differentiate both sides
RHS is just a polynomial, so it will be easy to differentiate
Then you will get de^x/dx = e^x
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Five young athletes were awarded prizes for sports achievements. The first one received PLN 1024, and each subsequent one received 𝑝% more than the previous one. The fifth athlete received 2,500 zlotys. Determine the amounts of the awards of the other three (from the lowest). how to solve it?
isnt it just 1024 * x^4 = 2500 ; solve for x and calculate 1024 * x^1 , 1024 * x^2 and 1024 x^3
this but x=1+p (i think so anyways)
to solve for p
y
i think its a string, either arithmetic or geometric
what is the task asking for? just the amounts of the other three?
or what does (from the lowest) mean
@flat loom Has your question been resolved?
The sum of the five initial expressions of a convergent geometric sequence is equal to LaTeX: 1Frac{40}{81}
1
40
81
. The sum of all the expressions of this sequence is from it by LaTeX: {frac{1}{162}
1
162
greater. Calculate the quotient of this sequence. Round the result to 2 decimal places.
@flat loom Has your question been resolved?
@flat loom Has your question been resolved?
@flat loom Has your question been resolved?
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Help I tried so many times what's the value of x
!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
show working pls
5! = 120 so thats 1 on rhs
I saw this question the other day
lol what
Also. 25^0 = 1
yo
take a new help channel
Bro foreseen the future !
idk how to do that
Pls help us
Same !
someone posted it here
u got me?
Its on paper I cant get o myphone rn
i did it already
To take foto
but like
can i get the answer
Pls teach
and then you do some factoring
simplify more
then you should get a quadratic
which gives you one answer
Please give answers I will use it later to review
AMBY PLSSS
Pleeease
can u type out where u got to
\sqrt[4]{64x}=\sqrt[4]{\frac{4120^{128}x^2+256120^{128}}{120^{128}}}
oh yea
it is 8
good job
$\sqrt[4]{64x}=\sqrt[4]{\frac{4120^{128}x^2+256120^{128}}{120^{128}}}$
wait what
why my latex not latex ing
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Amby
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need help idk why this is wrong
It would be nice to have graph of the functions
The issue is coming from the graphs
I will let you think about the problem
@slender sorrel Has your question been resolved?
Is there any way you can get around that
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I have a question about the tvm calculator
when i fill in all the details it comes out to that montly payment
but on the car website it comes out to almost 1k lower
theres a 5k downpayment which is why the PV is lower
@topaz locust Has your question been resolved?
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at the last step, you forgot to derive pi*r it seems
hmm?
delete that r and it should be fine
where
okay i removed the r but im still getting a bit off from the answer
answer key is saying it's 252
but im getting 207
nevermind I subbed in one wrong value
thank you so much
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Right. Ive made myself a script of the tasks ive finished, tips and tricks i got from others, etc. So id like to put the first 3 linear equations aside and move onto the 2nd part.
I remember tidbits but i cant say that im capable of doing it, so anyone knows how to solve? And id appreciate a " fool-proof" guide. Cause frankly, im an idiot at this.
I remember a fella telling me it had 2 methods of doing it? Systems of linear equations?
-x + y = -5
3x - 2y = -12?
do you want the method which is annoying and painful when the numbers are large or the method which is confusing
lets just go with elimination
basically in elimination you have to manipulate one or both of the equations so that when you add them one of the variables cancel out
Also, again, im a dumbass so id appreciate if we keep this as simple as possible (explaining-wise)
Huh?
i will give my own example
x+y = 4
x-y = 6
now what happens if we add both of the equations together
x+y + x-y?
yes on the other side
so it would be
(x+y) + (x-y) = 4 + 6
now when you add (x+y) and (x-y) together the y will dissapear
since y-y = 0
after that it should be obvious what to do
solve for x
x = 5
then pick one of the equations and solve for y by substituting x
x + y = 4
5 + y = 4
y = -1
Oh?
2x + 2y = 4
x - y = 6
now when you add both of these equations youll notice that no variables cancel out
(2x + 2y) + (x - y) = 10
3x + y = 10
no luck
Shouldnt it be 4x?
2x + x = 3x
so what you want to do is manipulate the equations so that you can cancel out one of the variables
it sounds complicated but basically
pick one of the variables, x or y
Ill pick x
2x + 2y = 4
x - y = 6
now make it so that when you add the two equations x cancels out
Huh?
ill just show you
2x + 2y = 4
x - y = 6
-2[x - y = 6]
-2x + 2y = -12
basically i multiplied -2 to both sides of the equation on the bottom
Oh wait nvm. I thought we jumped to some new task or step. Its the same task. Ok ok.
now we have
2x + 2y = 4
-2x + 2y = -12
when you add both of the equations, x will cancel out
leaving with
4y = -8
y = -1
it should be simple what to do from then
Determine what x is?
x - y = 6
x - (-1) = 6
x + 1 = 6
x = 5
ok now you try for problem one of the thing you solved
just try your very best
.
-x + y = 5
3x - 2y = -12
Lemme try a)
-x + y = 5
3x - 2y = -12
((Oh sorry. Scrolled up to reply and write-))
Hmmm
-x + y + 3x - 2y = 5 + (-12)?
if you try to do that nothing cancels out and youll be stuck
you have to manipulate one of the equations
Uhhhh
x
sure
now think of a way to manipulate the equations so that x cancels out when you add it
(you have to multiply on both sides)
Uhh
i need to go, the pentathlon is starting. Bye
-x + y = 5
Multiplied by 3...
-3x + 3y = 15.
9x - 6y = -36.
...thats...not getting me anywhere tbh. Worth a shot tho.
hey hows it going ?
you dont need multiply both equations
can only be one
Not that great. But howdy
Oh youre still here-
Idk i remember someone telling me to miltiply each of them.
i'm fine waiting football to restart , struggling on the a) of the second task ?
but your idea is correct
Yep
just multiply the first equation not the second one by 3 actually
-x + y = 5
3x + 2y = -12.
Now multiplying the first one by 3.
-3x + 3y = 15.
Oh i think i get it
...
No i dont. I just thought id get an idea if i said that outloud
no it's 15 on the right
it works sometimes
so
Btw
now you will have to add them to get rid of the x terms
Lemme see if i got this right
First we have the task.
-x + y = 5
3x + 2y = -12
We multiply the First line. AND ONLY THE FIRST LINE
By 3. ((Not sure if its always 3 but ima roll with it for now))
Then. We add the 2nd line to the first line after we multiplied it?
ok so the number who multiply depends on what you need to make the terms disapear while adding
Oh so if its like
-x + y = number.
And the lower is
5x + 4y = number.
We multiply by 5?
add or substract both works but in this case it's more efficient to add yes
yes!
-3x
- 3x. Well thats 0. Which is thanos snapped
3y - 2y = y
Y = 15 - 12
Y = 3?
okay and now do you know how to find x ?
Give me a moment
since you know y=3
-x + y = 5
I know y is 3
..wait.
X is in negatives-
Or does that not matter
Cause if it dosent. X is 2
x is a real numbers and y too it can be negative, positive, fraction, sqrt ... everything you can imagine so there is no condition on the values of x
Uhhhh
Not sure tbh
-x + 3 = 5
If we follow the same rules as before
We leave the variable on one side. And put the numbers on the other?
yes
-x = 3 + 5 ? ((It could be subtraction or adding. I just took a shot in the dark))
Here
ok
Oh. So its Subtraction?
we already end it
Sorry <:(
you do -3 both sides yes
y=-6 so -x+-6=5
-x = 3 - 5?
Huh
no you have -x +3 = 5
you substract -3 on both sides
what you get ?
-x + 3 = 5
-3. -3?
why do ya say sorry you're learning xd
-x = 2?
oh ok mb i just don't know what barely really means i messed up translation
didn't meant to be not kind
i wanted to say that we have reach the end of the solve
-x + y = 5
3x + 2y = -12
We multiply by 3 cause theres 3x.
-3x + 3y = 15
3x + 2y = 12.
We add them. -3x and 3x is 0, 3y -2y is y.
15 - 12 is 3. Y= 3.
Back to the first line.
-x + 3 = 5
Subtract by 3 on both numbers.
-x = 2
Btw. How can we tell when to subtract? :0.
for the system of equations or the 3 at the end ?
Overall
Like. Are there any requirements or signs that tell me " oh i gotta subtract"
if you have x+3=2 for example
you have a " + " on the left right ?
so when you want to get rid of it you will defeat him with a " - "
this is a questions of signs indeed
x+3=2 <===> x = 2 - 3 <====> x = -1
yes
or the right
?
Subtract both numbers by 4?
yes
the things i want you understand is no matter what side it is you have to substract when it's a + and add when it's a -
No?
?
Bad wi fi
oh okay
I said that making sure was i right or wron
Wrong*
So we add when its a minus.
Subtract when its a plus
