#help-17
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it's way more
2009 nd 1
Yes
i forgot to add sign
It was understood
how did u do this could u give me steps
Factor the original expression
i don't know how to factor
its my doubt dude
could u send me steps if possible
We see that x^2 + y^2 + 2xy appears in the expression, so we can reasonably conclude that the form is probably (x + y + a)(x + y + b)
Then we multiply out this and figure out what a and b will work
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i need help in funcations grade 11
anyone can help
Okay politoad guy send the question then
Complete the square/ write it in vertex form depending on where you are from
ok
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can someone help me how can i find the expression of the graphique one ?
i mean the first graph
@wide marsh Has your question been resolved?
Well the main thing is that we don't know what the base is.
So if the function has the form $a^x$, can you use the point you have, $(-1,6)$, to solve for the base $a$?
Azyrashacorki
With the point given, we know it should be $f(-1) = a^{-1} =6$. Can you solve for $a$ here?
Azyrashacorki
idk how to solve it
$a^{-1} = \frac{1}{a} = 6$
Azyrashacorki
What about now?
is that going to give me 1/6?
Azyrashacorki
but it aint touching the y in 3 with that
Oh yes mb we should've done that first.
Tu as raison qu'on devrait ajouter un + 2 après, donc la forme générale devrait être $f(x) = a^x +2$.
Maintenant on peut refaire le tout en considérant le point (-1,6) à nouveau.
Ça nous donne $\frac{1}{a} + 2 = 6$
Azyrashacorki
De là tu peux trouver la valeur de a et substituer dans la forme avec laquelle on a débuté
Merde je fais vraiment du n'importe quoi.
Puisque l'asymptote à y=0 est toujours là c'est plutôt un coefficient qu'on doit ajouter au devant.
Du coup, on a $f(x) = b a^x$.
En substituant x=0, on obtient $f0) = b = 3$.
Ensuite on peut réécrire sous la forme $f(x) = 3a^x$ et utiliser ça avec le point (-1,6) pour trouver la base.
Azyrashacorki
Ça devrait marcher cette fois 😅
je t'avoue que je suis perdue je ne sais pas comment le resoudre la
Avec le point on retrouve l'équation $6 = 3\frac{1}{a}$.
Azyrashacorki
je comprends tjrs pas 😅
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How do I calculate the limit as x goes to infinity for sqrt(x^2+x) - sqrt(x^2-x)?
My idea was to factor out x in both and get
Sqrt(x(x+1)) - sqrt(x(x-1))
Then say that we have (x^1/2 * (x+1)^1/2) - x^1/2 * (x-1)^1/2
Then factor out x^1/2 from that and get
X^1/2((x+1)^1/2 - (x-1)^1/2)
But then i kinda get stuck
Multiply with conjugate
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ok so basically, I have a vector whose components are all random picked from a gaussian distribution, (making a sphere of possible vectors i guess), and I am trying to figure out how to stretch this "sphere" along a (normalised) vector. I have tried just multiplying the elements of the random vector by the elements of the stretch direction vector, but that doesn't seem to work, any ideas?
I would guess there is funny linear algebra stuff needed here, but I have way too little experiance to work this out myself
yep
.
every value is possible in gaussian distribution, those that are far from the center are just extremely unlikely
you have a point, but from what I've seen of the code I'm using to generate the guassian, there's definitely limits on it.
there aren't limits
the limits are imposed by computer and time
if you kept it running for a long enough time on a computer that can deal with extremely small probabilities, you would most likely generate any vector
so is this like, a reason I can't change the shape of it? or what?
the shape wouldnt be a sphere
it would be a whole space
well yeah, Im not wanting a sphere
i want it to be like a gaussian, but stretched along a vector
wait
when I said "sphere" i was more meaning like how a gaussian is symmetrical, not that it actally was a sphere
so thats just me being a dingus, sorry about that
you want even get anything like gaussian
all vectors are possible
hence the "shape" of all possible vectors is just the space itself, R^3
ah
on a computer, you cant generate all of them though
you can generate at most finitely many of them
and even if you kept the computer running for eternity, you would only generate countably many of them
while there are uncountably many
i see
i think what Im trying to say is that instead of a gaussian, which is symmetrical or whatever, I'm needing a way to scale that somehow, so that points are more likely along the stretch vector
so you got a normalized vector along which you'll be stretching
yep
say we wanna stretch red along black
firstly we project red into red
so we find the component of red that's parallel to black
then we find the perpendicular component
and decompose red to those 2 components
perpendicular component will be unaffected
parallel component will get multiplied
then add them back
and you get your stretched vector
so how would I do that in 3d? since the parallel's easy enough to find, but how would I get the two perpendicular components?
it's sufficient to find 1 perpendicular
v - p, where p is the projection of v
then p + (v - p) = v
so it will be a correct decomposition
i see
do you know how to do the projection part?
something about dividing dot products by lengths, but it would probably be best if you could tell me
this one is better
projection of a onto v = that
we actually know that |v| = 1
so you can leave that part out
since v is normalized
so it will be (a * v) v in your case
nice, thanks!
np
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I am completely lost for this
which part troubles you?
in the second "lim"
because I don't really see where the sqrt come from in the denom
rafilou2003
Ohhhh true I keep forgetting there's multiple work arounds for these stuff
gotta think outside the box
thanks, I appreciate it
.close
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I get everything until the part where it says "a>2" on the second to last line
Why does it say a>2?
Oh wait nvm
Why is -3a<-3(2)
@real furnace Has your question been resolved?
@real furnace Has your question been resolved?
Multiply both sides by -3 and recall that when you multiply both sides of an inequality by a negative number, you reverse the direction of the inequality sign
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help
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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.
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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
4
imma get a pic of my work brb
is this right?
I think I might have got it wrong earlier because I divided the whole thing by 15 instead of 16
stupid me
i get the same answer as you
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Given the differential equation ( y'' + p(x)y' + q(x)y = f(x) ), which has three solutions ( y_1 = x ), ( y_2 = e^x ), and ( y_3 = e^{-x} ), find the particular solution ( y ) that satisfies the initial conditions ( y(0) = y'(0) = 3 )
riyobi
!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
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6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
1
ok so do you know how to find all the solutions of a linear ODE?
in general
- Find the integrating factor, μ(x), which is given by μ(x) = e^∫P(x)dx.
- Multiply both sides of the ODE by the integrating factor, μ(x), to get μ(x)dy/dx + μ(x)P(x)y = μ(x)Q(x).
- Recognize that the left-hand side is now the derivative of μ(x)y, so we can rewrite the equation as d(μ(x)y)/dx = μ(x)Q(x).
- Integrate both sides with respect to x to get μ(x)y = ∫μ(x)Q(x)dx + C, where C is the constant of integration.
- Finally, divide both sides by μ(x) to get the general solution, y = (1/μ(x))(∫μ(x)Q(x)dx + C).
did you use an AI for that?
Yes, since the steps are a lot so I didn't type myself
ok but
for example
what do you know about the set of solutions of an homogeneous ODE?
for example if f(x) = 0 here
they gave 3 solutions to the equation
but what can you say about the set of solutions of a homogeneous linear ODE?
(part of the answer is in the question)
y1 and y2 are the general solutions of the original equation?
the general solution encompasses ALL possible solutions
I bet that I can create another solution that differs from the 3 we've been given
such as x - e^x + e^(-x)
not really no
c1 and c2 can't be any real number
and that doesn't yield all solutions
let's just forget about y1,y2 and y3
and focus on this for now
the solutions to the homogeneous equation are y1 y2 y3
ok so
solutions of y'' + p(x)y' + q(x)y = f(x) are just solutions of the original ODE
solutions of y'' + p(x)y' + q(x)y = 0 are solutions of the homogeneous ODE
Ooh
what do you know about the **space ** of solutions to a linear homogeneous ODE?
Iirc : [ y(x) = c_1y_1(x) + c_2y_2(x) + \ldots + c_ny_n(x) ]
riyobi
so for a homogeneous ODE
you can just add linear combinations of the solutions you find
and get another solution
sounds like a vector space
Yes
to find the general solutions
all we have to do is pick 1 solution
we call it y_p
(p for particular)
and then
all the other solutions are given by
$y_c = y_p + y_h$
rafilou2003
(h stands for homogeneous)
Yes
welp
we already have one particular solution
(x for example)
we just need the homogeneous solutions
to do that... what happens when we subtract y_1 to y_2 for example
well both of them verify y'' + p(x)y' + q(x)y = f(x)
so y_1 - y_2 is gonna verify
y'' + p(x)y' + q(x)y = ... 0
we have a first homogeneous solution
since this is a 2nd order ODE
we only need 2 independent ones
and then we have our homogeneous solution space
to get a second one
well y_1 - y_3 for example
same thing
so $y_h = c_1(x-e^x) + c_2(x-e^{-x})$
rafilou2003
we add our particular solution in the bunch and...
$y_c = x + c_1(x-e^x) + c_2(x-e^{-x})$
rafilou2003
got it?
yes
Then we need to write down other cases when the particular solution is the other two?(e^x or e^-x i mean
Ohh ok
Darn my internet delayed so bad
But then what to do the next ?
Plug it in?
( y'' + p(x)y' + q(x)x + q(x)(c_1(x-e^x) + c_2(x-e^{-x})) = f(x) )
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i assume this should say g'(x) never equals 0 rather than g'(x) ≠ 0
Aren't both expressions basically the same?
@untold arrow Has your question been resolved?
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@untold arrow Has your question been resolved?
@untold arrow this is a wild one and took me a while
but check this out
Notice that the statement $g'(x) \neq 0$ means that g must be strictly monotonic (Darboux's theorem). I will attempt to prove this by contradiction, first suppose that such $\xi$ doesn't exist.
then $f'(x) \neq 0$ as well making f(x) monotonic. then for $\int_a^b f(x)dx = 0$ to be true there must exist a unique $c \in (a,b)$ such that $f(c) = 0$. Now observe this equivalence:
[
\int_a^b f(x)dx = 0 \leftrightarrow \int_a^c |f(x)| dx = \int_c^b |f(x)|dx
]
which is true because f(x) has the same polarity before c and opposite polarity after c.
Now define $u(x) = \alpha + \beta g(x)$, such that $\beta >0$, and $\alpha,; \beta$ are chosen to make $u(x) > 0, ; u(c) = 1$ then depending on the type of monotonicity you would have either
[
\int_a^c |f(x)g(x)| dx < \int_a^c |f(x)| dx = \int_c^b |f(x)|dx < \int_c^b |f(x)g(x)|dx
]
If $g(x)$ was monotonically increasing, and
[
\int_a^c |f(x)g(x)| dx > \int_a^c |f(x)| dx = \int_c^b |f(x)|dx > \int_c^b |f(x)g(x)|dx
]
If it was monotonically decreasing, and since $u(x)$ is positive then $f(x)g(x)$ has the same polarity before c and opposite polarity after c. hence
[
\int_a^b f(x)u(x) dx \neq 0
]
but if that's the case then
[
\int_a^b f(x)g(x) dx = -\frac{\alpha}{\beta}\int_a^b f(x) dx +\frac{1}{\beta}\int_a^b f(x)u(x) dx = \frac{1}{\beta}\int_a^b f(x)u(x) dx \neq 0
]
thus finishing the proof by contradiction.
Mohamed Mohsen
honestly, with these type of questions, I don't even know what hint to give.
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i solved it already but it says that i cant directly use manipulation to solve here
Please don't occupy multiple help channels.
using x = 1/t
Wdym by direct manipulation?
write it as 1/y-ln(1+y)/y.1/y
comes out to be 0
Did u try standard limits
Divide and multiply the expression by 1/x
U will get x - x(log(1+1/x) /1/x
So you will get x - x = 0
Since log(1+x) / x where x tends to zero = 1
no i did it using substitution
i got right answer
but it was written in remarks that that method will give wrong answer
so i wanna know why so
it won't
Rather it shouldn't
What the actual answer
it is written clearly
in my book
that it will give wrong answer and it illustrates it too
clearly gives 0
But we can't think of a flaw in their argument too
must be something complicated

Try taking the remainder of Taylor expansion
?
The n+1 fold integral try taking it for 3rd term
i dont know what it is tbh
not that good at math 😭
i mean i know some integration but i dont know what fold is
Have u studied taylors theorem?
nope just know taylor series expansions
Ahh k then leave it
It's complicated tbh
Still don't know where that 1/2 came from
Plot it on desmos
Limit does not exist
Yea i can see how they got 1/2 I'm saying I don't understand how 1/2 has any significance on the graph

red is y = x - x^2 ln(1 + x)
blue is y = 1/2
Can't send a pic cause it isn't loading
yea so limit dosent exist
how
Why does 1/2 have any significance
thats the horizontal asymptote of x - x^2 ln(1 + x)
It approaches infinity from one side and zero from the other
Ohh wait fck

jfc
Nvm sry sry I'm high
Then why do we get zero by standard limits
How
Possible taking into account I'm high 
U do it
can you walk through your thinking in saying that this limit is 0 instead of indeterminate
Take the standard limit ln(1+x) /x is 1
We get lim(1/y) - lim(standard limit) ×lim(1/y)
Which both cancel out to get 0
yea AI's correct
yea i get it
you cant just apply one limit and then not the rest
lol
once you apply that limit in the middle, you get (undefined) - 1 * (undefined)
limits are applied from the outside in, not the inside out
Ohh wait

Fck
after I reremember ln(1+x), I do have the way to solve this problem using taylor series
huh?
its this, right?
yea
nice
Yea if u take till n dont forget to add the remainder
Yea that's what the book has done
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hmm, if I have a Hausdorff space X, can removing a point from it remove its Hausdorff property?
say, if X = S^1, and I delete one point... does the modified circle remain Hausdorff?
yes
hm... so it's true in general?
if X is Hausdorff, then X \ {p} is Hausdorff, where p \in X?
yes, i think so

(i forget if the empty space is Hausdorff)
it is a fact that subspaces of a hausdorff space are themselves hausdorff
mhm
ah, right
hmm
it is
then yeah
you remember how I wanted to show that the wedge sum of Hausdorff spaces was Hausdorff?
I think I can break it into a few cases 
if if x and y are in the same Hausdorff space, then we're done by assumption
if x is in X_a but y is in X_b, then we can take the open subsets to be X_a and X_b \ {p_b}, where {p_b} is the base point for X_b...
I think?
X_a isn't open in the wedge sum though
ah, it's not? 
no, because its preimage in the disjoint union is X_a and then a single point in each of the other spaces
this is not in general open
okay then let's just take X_a \ {p_a} then
now...
one more case
if either x or y is a base point...
WLOG, assume it's x
in this case... what should we do? 
the open nbhd of y can stay as X_b \ {p_b}
but what about the open nbhd of x? 
hmm
ok so it’s like
if you use the universal property of the wedge sum
then open subsets correspond to picking an open subset in each space, such that either all of them contain the basepoint, or none of them do
maybe this will help
hmm
in other words the open sets containing the base point are precisely those that are open in each space you've wedged, separately
you can figure this out by considering the continuous maps from the wedge sum to the sierspinski space
sierpinski is not a word I was expecting to come up in this discussion
the sierpsinski space is the classifying space for open subsets
yes but still
and then the universal property of the wedge sum lets you figure out what continuous maps out of the wedge sum are
okay, I'm back
so I need to pick an open nbhd of x that's disjoint with X_b \ {p_b}

that’s gonna be hard if x is in X_b lol
(x is in X_b in this case)
.
ok how exactly are you done
well, if x and y are both in X_a, then we can find open nbhds U and V around x and y st U \cap V = \emptyset, since X_a is Hausdorff, no? 
this doesn't work?
U, V open in X_a yes,
oh.
but you need it to be open in the wedge sum
.
that’s what open subsets in the wedge sum look like
so you’ll be in trouble if U or V contain the basepoint
there must be some way to remove the base point then 
(unless x or y are the basepoint)
mhm, but then you have to modify your open subset to make sure it’s actually open in the wedge sum
well yes, but I am dealing with that case separately 
or does it make more sense to do it together?
instead of breaking this into so many cases?
maybe try understanding this first
it’s gonna be hard to prove the wedge sum is Hausdorff if you don’t know what open subsets in it look like
the open subsets of the wedge?
yes
hm
it makes some sense with the geometric picture
and/or you can use the universal property
okay let's wedge 2 circles
this is the case we showed earlier, when x and y belong to different spaces and neither is the basepoint
mhm
.
yes, but visually 
i mean, if you know how to pick open subsets in the circle visually…
they’re unions of open balls
is this an open subset of the wedge?
yes
you’ve picked an open subset from both circles
one is nonempty, and one is empty
and neither contains the basepoint
why does an open subset in the wedge need to contain stuff from both spaces?
I don't think I understand why 
.
that's not what I meant
hmm, hold on
you’ve picked a nonempty subset of the top circle
and an empty subset of the bottom circle
both are open
and both do not contain the basepoint
nvm I answered my own question lol
I was thinking of it the wrong way
okay wait, if it does contain the base point, then what happens?
if any of the open subsets you pick contain the basepoint, then all of them have to
what if some of them don't?
then it won’t be open in the wedge
yes that’s open
you’ve picked nonempty open subsets of both the bottom and top circles
and both contain the basepoint
otherwise I’m confused at your drawing
you've drawn the lines too big and are hiding what I think you're trying to show
what subset of the top circle have you picked?
the top circle contains the base point
you meant this? (with the top bit there as well)
so the subset of the top circle you’ve picked is only the base point?
is this open though? what ball around the wedge point is entirely in the open set?
wdym only the base point?
none 
i am asking you what subset of the top circle you are picking
let me colour it
ok then this fails to be open in the wedge
yes, but I wanted to ask why
the red set seems to be open in the top circle, and contains the basepoint
the blue set is open in the bottom circle, and does not contain the basepoint
I get that
so it fails the condition i laid out
but why does this mean it's not open?
in this case the wedge sum is metrizable
and no open ball around the wedge point is entirely in the open set you've chosen
but I don't see why the condition is tied to the openness of the set 
so you can also think in terms of open balls
so you can use the definition of the quotient topology
that makes sense
and/or the universal property
so it's not open by definition, because in this case the drawing with metric is the wedge sum (up to homeomorphism)
yes, though i guess you’d have to prove that
the topology on the wedge sum is a quotient topology
so for U in the wedge to be open, we need q^-1(U) to be open?
the topology on this drawing comes from it being a subspace of R^2
yes, that’s the definition
though I slightly prefer this
if U is the union between the red and blue parts I drew earlier, which part becomes not open under the preimage 
the preimage is not open
in the disjoint union topology
the red includes the wedge point, so in the preimage you have a single point in the bottom circle
right...
yes, and that together with the other set in the bottom circle is not an open subset of the bottom circle
wha
so it’s not open in the disjoint union topology
why's the blue part not open in the bottom circle? 
that’s not what I said, higher
oh huh
i said that the blue part plus the basepoint is not open in the bottom circle
so the preimage fails to be open in the disjoint union topology
right, okay
quotient topologies can be hard to grasp
yeah
this is why I really think you should try to understand the universal property
I don't yet know the universal property for quotients (though I know you wrote stuff about it in my thread)
I guess 
but I do want to do this exercise without that property too
I'm pretty sure Lee "intended" me to do it w/o universal properties
an alternative to the universal property is through saturated sets
sure
i don’t necessarily agree with that but that’s ok
I should probably mention that I don't yet know what those are either 
I know they're coming up though
the wedge sum of two circles is metrizable
so you can use metric space intuition to help
well, I'm supposed to prove this for general topological spaces...
"intuition to help"
that doesn’t mean you’re not allowed to use metric space intuition
ah, true
it is very useful for lots of topology problems
most topologists only think about R^2
like your first instinct should really be to draw a picture
not work with the symbols
if you try to approach topology the same way you’d approach, like, algebra
you won’t have a fun time
I have a few pictures I suppose
I'm trying to figure out what open nbhds to take though
oh hold on
I can choose X_a \ {p_a, y} to be the open nbhd of x, and X_a \ {p_a, x} to be the open nhbd of y, yeah?
@atomic forum @dusty ice
yep
mhm
these intersect in general?
oh uhh
oh yeah true, so you’d have to worry about that
you should know that compact subsets of Hausdorff spaces are closed
in particular finite subsets are always closed
okay hold on
we know that X_a is Hausdorff, so we can choose open nbhds U and V that are disjoint in X_a
mhm
then... can I remove p_a from each of these sets and call it a day, or is it possible I lose the openness of U and V when I do so? 
well, how would you check whether U \ {p_a} is open?
well, its preimage is going to be entirely contained in X_a, since it doesn't have the base point
i mean open in X_a
oh
well, we need to find an open nbhd around each point in U \ {p_a}
that's contained in U \ {p_a}, that is

okay, I'll come back to this case later...
in the case where x is a base point and y is anything else, we have smth like this
can I just take X_a (the top circle) to be the open nbhd of x, and X_b \ {p_b} (bottom circle minus base point) to be the open nbhd of y?
they're disjoint, and if I haven't made a mistake, they should be open in the wedge also?
I'll be back in 15 min
X_a won’t be open in the wedge sum
because what you’re doing is choosing X_a from the top circle and the empty set from the bottom circle
these are both open in their respective spaces, but one contains the basepoint and the other does not, so it won’t be open in the wedge sum
@tawny nacelle Has your question been resolved?
I see
then could I pick X_a \cup {p_b} to be the open nbhd of x?
oh, but {p_b} isn't open in X_b, is it?
hm
okay wait, since X_b is Hausdorff, we can separate p_b and y with open sets U and V
then take X_a \cup U to be the open nbhd of x 
and V to be the open nbhd of y
these are disjoint, X_a \cup U is open in the wedge since they contain the base points, and V is open in the wedge cause neither it nor the empty set contain the base points
Yep!
You’re getting the hang of it
Those are the same point in the wedge
oh no
yes, you are right
I agree
so now I only have to deal with x,y in X_a, and neither is a base point
The only case you’ve left out is when x and y are in the same space, but neither is the basepoint
Yeah
I feel like U \ {p_a} and V \ {p_a} should work, but I am not 100% confident
well, let's see
these are obviously disjoint cause U and V are disjoint
U \ {p_a} should be open in the wedge cause neither it nor the empty set contain their base points
and likewise with V \ {p_a}
this surely works... yeah?
Why is U\ {p_a} open in X_a?
hm, good point
Once you’ve got that i think you’re done
well, not exactly, right? 
Isn’t this the last case
yes, but shouldn't I prove that a subset of the wedge is open iff either its intersection with each X_a contains X_a's basepoint, or it doesn't?
Oh you mean - prove the condition i stated
yes
Sure yeah
Ig i used the universal property to deduce that condition, but you’d have to prove it
okay, I've got some work to do then 
And/or you can just check that all the subsets you use are open by directly using the def of quotient topology
ah, true
I've got to go have dinner soon, but I'll try to first prove this when I come back
There’s a nice way to do this for arbitrary quotient topologies btw
before the condition thing
Open subsets of X/ R correspond to open subsets of X which are closed under R
So you require that if x in U and x R y, then y in U
ic
okay, I'll be back in a bit
thank you for all the help Pseudo (and Edward, if you're still here)! 
im here though im gonna head to sleep soon
@tawny nacelle Has your question been resolved?
@tawny nacelle Has your question been resolved?
YIPPEEE
@tawny nacelle what’s the actual question
like is it this?
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is this correct
.close
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Still unable to get used to how exactly u-sub works and how to make a decision on what to set u too
U set the variable 'u' to that part whose differential is already sitting in the expression
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Aftab tells his daughter, “Seven years ago, I was seven times as old as you were then. Also, three years from now, I shall be three times as old as you will be.” (Isn’t this interesting?) Represent this situation algebraically and graphically.
let Aftab's age and his daughters age be some variable, like x and y
try to make the first statement, then the second statement
thanks
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why is this function correct for constant x0, k, j
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for $j \leq k$, you get
[((x-x_0)^k)^{(j)} = (k \cdot (k-1)\cdots (k-(j+1)))(x-x_0)^{k-j}]
and evaluating at $x = x_0$ gives $0$.
for $j = k$, the above formula gives $k!$, so taking any further derivatives will give 0.
Tushar
✅
hi
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how many sheets of metal that are 500mm x 1000mm can fit in there and can you show calculations
the little pipe doesnt matter
@misty owl Has your question been resolved?
<@&286206848099549185>
So can u send the question again?
how many sheets of metal that have measurements of 500mm x 1000mm can fit with this image
What is that don’t break thing ?
okay
so can u find the area of the image first by using the lengths that are given in the image??
u need help with that?
im pretty sure its 12.3 x 3 = 37.8m^2
do u know how to convert
divide by 1000
first convert them
convert what?
12300mm x 3000mm = 36,900,000mm^2
the sides
very good and what will u get after converting it?
12300 mm x 3000mm
very good
= 36,900,000mm^2
so now, do u know to calculate sheets now?
basically u have the area of the image,right, now ujust need to divide it by the area of sheet, then it will give me thenumber of sheets
so 36,900,000mm^2 / 500,000mm^2?
73.8
yes
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hi
there is a icosceles trapezium ABCD
AB = a, CD = b , a>b
AB is perpendicular to CD
the diagonals AC and BD meet at point O
if angle BAD is alpha and angle BOC is beta
prove that
tan(beta/2) = a-b / a+b tanalpha
i would really apreciate some help
Im onto nothing
<@&286206848099549185>
hey sorry for being annyoign but is anyone there? please
In process of solving
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.reopen
✅
okay brother imw aiting here
??
this is a mathematics server.
he was member since jan
That was the first time he'd posted lol
back to the question
@lethal bison Has your question been resolved?
my bad it should be
oh nvm it's obvious i got it all
u wanna hear my solution
or just some hints
oh you guys have 2 russian names so I got confused XD
I saw that you worked out the right side
now we need to work out the beta/2
180 - beta may help you
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how to do
,rotate
i got t=8 but that doesn’t sound right
,w minimize sqrt((t/2-1)^2 + (t/2-3)^2)
I think that's what you're looking for, you've just gone wrong with the working somewhere
@velvet cove Has your question been resolved?
You might as well drop the sqrt to make things a bit easier for yourself too
i dont get it pls explain
i mean i undertand what u said but idk how i can implement it
let's open another channel this one is occupied
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How do I solve what I marked?
let u = 2+r might work
u = 2+r
r = u-2
$$\int \sqrt u (u-2) du$$
JustToPro
u can multiply sqrtu with both terms and then power rule
(dont forget to change bounds unless if u are going to convert back into r)
u = 2+r
du/dr = d/dr(2+r)
du/dr = 0 + 1
du/dr = 1
du = dr
du/dr = d/dr(2+r)
i didn't understand this line
differentiate both sides with respect to r
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Hey, so I’m working with GL(n,F) in an intro course for group theory. How does one go about proving closure and associative of matrix multiplication in this group? Any advice?
i am in eight💀
,rccw
can u help ?
notice that $b^{1/2} = \sqrt{b}$
my eight standard brain is bursting
artemetra
wait can u explain me how it is possible
hmmmm ok
in general $b^{1/n} = \sqrt[n]{b}$
artemetra
that means a is also the same right?
yep
hmmmmm
do you know how to proceed?
are u good in area and perimeter?
yes'
great
a swimming pool is surrounded by a concrete path 4m wide if the area of the concrete path surrounded by the pool is 11/25 that of the pool find the radius of the pool
hmmmm
yes
great
and thatis 11/25
yes that only
what's the formula for the area of a circle?
227/7 multiplied by r square
okay i'll write pi for simplicity
ok
we have that $\pi r^2 =$ area of the pool
artemetra
and $\pi(r+4)^2 =$ area of the pool and path
artemetra
hmm
thus, $\pi(r+4)^2 - \pi r^2$ is the area of the path
artemetra
does that make sense?
hmmm yes
so
we can short out pie
artemetra
that's your equation where you need to solve for r
indeed
but why divide ?
because
the area of the concrete path surrounded by the pool is 11/25 that of the pool
ok'
it simplifies to $\frac{(r+4)^2 - r^2}{r^2} = \frac{11}{25}$
artemetra
can you take it from here?
yes
awesome
Thank u very much
no problem
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Ex 14 compare the 2 numbers
You could put everything in 2 underroot and then compare
can you show me an image or write how would it look? If u may ?
I am not home rn but wait a sec I think there somethin on google
I'll do for first one
But I won't write the first under root
Wait
I didn't see the + sign
No problems
,rccw
Couldn't find an attached image in the last 10 messages.
Like if one is bigger or smaller than another or if they are equal
,rccw
You can square both sides
Get rid on one square root
And then ?
Then just put value of ✓6 and✓7
Is it possible without aproximating ?
Wait let me think
You can subtract 6 from both sides
Then u get 5+4✓6 and 5✓7
From there you know 1st num is bigger
Yeah, ok Thank You Very Much )
Yw
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okay guys i know its like third time i ask for nearly the same thing, but im close to fully getting it again. tho i like to ask how to figure this one our, the 1, in the middle is kinda confusing me
Rewrite as an irreducible fraction.)
what grade are you in
Simplify the top
First write division in another term
Wouldn't it be simpler if you rewrite division as another term first?
bro i forgot how to fix these tupe of questions
Either way works 🙂
Ig that's true
so 3/12
real
as another term??
So that's ((3/12)/(1/(3/8)))
@twin horizon
Can u explain i gtg
aaah, okay
Have you learned indices
Like powers and exponents
@vast shale
ehm
That's not the final answer
yeah so
like this?? then wwhat?
or wait, u want me to write it sideways??
It turns to (3/12)÷(3/8)^-1
Do you understand this
Yes but express it as a fraction
x^-something=1/(x^something)
so how do i type it?
yeah perhabs.
