#help-23
1 messages · Page 209 of 1
it will be in the end
like imagine F(x) is the antiderivative of the integrand, all it's actually asking is lim[a->inf] F(a+1)-F(a)
do you see what im saying
^
Yes, if you were analyzing this with trig substitutions
I don't even know what that is
I really am not supposed to even know how to solve that integral
1/sqrt(a^2 + x^2) is a trig substitution that relies on the Pythagorean Theorem to sub in known ratios, similar to u-substitutions
But yeah, that's kinda beyond the scope of this question
a^2 in this case would be 1, since 1^2 = 1
But we're getting off the rails here
can you outline the suggested method again
yeah you substitude x=atan(u) right?
that one about inequalities
I am familiar with that but am not supposed to know it
anyway
pfft.. you can know it.. but you might not be allowed to use it to solve the problem 😉
so essentially you have to find some sort of inequality from the function inside the integral
like, if the function was 3sin(x), then it is true that -3<-3sin(x)<=3
then you can integrate each part of the inequality
and you find something
so squeeze theorem in essense ig
not really, you can find anything
it will just be (number) <= integral <= (other number)
but
if lim(number) <= lim(integral) and lim(number) = infinity
then lim(integral) = infinity too
is that too confusing?
wish I could draw here or something
The answer is just the integral itself
well we know that the function is greater than 1 for all x>0
a is part of the integral
Where?
here
Right, but where is that in the function
a can do whatever it wants
how does x change in relation?
We're not told
it doesn't have to change, but what changes is the end result, because the integral, like smork said is equal to F(a+1)-F(a) with F being the antiderivative
the integral is a number after all
it can't be a function
right, by definition the integral is the difference of 2 functions of a
so a is definitely a part of the integral
I mean the limit here is obviously equal to infinity
I just havee to find a way to show that
rly, i graphed it and it seems to be 1
probably squeeze theorem yeah
ok so the original function is greater or equal to 1?
is it lesser or equal to something else?
that would probably solve it
are you allowed to differentiate?
yeah I am going to test something like that to find the extremums
i was gonna say that yeah
I could very well be wholly off base... but if a + 3 = 10, how does that prove that x = 12?
check my work it should be less than equal to sqrt(2)
yeah seems to be right
one moment I will try something
wait what
ah I don't know
I can ask my teacher next time at the end of the day
I will close now because I got tired and this is one exercise from the 20 more I got to do
thanks for helping
.close
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Has there been discovered a way to assign a numerical value to the asymptotic growth of functions?
Such that the growth value of any exponential function is larger than the growth value of any polynomial
meaning we could compare the absolute growth values of two arbitrary functions and declare which grows faster
and thereby also essentially plot all possible 1D functions on a scale according to their growth
that would only be applicable for polynomials
Got an example of what you're trying to describe?
Because... when it comes down to it.. it sounds like you're describing the limit of a fraction, where the numerator and denominator have different degrees
not just degrees, I refer to arbitrary functions
the capability of assigning an arbitrary function a numerical value regarding its growth
But you have to have some function in mind to include in the comparison
not as a necessity
That's... the degree of the function
isn't it?
we could declare the function f(x) = x a growth value of 1
ax^4 + something has an ultimate growth rate of x^4
and then assign all other growth values relative to it, but does that growth function exist?
As said before only works for the specific case of polynomials
Which is why I'm curious about an example you might have in mind
i.e., where would that not be the case
any arbitrary other function?
f(x) = x!
thinking
f(x) = ln(sin(floor(x^cos(x))))
whatever, polynomial comparisons are trivial of course
ehh.. sin and cos should be right out... they're oscillating functions, going up to a max, going down to a min, and repeating
They don't grow infinitely
it was a sample
regardless, I'm not certain whether a growth assigning function exists
Well, it's always relative to another function
hence the limit of a fraction where the numerator and denominator grow at different rates
The relativity of such a function wouldn't be an issue as said
since we can declare the value of any function to be 1
which would infer the values of all other growths
Then the value would be 1, and it wouldn't grow at all
The growth value is 1, not the function itself
Try graphing what you're talking about
See if the visual cues help?
Because if y = 1, then you get a horizontal line with no slope
I don't think visualisations would help :/
Well, you're talking about the overall slope of a function, but the slope changes depending on the x value you're looking at
That's... the whole point of derivatives
which is, by definition, the rate of change in y compared to the rate of change in x
which would declare the function f:R->R; f:x|->1 to have a growth value of 0 for instance
so.. again.. by definition it's going to be relative
which is not an issue
why
Because you can't isolate the slope of a function above degree=1
once you hit a degree of 2, the slope varies constantly
we can categorize asymptotically, e.g.
f element Theta(n)
f element Theta(logn)
why wouldn't we be able to assign such sets a numerical value relative to each other
I've been saying it's all relative from one function to another the whole time, and you've disagreed with me
So
I appreciate the help, but why are you talking about slopes :D
Because slope is the rate of change
It is the growth rate
I seek a way to numerically measure asymptotic growth, not compare the slopes of polynomials
Define asymptotic growth
I don't know what you're talking about
a rate is one value compared to another.. y/x
that is slope
if the correlation between growth rate and slope is lost on you... I don't know where else to go
in relative notion a function f grows faster asymptotically towards ->inf than g if there exists a c>0 such that from a x0 onwards (x≥x0) the inequation f(x)≥g(x) holds
np, it's an analysis 1 topic 🦆
I'd rather not have a guess
Could be me not understanding exactly what's being asked, since I don't have a way to visualize what you're asking
Could be me just... being right, since growth rates depend on the x-value of a given function
and since x values are variable, growth rates are subsequently variable
it's fine if you aren't yet familiar with the topic, but thanks for the attempt :)
hence, the overall (average?) growth rate might be undefined
mm... thanks 😉
anywho... have fun finding Jimmy Hoffa!
(no seriously... let me know if you find an answer)
(would be SO helpful with evaluating limits.... )
Has there been discovered a way to assign a numerical value to the asymptotic growth of functions?
Such that the growth value of any exponential function is larger than the growth value of any polynomial
meaning we could compare the absolute growth values of two arbitrary functions and declare which grows faster
and thereby also essentially plot all possible 1D functions on a scale according to their growth
Are you asking if there is an injective mapping from equivalence classes over asymptotic growth to real numbers?
hm if the growth comparison implies injectivity then yes
from equivalence classes to real numbers yes, injective
I would very much assume there is, theoretically at least… though I doubt it is practical
hm it'd be quite intriguing as we could essentially map out all growths we have discovered so far and fairly quickly determine which functions grow faster than others
But if [x^r] represents a unique equivalence class for every unique r in R, then is such a system really useful?
hm I'd argue it could be
I stumbled upon it during Theoretical Comp Sci
eg if we were to assign the basic linear function f:R->R, f(x)=x the value 1
and all growths above constant to be ≥0
then all logarithmic functions must be between 0 and 1
yet only occupy a small enough space
In fact arbitrarily small
to leave room for infinitely many other slower and faster growing functions
with values between 0 and 1
the realization of that principle is probably where it might collapse
but not sure
The problem seems to be that we can’t define it intuitively, because mapping [x^r] to r for example makes it impossible to make the mapping injective
I suppose we could prove the existence of an injective mapping by proving that the cardinality of the domain is equal to the cardinality of the set of real numbers
hm then potentially instead onto a different set with higher cardinality yet also an ordering?
Kinda like a mapping to itself? 🙂
I think the main problem with the numeric approach is that it seems more difficult to figure out the numeric value that it is to just compare the growth of the two functions
It’s much easier to prove that 2^x grows faster than x^2 than it is to define a mapping that meets the criteria and then figure out what the values assigned to 2^x and x^2 are
My younger brother sits next to me and asked why can't we measure which function reaches infinity first and measure the distance :]
yeah, I think I'll resign to it for now
lol that’s sweet
thx
Even if we find the numeric values they’re likely given by limits, and comparing those limits will be the same as comparing the original functions
If you find something practical let us know, maybe it’ll make you rich 🙂
It was a pleasure
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And then break everything apart?
The fraction?
Oh wait
No
Ill just get to the same thinf
not everything
but breaking apart the fraction somehow
will help after you rewrite that way
okay you made a sign mistake
$$\frac{e^x-1}{xe^x+1}=\frac{(xe^x+1)+e^x-1-(xe^x+1)}{xe^x+1}=\frac{(xe^x+1)+e^x-1}{xe^x+1}-\frac{xe^x+1}{xe^x+1}$$
Austin
Ohhhh so I do it that way
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i found the product
but idk how to solve
do i need to use an identity to solve cos 3x=0
so pi/6
and doesnt cos 270 =0
so cos 6pi/4
so my answer is 6pi/4 pi/2 and pi/6
is that right
wait do cos 5pi over 6 work
when subbed into cos 3x
ok ty
whats k
ohh i get it now
tysm
.close
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i need help with what to do to find the third vector

i found the first and second eigenvector, but i dont know how to find the third one
i know the eigenvalue -1 has multiplicity two
then how would i find the general solution then
each eigenspace would be the span of your eigenvectors
their union is the set of solutions
you could express those algebraically
(a,-a,a) is one general solution for the -1 value
it has to be in the form C1e^At + C2e^At+…
i have that
this is the solution
i dont know where the second term comes from
interesting, ive never seen this form before
its #17 bte
btw
if an eigenvector has a multiplicity higher than 1, then the generalized eigen vector is (A-lambda*I)^m * a vector u = 0
it has multiplicity 2
when i row reduced i got two free variables
im confused on what to do after
im truly not sure, im not familiar with this sorry
do i @ the helpers then?
Sure
<@&286206848099549185>
so i can ping every 15 minutes?
yep
can it be whatever i want?
does replying count as pinging then?
Nope
<@&286206848099549185>
@hard thistle Has your question been resolved?
<@&286206848099549185>
@hard thistle Has your question been resolved?
<@&286206848099549185>
<@&286206848099549185>
No way, no one comes here
@hard thistle Has your question been resolved?
<@&286206848099549185>
<@&286206848099549185>
?
i need help finding the eigenvectors of a matrix whos eigenvalues is of multiplicity greater than 1
^
im sorry thats too advanced for me
<@&286206848099549185>
@hard thistle Has your question been resolved?
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What…5 hours
5
@hard thistle Has your question been resolved?
Dude, what's your doubt in this ?
@hard thistle
The question seems answering itself.
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Hi. I’m struggling to figure the question out “What conclusion can you make from this table?” I haven’t done this before this year so I’m new to trigonometry and I really don’t want to lose any marks.
<@&286206848099549185>
The ratio of the sides is dependent on said angle
These are the angles that they gave
So would it be All ratios are the same?
.close
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You can see in your table they are of samr value
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Are you having trouble with 7?
I am hoping anyone can maybe help me check my work , confirm if I have done a correct job on 5 & 6
Oh, have you tried wolframalpha... not sure it'll do it, but worth a shot?
give me a sec
But that might not be obvious
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where did i go wrong
im new to partial derivatives
check with online calculator
now im confused
also i dont know what the fz(1, 1, 1) notation means
is that just in respect to z, then plugging in values 1, 1, 1
derivative with respect to z at point (1, 1, 1)
i dont see an issue on the first part, other than the notation
on the bottom left you're not differentiating f with respect to x, you're differentiating the differentiate of f
oh shoot
ur right
how do i denote this
LordFelix
but there's many ways to write it
(replace d with delta, it's just very annoying to write that on discord)
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Yuh
I have these equations
And im uspposed to do this
i can translate it real qucik
Investigate whether there is a value for a such that the line with the equation y=2x-54 is tangent to the graph G at the point P(6/f(6)).
And i really dont know what im supposed to do yk
i just thought of someting
i would try to get the tangential equation of P x=6 and see how it is attached to a
So now i put 6 into fa(6) so i got 174-18a
and now i try to get the gradient of 6
and then assemble a tangential function
daimn my approach turned out to be fully right and i got it without help
wo
w
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please help, when solving recurrence relations like a_n = 3a_(n-1) - 5a_(n-2), i know to solve this we have to first make a characteristic equation for it and then we have to factor out the least n term like n-1 or in this case n-2 and after that we get r^n -3^n-1 + 5r^n-2 = 0 =>> r^2 - 3n + 5 = 0 and then so on, but i want to ask what if we have a_n = 2a_n-1 + 2n^2 how do i factor out n-1 from this?
@modest owl Has your question been resolved?
<@&286206848099549185>
please do
sure thing dude
let me just solve the equation
and then i can help
for the given recurrence relation you can approach it by using the method of undetermined coefficients to find a particular solution. the form of the particular solution will be a polynomial of the same degree as the non-homogeneous term, which is 2n^2
assuming a particular solution of the form p(n)= An^2 + Bn + C, substitute this into the recurrence relation:
[ a_n = 2a_{n-1} + 2n^2 ]
Rick
[ An^2 + Bn + C = 2(A(n-1)^2 + B(n-1) + C) + 2n^2 ]
Rick
after simplifying you can solve for the coefficients a, b, and c. once you have the particular solution, add it to the solution of the homogeneous part of the recurrence relation to get the general solution
hopefully that can help you solve the question better
if its an arithmetic series you can write a_n-1 as a_n - r
i am trying to solv it this way:
a_n = 2a_(n-1) + 2n^2
r^n - 2r^(n-1) - 2n^2 = 0
where do i go from here?
@tough sigil
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@exotic charm Has your question been resolved?
<@&286206848099549185>
Hello
I think $f_x(x,y)$ is the derivative with respect to x. Then you put x =0. Then you differentiate wrt t.
Solomaniac
That should give you $f_{xy}(0,t)$. Put t=0
Solomaniac
i did this and got -1
Is it incorrect ?
idk if it's incorrect but im not sure what to do from there
like when u sub x = 0 u get -y
sub y = t to get -t
differentiate wrt t gives -1
no clue what to do from there
i dont get how differentiating wrt t gives me fxy
is what im asking
t and y play the same role in f
why
it's just the dummy variable of the second argument of f
f(x, y), f(a, b), f(c, d) are all the same things if x=a=c and y=b=d
i get that but like
when you find fxy dont you have to differentiate the whole partial derivative of x with respect to y
here they are subbing x = 0 and then differentiating it with respect to y?
@plucky elk
What is "here"
in that example
i dont get why subbing x = 0 gives me fxy
normally when u do fxy u differentiate the whole of fx with respect to y?
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it has been longer than 15 mins
<@&286206848099549185> plsss
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I solved this karnaugh map, and compared it to a KMap calculator online
is my solution less correct than theirs, or entirely invalid?
sorry if this isn't the right place for this... I couldn't find a good fit for it in computer science servers either.
@devout steeple
your solution is also correct
but KMap is more simple than your expression
you must add several block as possible as big
your method is 2 2 4
KMap is 2 4 4
ohhhh i see what you are saying
i need to make the purple group include the cells above it
thank you!
you are welcome
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1 and 2. I understand the concept but I don’t know where to start lol
find p(x) by multiplyng x+2 and 3x^2 + x + 3 and add 2
a = bq + r
for 2 use remainder theorem
is this for one?
assume the pollynomial is f(x) find f(-2) and equate to -7
yea
yea
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can someone please help with me with question 83
@lean otter Has your question been resolved?
fuck no
is that because u is a function
a function of x yes
so the derivative of a constant x a function is just the constant times a function
u is defined as g(x) = ...
so it should be pi/10 u'
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Is there a quick way (without computer) to compute $8^8 (\mod 9)$?
WhoTao
yes!
8^2 is 1 mod 9
right. So then (8^2)^4 = 8^2 = 1 mod 9
yes
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hii rly struggling here
the new angle a measurement should be 143
but that gives me the same angle measurement as c1
which like. shouldn’t be the answer
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@jolly pasture Has your question been resolved?
question got cut off
just had to find an SSA triangle
i got it though
thanks
.close
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can someone explain to me why
the range is [0, infinite)
how they got it thank you
no
Can the square root of something be 0?
im not sure
sqrt(0) = ?
0
so, yes the square root of 0 can be 0
Now more specifically, if f(x)=sqrt(2x-6)
Can 2x-6=0 ?
x=3\
Alright
so far we've shown the range cannot include anything negative
and does include 0
Now we want to know, does it go alll the way to infinity?
What do you think about that
yes because its not -
What do you mean by that?
infinity numbers are not nevative numbers
That doesn't really have to do with our function so it isn't a good reason
f(x)=sqrt(2x-6)
we know the range so far is
[0,
and we want to know what the other side should be
Do you have any ideas for that?
get it from the domain?
Good idea
So we can notice a few things now
sqrt(x) is an increasing function
Right?
As x gets bigger, sqrt(x) gets bigger
ok
yes because we cant have a negative
since its positive its gonna go up
Since the coefficient on the x is positive
yes
Okay so, since sqrt is increasing, and 2x-6 is increasing
as x gets bigger
so does sqrt(2x-6)
right?
wouldnt it be lower since it has square root
We just said earlier that sqrt(x) is increasing
so now we look to our domain
as x gets bigger, our range gets larger
but how big can x get in our domain?
all real numbers
so how big can our range be?
all real numbers
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thank u @devout shale ill try to understand it more
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Is there properties for sqrts ? like $\sqrt{a + b} \le \sqrt{a} + \sqrt{b}$\
And how do I prove them?
Roman_Garland
ah, nice
this is used often enough that some books might call it a theorem
but it's basic enough
as the proof is one line lol
What about $\sqrt{a - b} \ge \sqrt{a} - \sqrt{b}, a, b > 0, a > b$
that's false
You need condition on a and b
or like you can't say in general
can someone help me
Am I right now?
pls
Still, can't comment.
Need a condition like a,b >0
Because what if a=-2 b=-4
RHS can't be commented
Roman_Garland
Now ?
Just square both sides. You'll understand.
If $a, b > 0$ and $a > b$
Then $\sqrt{a - b} \ge \sqrt{a} - \sqrt{b}$\
Proof:
$\sqrt{a - b} \ge \sqrt{a} - \sqrt{b}$\
$a - b \ge a + b - 2\sqrt{ab}$\
$- 2b \ge - 2\sqrt{ab}$\
$ b \ge \sqrt{ab}$\
Oh.... that is wrong, right?
Roman_Garland
.close
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How many 3-digit numbers less than 150 can be formed from the digits 0, 3, 4, 6, and 9? is it 241?
How did you get that
fundamental principle of couting
tell me any number less than 150 formed with those digits
yes those count
039 is just 39 no? and 39 is a 2digit number
padding with zeros counts apparently lol
feels like a pnc problem
its just 25
first get the 1 digit numbers
then get the 2 digit numbers which dont have the first digit being 0
im curious which grade level problems is this that leading 0 counts
It's 4x5 because the four non-zero numbers = 4x4 and once with the zeroes is 4 more?
sure that's one way
i think of it as
__
first digit 4 options
second digit 5 options
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sure thing
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if we have three vectors that are coplanar right then they will all lie on the same plane, but that means the plane is non-specific right? just needs to have same normal vector but they can be any plane (series of parallel planes) right? cuz vectors are translatable in some space
is this related to some other question
if you are told 3 vectors are coplanar, then yes that is not sufficient to find a unique plane (in general)
alright cool, just making sure i got the right idea
not related to a specific question just making sure im understanding y'know
if you are familiar with linear algebra, you get at least 1 degree of freedom from "three coplanar vectors," where the degree is the translation of the plane in space
if you know that their span is only 1 dimensional (so all 3 vectors are parallel) then you get 2 degrees of freedom, where one is the translation in space, and another is the rotation of that plane about a line created by the vectors
if all vectors are the 0 vector, you get 3 degrees of freedom, so any plane will do
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,tex
Let
\begin{flalign*}
& S_1 = \left{ x \in \mathbb{R}^4 \mid 2x_1 - x_2 + x_3 - x_4 = 0 ; \ x_1 - 3x_3 + x_4 = 0 \right}; & \
& S_2 = \left{ x \in \mathbb{R}^4 \mid 2x_1 - x_2 - x_3 + x_4 = 0 \right}; & \
& T_1 = \left\langle (1,0,1), (0,1,1) \right\rangle; & \
& T_2 = \left\langle (2,1,3), (0,0,1) \right\rangle. &
\end{flalign*}
Find a linear transformation ( f : \mathbb{R}^4 \rightarrow \mathbb{R}^3 ) that simultaneously satisfies:
\begin{flalign*}
& f(S_1) \subseteq T_1; & \
& f(S_2) \subseteq T_2; & \
& \dim \mathrm{Nu} \ f = 1. &
\end{flalign*}
renato
!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
@keen steppe Has your question been resolved?
@keen steppe Has your question been resolved?
@keen steppe you've had like 5 people help you with this. i find it hard to believe you dont know where to begin
i mean we found two basis, one for s1 and one for s2 I think
(yesterday)
why not mention that earlier
@keen steppe Has your question been resolved?
@keen steppe Has your question been resolved?
how do I get this started?
@keen steppe Has your question been resolved?
@keen steppe Has your question been resolved?
To find a linear transformation $f: \mathbb{R}^4 \rightarrow \mathbb{R}^3$ that simultaneously satisfies the given conditions, we can start by finding a basis for $S_1$ and $S_2$.
Flamey
@keen steppe
For $S_1$, we have the following system of equations:
[
\begin{cases}
2x_1 - x_2 + x_3 - x_4 = 0 \
x_1 - 3x_3 + x_4 = 0
\end{cases}
]
I cannot see what it equals in the third equation
.
= 0
Let $x_3 = 1$ and $x_4 = 0$. Then $x_2 = 7$. So one basis vector for $S_1$ is $(2, -7, 1, 0)$. Let $x_3 = 0$ and $x_4 = 1$. Then $x_2 = -3$. So another basis vector for $S_1$ is $(1, -3, 0, 1)$. Thus, a basis for $S_1$ is ${(2, -7, 1, 0), (1, -3, 0, 1)}$.
Flamey
@keen steppe
how did you manage to find the basis vectors for $S_1$?
renato
,w rref {{2,-1,1,-1,0}, {1, 0, -3, 1,0}}
,, \begin{cases}
x_1-3x_3+x_4 = 0 \
x_2 -7x_3 + 3x_4 = 0
\end{cases}
\begin{cases}
x_1 = 3x_3-x_4 \
x_2 = 7x_3 - 3x_4 \
x_3 = x_3 \
x_4 = x_4
\end{cases}
renato
,,
\begin{cases}
x_1 = 3s-t \
x_2 = 7s - 3t \
x_3 = s \
x_4 = t
\end{cases}
renato
,,
\begin{pmatrix}
3s-t \
7s - 3t \
s \
t
\end{pmatrix} =
s \begin{pmatrix}
3\
7 \
1 \
0
\end{pmatrix} +
t \begin{pmatrix}
-1\
-3 \
0 \
1
\end{pmatrix}
renato
So one basis vector for S1 is (2,-7,1,0),
no its (3,7,1,0), when x3 = 1 and x4 = 0
@narrow mortar
@narrow mortar .
@here
just change x3 for s and x4 for t but the principle still remains, this is the base I got for S1, is this correct? @narrow mortar
yeah, one basis vector for $S_1$ is $(2, -7, 1, 0)$. Let $x_3 = 0$ and $x_4 = 1$. Then $x_2 = -3$. So another basis vector for $S_1$ is $(1, -3, 0, 1)$. Thus, a basis for $S_1$ is ${(2, -7, 1, 0), (1, -3, 0, 1)}$.
Flamey
For $S_2$, we have the equation $2x_1 - x_2 - x_3 + x_4 = 0$. Let $x_1 = 1$, $x_2 = 0$, $x_3 = 0$, and $x_4 = 0$. Then we get $2 - 0 - 0 + 0 = 0$, so $(1, 0, 0, 0)$ is a basis vector for $S_2$. Thus, a basis for $S_2$ is ${(1, 0, 0, 0)}$.
Flamey
did you read the basis that I gave you, for S1 I got a different result
@narrow mortar
@narrow mortar
For $S_1$, we have the following system of equations:
[
\begin{cases}
2x_1 - x_2 + x_3 - x_4 = 0 \
x_1 - 3x_3 + x_4 = 0
\end{cases}
]
From the second equation, we have $x_1 = 3x_3 - x_4$. Substituting this into the first equation, we get:
[
2(3x_3 - x_4) - x_2 + x_3 - x_4 = 0 \implies 6x_3 - 2x_4 - x_2 + x_3 - x_4 = 0 \implies 7x_3 - 3x_4 - x_2 = 0.
]
Let $x_3 = 1$ and $x_4 = 0$. Then $x_2 = 7$.
We can check that $f$ maps $S_1$ into $T_1$ and $S_2$ into $T_2$:
[
f(2, -7, 1, 0) = (2(2) - (-7) + 1 - 0, 2 - 3(1) + 0, 2(2) - (-7) - 1 + 0) = (10, -1, 10) \in T_1,
]
[
f(1, -3, 0, 1) = (2(1) - (-3) + 0 - 1, 1 - 3(0) + 1, 2(1) - (-3) - 0 + 1) = (4, 2, 6) \in T_1,
]
[
f(1, 0, 0, 0) = (2(1) - 0 + 0 - 0, 1 - 3(0) + 0, 2(1) - 0 - 0 + 0) = (2, 1, 2) \in T_2.
]
Also the null space of $f$ has dimension 1, as required. Thus, the transformation $f$ defined above is the desired linear transformation.
Flamey
yo but getting the eigenvectors in this matter is not rather informal or something, you coudlnt even know beforehand that dim Basis1 = 2 or that dim Basis2 = 1
where did you get the thigns that you plugged to define the transformation f
how are you placing the linear equations you are getting from S1 and S2 in transformation f
how can you tell that the dimension of the nullspace of f = 1?
yo
but $2 - 0 - 0 + 0 \ne 0$
renato
@narrow mortar
@narrow mortar
.close
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i need help with math
i need help with easy math
just ask the question
can i send a pic of it from my book
yes you can
do you know what a scale factor is?
No
it means the ratio between the sides of those two polygons
ok
see that you know the same side (left side) of those two
can you tell me what the ratio between them is?
uuuu i dont no
tell me the length of the left side of the bigger one
6ft
and the length of the left side of the smaller one?
4ft
ok so what is a ratio of 6ft and 4 ft
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are my answers correct? I don't think the last question is?
<@&286206848099549185>
Yo
I don’t think mini modding is allowed here either
okay...didn't realise
Hey I’d help but I kinda need to get some of my work done
Sorry
If ur still here I’ll come back when I’m done
what are you talking about lol
i assume you want to get your answer checked
yep...just the last part...find the traffic intensity.
I'm not sure if the formula I should use is Average Packet Transmission Time = Transmission Delay + Propagation Delay and then ρ=150×Average Packet Transmission Time...or if I should do Average Packet Transmission Time = Transmission Delay (and not add Propagation Delay)
I'm able to wait until you're finished work thanks
all good
scale factor should be 3:2
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For a graph G, if G is connected and bipartite is |E| ≥ |V| - 1?
mini modder that'S a cute name
@short geyser Has your question been resolved?
<@&286206848099549185>
help u with what 🤔
LMAO WHAT 😭
brotha help ur brotha instead of helping me 😭
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$\frac{138+x}{3}\geq75$
pixel
$138+x \geq 225$
pixel
on the right track?
yup
$x \geq 87$
pixel
perfect
pixel
x = 1
x = -2
so i have to find values of x so that
0 is greater than
,calc (1-1)(1+2)
Result:
0
,calc (-2-1)(-2+2)
Result:
0
pixel
pixel
,calc 2/2*1
Result:
1
Result:
-6
pixel
i completed the square
did u learn differentiation yet
no
i think after u complete the square it tells u something about the vertex
k = 6 in this case
and we know that the coefficient of x^2 is positive
so itll be pointing down
the question itself is asking me to prove that every value of 'x' put in that equation would give a value greater than or equal to 6?
yes
if u know that 6 is the minimum point, then all other values of x are either equal to 6 or greater
yeah
so uh what am i even supposed to do now
😭
you basically proved what they asked???
all i did was complete the square
unless im missing something
sorry its late i just wanna finish this question and sleep
yes and that tells you alot
Doesn't it say in the question that completing the square its self proves what you're looking for?
it tells you where the vertex is
and looking at the equation in the form ax^2+bx+c, we know that the coefficient of x^2 is 1, which is positive, therefore the curve is pointing upwards
therefore all other values of x are either equal to 6 or greater
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welcome
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How do u even solve these
for the second one, use L'hopital
I didn’t learn that
factor
you can factor the top
its' a quadratic
after all
it'll just be indeterminate in terms of a
for the first one, horizontial asymptotes is the same as calculating limit as x->inf and lim x->-inf
So the answer is 0
no.
Factorising will be hard, for the limit to exist, you need a (x+2) to cancel from the numerator and denominator, so make x=-2 a root of the quadratic in the numerator
you can see what it is by taking out an x^2 inside the square root, i.e. write sqrt(x^2+3) as
There is no (x+2) anywhere to factor from numerator
$\sqrt{x^2\left(1+\f{3}{x^2}\right)}$
MSC2020 55N31 (Moosey)
then you can pull out $\sqrt{x^2}$ as $|x|$
MSC2020 55N31 (Moosey)
so
What?? How did u get that
$\f{\sqrt{x^2+3}}{x+1}=\f{|x|\sqrt{1+\f{3}{x^2}}}{x+1}$
MSC2020 55N31 (Moosey)
this is the same as sqrt(x^2+3)
this is a common trick to calculate limits going to infinity or -infinity
we can do a similar thing to denominator
$\f{|x|\sqrt{1+\f{3}{x^2}}}{x+1}=\f{|x|\sqrt{1+\f{3}{x^2}}}{x(1+\f{1}{x})}$
MSC2020 55N31 (Moosey)
,tex .exp rules
MSC2020 55N31 (Moosey)
distributivity
Well I already know those
yes but you can think of sqrt() as power 1/2
Then it should be sqrt(x^2) times sqrt(3)
i just applied distributivity to this
But they’re adding not multiplying
x^2 * (1+3/x^2)
i'm not distributing over addition
first, pulled out x^2 from x^2+3, and got x^2(1+3/x^2)
then i split the square root applying distributivity sqrt(x^2)sqrt(1+3/x^2)
then, i applied sqrt(x^2)=|x|
Idk
note that |x|=x if x is positive
it will be if x->inf
so those cancel as lim x->inf
and 3/x^2 goes to 0, and 1/x goes to 0
so what would the limit be?
...no...
$\lim_{x \to \infty} \f{|x|\sqrt{1+\f{3}{x^2}}}{x\left(1+\f{1}{x}\right)}=\lim_{x \to \infty} \f{\cancel{x}\sqrt{1+\f{3}{x^2}}}{\cancel{x}\left(1+\f{1}{x}\right)}$
MSC2020 55N31 (Moosey)
I don’t get how the numerato or denominator turn to those
do you see that $\sqrt{x^2+3}=\sqrt{x^2\left(1+\f{3}{x^2}\right)}$
MSC2020 55N31 (Moosey)
you can think about it as dividing and multiplying by x^2 inside the square root
or just 'pulling out' a factor of x^2
I guess
$\sqrt{x^2\left(1+\f{3}{x^2}\right)}=\sqrt{x^2}\sqrt{1+\f{3}{x^2}}$
MSC2020 55N31 (Moosey)
this is also true. if it helps you can think about it as A=x^2 and B=1+3/x^2
sqrt(AB)=sqrt(A)sqrt(B)
this expression, yes?
both 3/x^2 and 1/x go to zero yes
so what are you left with
@stiff vine
Infinite times 1
$\lim_{x \to \infty} \f{|x|\sqrt{1+\f{3}{x^2}}}{x\left(1+\f{1}{x}\right)}=\lim_{x \to \infty} \f{\cancel{x}\sqrt{1+\f{3}{x^2}}}{\cancel{x}\left(1+\f{1}{x}\right)}=\lim_{x\to \infty} \f{\cancel{x}\sqrt{1+0}}{\cancel{x}\left(1+0\right)}=\lim_{x\to \infty} \f{\sqrt{1+0}}{\left(1+0\right)}$
MSC2020 55N31 (Moosey)
What happened to the x^2
0
if you're referring to here, sqrt(x^2) became |x|
yes. hence they became 0 once you take them to infinity
Jow does that even work
So the answer is 1
HA
yes, that's one of the horizontal asymptotes
