#help-13
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alright, please
So the 2nd sum is (n + 1) + (n + 2) + (n + 3) + ... + 49, right?
aye
You could rewrite this as (n + 1) + (n + 1 + 1) + (n + 1 + 2) + ... + (n + 1 - n + 48)
But this is the same as 0 + 1 + 2 + ... + (48 - n) + n*(n + 1)
What I did here was take out n+1 from every term of the sum
i see...
Oh wait I think it should be (48 - n)(n + 1) there
Because in the sum there are n - 48 terms
Wait let me think for a moment
ok
Yeah so the sum is now 1 + 2 + ... + (48 - n) + (48 - n)(n + 1)
We could use the formula here to rewrite this as (48 - n)(49 - n)/2 + (48 - n)(n + 1) I guess
Is that product of (48 - n), (n - 1), (48 - n) and n divided by 2?
Btw I messed up a bit there, should be (49 - n)(n + 1)
idk...
this hw is stressing me out
Yeah so the 2nd sum is basically this
Now all we need to do is set 1st and 2nd sums equal to each other
So what we have is this
The rest is solving for n
i see
ok, ill see what u can get from here
also sorry to ask u for this, but can u stay here please? i got 2 other questions that im stuck on as well
Surely
thank u a ton
Might get a bit busy soon but I'll try to respond anyways
its part 2
i asked others in the other hw help qu
but they didnt understand
first of, this isnt an infinite series
its finite to the term of n
second, x is not less that one in this case
differentiation comes to my mind
cant do diff, have to use xSn
hold on, lemme get the paper out, its like the 3rd time i tried to redo this question
it just seems like it to me but idk
idfk either 
look this thing is geometric series
write formula
everything before last line is ok
oops
its geometric plus an extra last term
$$1 +x +x^2 + x^3 +... + x^{n-1} -nx^n$$
Shuri2060
I believe, but check.
got the same as well
...ignore what i wrote on top
ok... i think i got a solution
imma check, by plugging in values x=2 and n=4, i should get 49
i got it....
I GOT IT
AAAAAHHAHAHHAHA
FINALLY
@jaunty mural @south tundra THANK U, NOW SEQUENCES CAN GO KISS MY ASS
HW FINISHEDD
AAAAAAAHHAHAA
THANK U AGAIN
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hi, i need help
sorry for the bad quality pic
<@&286206848099549185>
<@&286206848099549185>
You would find the height by letting t = 0
height of the bridge?
Yes, because the rock falls from the bridge. So at the beginning, the height of the rock is the height of the bridge
oh okay
How would you find the maximum height of the rock? You could try sketching the quadratic equation
wait so the answer for a is 15 right?
then how is the rock at 25?
Set h = 25 and solve for t
Is it possible? Can you get any answer?
nope
didnt work
Yes, and what did you find as the maximum height?
So for d) you could write 'never'
is that a thing
i think we are doing something wrong
<@&286206848099549185>
Why can't it be a thing? Try drawing the quadratic for the height
I finally understood the whole thing. Thank you!
@cedar kiln
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Is the point of inflection on a cubic graph also the midpoint between the minimum and maximum points of the curve?
@deft spruce Has your question been resolved?
Shuri2060
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Hi, I'm a bit stuck on trying to figure out if a certain sets of datapoints are generated by a discrete uniform random number generator. The cases I'm having the most trouble with is cases where there are a low amount of samples, or a high amount of possible output values. Ideally I would like to calculate a p value to see if I should reject the null hypothesis that i'm dealing with a discrete uniform generator. I did realize that the amount of times a certain value is hit is distributed according to a binomial distribution, however I am a bit unclear how I should use this to test my null hypothesis.
An example of a data set (at least the counts of the elements)
62 48 59 70
(searching for tests that confirm or reject uniformness all lead me to pages about the uniformity of p values)
What’s your alternative hypothesis
so for a binomial distribution with n = 239 and p=1/4 the chance that 48 or smaller comes out is 4.4%
that it isn't uniform?
I don't know if I can make a better alternative hypothesis
well, a alternative is that it is correlated to other attributes of the datapoint
like if I only look at the data points that also have a certain attribute, I get the counts 11 10 13 26, which my guts say is not uniform, but I can't really prove it
I have one other idea
one way of defining a p value would be:
if I generate data sets according to my null hypothesis, what is the probability that my given sample lies further away from 1/4,1/4,1/4,1/4 then this random sample according to a given distance metric
I think that should use the taxicab metric
as then equally likely situations lie equally far (I think)
So yeah it would be like
something like "there's a p % probability for this particular datum to be situated where it is"
But I'm trying to find a real method fo rit
that for every data point
https://www.investopedia.com/terms/g/goodness-of-fit.asp @humble ledge
The goodness of fit of a statistical model describes how well it fits a set of observations. Measures of goodness of fit typically summarize the discrepancy between observed values and the values expected under the model in question. Such measures can be used in statistical hypothesis testing, e.g. to test for normality of residuals, to test whe...
This has it fully laid out
So you're basically making a histogram like this
You're histogramming your data into "bins" and comparing the size of each bin to the expected result
and then you should get a statistical answer
Does this make sense?
I think making your number of samples the same number of data points might be good
euh
In that case given your data, your value should be $\chi ^2 = \sum_{i=0}^n{(O_i-1)^2}$ where $O_i$ is the number of data points within the region
Er, that's wrong
KurtDee
This is giving me a p value of about 0.98% for 11 10 13 26
What's your max
what do you mean max?
0-3
11 is greater than 3
yeah, those are the counts
right, so chi squared would be the euclidean distance (squared) to [1/4, 1/4, 1/4, 1/4] * n
I'm not sure I understand
to be honest, I think using taxicab distance is more correct
euh, nvm, I'm dumb, I think
I'm not sure what this distance is
Yeah
I was just doing it in excel lmao
I think the calculator I used used two tail
Two tailed makes sense
@humble ledge Has your question been resolved?
But this graph has no maximum nor minimum points
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To answer your question, the inflection is in the middle of the min and max, if they exist
Alright, thanks. I think my question clearly implied that the min and max had to exist in order for the midpoint to be in between the min and max points, so I'm not sure why the other person answering me dismissed the obvious implication
The inflection point is the max/min of the quadratic differential which is in the middle of the 2 zero points, which are the min and max
@deft spruce also interesting: a cubic function is point symmetric around the inflection point
Wait is it
I'm not sure anymore
Wouldn't that imply that the concave and convex part of the graph were identical in size?
OK, and apparently that is consistently true across graphs?
"The graph of a cubic function is symmetric with respect to its inflection point"
Yeah, seems like I remembered it correctly
Graphs are cool
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do you know what the argument of a complex number is_
the intuitiv definition is that it is the angle between the positive real axis and the number.
oh yeah its that one
i.e. arg(i) = pi/2, arg(1) = 0, arg(-i) = 3pi/2
The anticlockwise angle from the positive real axis
The range it can be depends on definition
-pi to pi or
0 to 2pi
-1 +√3 i ..... i need to get it from this complex number
but when i do the math it gives me -60°
and it should be 120°
the argument
yeah that is different
even if you accout for what Shuri said.
Can you make a sketch?
with the cuadrants?
yes
i have it
If you sketch it should be clear that 120° is about right
If you're working with complex numbers, you really should use radians not degrees
just going to say
You can think in degrees, that's fine.
yeah im using radiants but im not very good with them. its easier to ask in degrees
Anyways
but yeah thanks
i pass it to radiants afte
yes
so more than 90° aka pi/2 and less than 180 aka pi
Actually I think it is always helpful to sketch this or imagine it how it looks
that is how I figure out the right range anyway.
and how do i calculate it?
lets say if i cant see it in the sketch
then subtract from 180
???
Of course you have to sketch
Not sketching is bad
Sketch in head
or sketch on paper, doesn't matter.
I would never do it without.
In particular, you need to know which quadrant the number is in, otherwise you will fail to work out the angle.
You could memorize the cases table but it's not a good idea imho.
its not.
i mean in the first quadrant both imaginary and real are positivw
and the forth both are negative
nooo
I don't think we agree on the quadrant labelling
so the process of getting the argument is the same
yeah yeah, thats how i see it
The process isn't the same
or if it is
I strongly suggest you don't consider it to be
Just get used to quickly sketching an argand diagram
This takes like 5 secs on paper
so its only like a visual thing to calculate it?
yes.
oh okay
I can see the angle between 0 and 90 i need to calculate
and then I see if I add? subtract?
to 0, 90, 180, 270, 360
whatever it is
yes, i see what you mean
One thing that is maybe worth memorizing is that if it is only at the right side (quadrants 1 and 4), then you can calculate it as atan(imaginary / real)
keep in mind though that it needs adjustment when it is not at the left side.
yeah thats how i was doing it
aha
but when i do it like that it doesnt give me the 120°
yeah because you are at the left side
as you can see
imaginary / real
gives the same answer
if you negate both.
and to do that i just do √3/-1
If it is at the right side you would need to add or subtract 180° aka pi (both are fine depending what definition you prefer)
I suggest to follow Shuri's advice though to sketch also.
yeah the thing is i need both
the sketch and the process
and i cant finish understanding the process
i know i should do arctg (√3/-1)
but im not sure how to solve it
Unfortunate it does not embed the image
it shows the table of cases if you wanted to figure it out without any sketching at all.
you are welcome
I think this is hard to memorize though without at least sketching in your head.
no yeah i know, i always do the sketch first
but if i have to do an exam of this i need to write how i got it
thats why i cant just do the sketch
Hm if I was the teacher I would accept that obviously
but if it does not work for you, oh well
btw I think neither me nor Shuri meant ONLY sketch
we were talking about sketching as a help to figure out the right case.
yeah i always sketch
and its rather easy to see how much is the argument
its just that i dont get the math of it
when i do it myself
and i clearly dont know how to use the calculator bc im not getting anything close to that °
120°
but thanks a lot, its really nice that you guys are helping peoplle
ill close it now, have a great day 🙂
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I need help determining linear independence, I understand that its making a linear combination of the vectors equaling the zero vector but i'm not sure y i keep getting it wrong.
rn i just think A, C, and F are Linear independent <@&286206848099549185>
You need to stick the vectors into a matrix equation set equal to the other vector(s)***
And solve
If there is only one solution the vectors are linearly independent
Other pointers
Any set with zero vector is NEVER linearly independent
Even just the Zero vector by itself
So A is not Lin Ind
Also a set that has more vectors than entries in the vector cannot be linearly independent
E.g. set of 3 vectors with only 2 values in them
F would also not be LI then
Correct
So if you have only 2 vectors
You just try to find a scalar constant that multiplies one into the other
If you cannot find such a number, then those are independent
E.g.
(1,2) ; (3,3)
There is no constant that can turn one into the other
I can solve it algebraically out by entries to be sure but i think you should see that one intuitively
But take a look at
(1,2) , (2,4)
Multiplying the first one by scalar value of 2 gives (2,4)
These are not independent
right, is this the only thing im looking for in a set of vectors when determining if its LI?
oh
Because e.g.
(1,2), (2,1), (3,3)
Any 2 of those are independent wrt each other
But if you take
(1,2) + (2,1)
You create (3,3)
Adding different multiples of vectors is what we call a linear combination pf those vectors
The real definition of linear independence relies on linear combinations of all the vectors
So if i can add different multiples of vectors together to create one of the others in the set
Then you do not have independence
In order to check for sonething like D.
You need to use a matrix equation
First determine if any 2 of the vectors are independent
my work on D
This is how i would approach it
Well
Actually your way is fine
For 3 vectors with 3 entries
When you have as many vectors as you do entries, you use the homogenous equation you setup
That equation has only one solution if and only if the vectors were linearly independent
But personally i would stick the first 2 vectors in a matrix and solve for the 3rd vector
If there is no solution, then you have linear independence
I prefer that way of thinking because it works for any size set of any type of vector
ok so is C LI since its one vector
Yes
G. Is another good example
Definitely NOT LI
Because more vectors than entries in the vector
(Which means more vectors than there are dimensions in that vector space)
because the space is Real^2 and there are 3 vectors?
ok i think i understand the content
ty i will answer these now
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hi so
I have to use gauss elimination to calculate the inverse matrix
and at the end I get the correct answer but with 5s instead of 1s on the left side?
is this still correct?
any help would be appreciated
,wolf {{-1,7},{-2,9}}^-1
@glossy root Has your question been resolved?
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i solved this question but idk where i went wrong
Oh..
so post your attempt...
idfk what i’m doing lmao
o i just did line eqn wrong
yep
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guys does anyone know how to begin proving this is true for all xeR?
What tools do you have available?
what do you mean by tools?
perhaps sin(a+b) identity would be a good start
i tried that but it seems useless
One tool that is incredibly powerful with this kind of question is to use the complex number exp identity but I am not sure if you are allowed to use that.
we wouldnt be suggesting it if it was
you mean sin(x + 2x)?
i think everything is valid
sin(x) = 1/(2i) (exp(ix) - exp(-ix))
going from there to double angle identities maybe ?
it's the most intuitive thing to get sin3x in terms of x
Using this single identity plus usual exponentail stuff I am pretty sure one can do it easily.
But I don't wantto confuse you with complex numbers if you haven't seen them.
no its all good ive heard about them
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guys how can i know if this series converges?
what tests do you know
for convergence
actually, can you post the full problem first
this is the test you want to use, yeah
quotient criterion
thats fine
Okay, so its actually asking you if the sequence (x_n) converges, not if that series in particular converges
this is equivalent to asking if the infinite series converges. It is interesting that they didnt just ask you that outright
so with the sum?
Migillope
so this means sum from n->inf ?
If there is a (-1)^n thing in it your alarm bells for the Leibniz criterium should always start ringing.
No, thats the sequence of each of those sums with upper bound n
so the first term is $\sum_{k=1}^1 (-1)^k \frac{1}{\sqrt{k}}$
Migillope
the second is $\sum_{k=1}^2 (-1)^k \frac{1}{\sqrt{k}}$
Migillope
etc
so as n gets really really big, itll get really close to $\sum_{k=1}^\infty (-1)^k \frac{1}{\sqrt{k}}$
Migillope
okay i see now
which is why if we can show $\sum_{k=1}^\infty (-1)^k \frac{1}{\sqrt{k}}$ converges, we're done
Migillope
its so difficult because there are so many criteria
yeah, but as @drifting matrix said, if you see a (-1)^k in the series, you should immediately use leibnitz criterion
(I prefer the name alternating series test because it makes it a lot easier to remember what it actually does)
i see
anyway, do you see how to solve this using the leibnitz criterion?
so this would be alternating too?
no, there is no (-1)^k here
oh i thought because of cos()
okay but youre right I'll have to try to solve a) first
no matter what power you raise e to, it will never be negative
so there is no alternating ness
although, you might want to examine part b by saying "well if the exponent converges, then the sequence converges"
then you can probably use alternating series test
but we can cross that bridge when we get done with a)
ok thank you very much
ping me when you are done (or stuck at some point) on a
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@west dome hey i think I did it:
first: i set 1/sqrt(k) as my x_n
second: i did the lim of x_n, which was 0.
third: i proved if x_n >= x_n+1, which was true
but im not sure how that proved a)
oop
is it possible to find the actual value it converges to, or would that be too difficult?
you could. my german is rusty, but the question just asks if it does converge, right?
I think finding the limit would be difficult in this case.
,wolf sum (-1)^n/sqrt(n), 0<n<oo
They're trustworthy steps, seeing as how it is the alternating series test, which isnt too hard to prove!
Alright
so @fair narwhal did you want to do part b?
yes
ok, do you have anny ideas
there is another tip for this i think: if no limit exists, check if an accumulation point exists
so something with this
i can maybe just use the cos pi sqrt(n)?
yeah so we have the condition that exp(cos(...)) converges iff cos(...) converges
so: you need to test if cos(...) converges
ah but cos never does
to 1
since 1/n -> 0 as n-> infinity and cos(0)=1
so, you need to look closely at pi*sqrt(n)
does this converge?
uh... logic. I'm not sure the name of the criterion, I can check if youd like
Divergence test
there it is
well, its a little more complicated
if the inside of the cosine had the sequence 0, 2pi, 4pi, etc, then the inside diverges to inifinity, but cos of the sequence is constant (1) right?
essentially, you need to show that $\pi sqrt{n}$ doesn't converge and that it doesn't start repeating values for which cosine is constant
Migillope
i.e. doesnt look like some $\theta + 2\pi k$
Migillope
well, I suppose it could alternate between values on which cosine has the same output, but it doesn't need to be so complicated. Do you see what I'm getting at?
No
ok, let me draw a pic
because for me it looks like an alternating series
the cosine alternates, the e does not
you can probably use alternating on the cosine, but its complicated
anyway, cosine goes around this cirlce
if the argument of cosine (here, $\pi \sqrt{n}) keeps landing here, what happens?
that should be pi/4
i dont understand, how should i know what cosine(pi*sqrt(n)) is
you mean cosine(pi*sqrt(n))?
Okay lets work from there, why is it either + or -
because cosine is either + or -
at least for pi*sqrt(n)
for lets say 2* n *pi its always 1 like you said
right! So the point is that
- pi*sqrt(n) does not converge
and - It doesnt start repeating values on which cosine is constant. We can show this by nothing that if you take the subsequence where n = 1, 4, 9, 16, etc, our sequence becomes $(\pi \sqrt{1}, \pi \sqrt{4}, ...)$ which is $(\pi, 2 \pi, 3 \pi, ...)$
Migillope
make sense so far?
yep
Migillope
-1, 1, -1, 1
right!
since we we have a divergent subsequence, the entire sequence is divergent
this shows that $cos(\pi \sqrt{n})$ is divergent.
Migillope
Migillope
@fair narwhal would you like to go over it one more time or do you get it?
does it ask for that?
sadly
uh, well. The sequence diverges.
accumulation points are the limit of the sequence
(b) has infinitely many accumulation points, every point in [-1,1] is an accumulaton point.
but this is pretty difficult to proof rigourously I think.
? the sequence diverges, it has no accumulation point
no
accumulation point just means that it touches any neighborhood infinitely often.
As the picture says in german
ah, I was looking at the wrong defintion
"if NO limit point exists, figure out if there is an accumulation point"
can you explain that for dummies
Luckily it does not ask for a specific accumulation point
so there is a simple argument that there exists one without finding one concretely.
what part exactly?
how i can see if theres an accumulation point
we always did it with lim sup, lim inf i think
First is it clear to you what an accumulation point is?
ummm
Maybe we should talk about this first?
a point where many (infinite?) points touch it
yes intuitively
there are at least 2 formal definitions:
- there exists a subsequence which converges to this point
- a point x such that for any epsilon > 0 and arbitrary N, there exists n >= N such that |x_n - x| <= epsilon
the what now????
it's kind of the same thing
yea i stopped trying to figure out the epsilon thing a long time ago
that's not great
maybe i'll understand it next semester
For our intents and purposes we can work with the first definition, which hides the epsilon inside the convergence.
ok great
so we basically discard any sequence elements we don't like to get a convergent sequence
let me give a simple example
so if the sequence diverges all the subsequences diverge too
x_n = (-1)^n
this is not convergent as you can see (maybe draw a picture, it goes between -1 and 1 all the time infinitely often)
yep
makes sense
they are touched infinitely often
using subsequences x_2n and x_2n+1
the even and odd sequence entries
okay
So I think for our specific example we just need to know one important property of sequences
which is often called compactness or Bolzano Weierstraß property
it says that if a sequence is bounded then there exists at least 1 accumulation point
The intuitiv idea is that the elements must be "somewhere" and since the sequence is bounded they can't escape
so somewhere there gotta be a lotta elements
thats true
Given this property you get that there is an accumulation point
without doing any real calculation
wait thats so OP
🙂
if it is divergent to infinity then you cannot apply it
since it's not bounded
actually if it divergent to infinity there will be no (real) accumulation point
same with minus ininifty of course
yeah as I said I am pretty sure every number between 1/e and e
is actually an accumulation point
that would make sense yea
but luckily we don't need to proof that
alright i understood it now
yay 🙂
thanks to the both of you
You are welcome
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indeed, since our function is continuous and oscillating between these two values, every point between is accum. pt
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how do I find the anti-derivative of x / (x^2 + 4)?
none of the rules on my trig sheet apply to this
looks like a u sub
you have the derivative of your denominator as the numerator, off by a constant
normally calls for a u sub
a disappointing son
wouldn't it be du/2x? not just over 2?
well i can just divide by the 2 here
still the same thing, just keeping x on the other side
makes it a bit easier to see
they do, yes
u sub makes me shudder
1/u * du/2 = 1/2 * int[ 1/u du]
looks good i think
Calculus class leaves scars
don't diss the u sub :(
which is 1/2 * ln |u| according to the anti-deriv sheet
indeed it is

Engineers when they're not given a sheet with the answer to every integral in existence:
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Hilf mir
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what are the possible values of k expressed as an inequality if y=-x+3 and y=k(x+1)-1 intersect in the first quadrant
well
first lets graph it in desmos
we know
that we can find a range for k
by finding the value of k that would result the second equation passing through (3, 0)
and by finding the value of k that would result the second equation passing through (0, 3)
the rest is just algebra
ok thanks
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How would I do this question?
properties of the discriminant
But There’s an extra variable that’s confusing me
consider b+1 to be the constant component of the quadratic
as long as the D is greater than zero or equal to zero
b^2-4ac has to be greater than or equal to zero
now
the b doesn't actually mean the b in the equation
it means the b as in ax^2+bx+c=0
which part don't you get
1-4(2)(b+1)>0 or =0
How to start solving it
B squared -4ac
do you know what the variables in that expression represent?
Yes
can you apply that to the quadratic you're given
Except in this question I don’t get what’s the variable C representing
Yes
do you know what the variables in that expression represent?
yes
Except in this question I don’t get what’s the variable C representing...
that's a bit contradictory
c represents the part independent of x
b+1
which people refer to as the constant
consider
b+1to be the constant component of the quadratic
Oh ok I get it
Ok I got it thanks
I have another question
How would I do this question?
yes
yes
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Hi! I have a question on this problem; I don't have any work available at the moment as I don't understand what the question is asking. Is the first step to set the equations equal to each other and then solve from there? But even then, I wouldn't know what to solve for.
(I'm new to the server, please let me know if I'm doing something wrong)
I'm going to sleep soon so it might take me a while to respond after some time
@dense dawn Has your question been resolved?
damn teacher why you giving proofs to 8th graders
start with $ax^2 + bx + c$. do algebra on it until you get $a(x-h)^2 + k$. first step might be to factor out $a(x^2 + (b/a) x) + c$.
riemann
So basically turn standard form into vertex form?
at the end of the algebra, you'll be able to write $h$ as something with $a, b, c$ and same for $k$
riemann
correct
Ohh
8th grade teacher assigned this?? sheesh.
Nah, 9th grade lmao
okay still
oh then that's completely fine /s
my undergrads cant do this
lol
Zizi's in honors algebra for sure
80% of her high school grads go to Harvard/MIT/Princeton/Stanford
Zizi_Sunee
$a$ is the same, $h=b/2a$, and $k=(-b^2/4a)+c$ i think
Zizi_Sunee
you can always verify by plugging it in and simplifying
that's my way of telling you that you're almost there
hmm ok so now i have to find a, b, and c right
i mean plug in your values of $h$ and $k$ into the vertex form
riemann
$a \left(x - \frac{b}{2a}\right)^2 + \frac{-b^2}{4a} + c$
riemann
does that equal the standard form?
no? (guessing at this point)
ok so thats the values plugged in, right?
those are your values, yes
i don't really understand what i'm supposed to do next, though 🤔
expand this and see if it equals $ax^2 + bx + c$
riemann
you can think of it as a "verify" step
this is equal to $ax^2 - bx +c$
riemann
yes
you're supposed to get this
you just have a sign error on h here.
Zizi_Sunee
whoops i meant $a(x-(b/2a))^2+(b^2/4a)+c$
Zizi_Sunee
Oof I gtg sleep
riemann
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The number of solutions of the equation [2x]-[x+1]=2x (where [ ] is the greatest integer function) is?
@spiral onyx You know what greatest integer function is?
yes but im kind of confused about the question
like i haven't solved such questions on GIF before
Can you find at least one solution? @spiral onyx
That would be my first attempt on doing such guestions.
For example 0 is the solution or not?
how is 0 a solution....
I'm asking you, is 0 a solution or not?
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check if it's diagonalizable
oh i see
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just a quick question, would i need to use u-substitution to integrate this?
nuu, it's standard integration
hmm, i think it would be easier if you multiply 2 with x^3 and -x and then you just need to integrate each term apart
you just multiply it out, split the integral and just integrate the polynomials
actually you dont even need to multiply it out since integrals are linear
ty
do i need to split them or is that just to simplify
its in the context of this problem
Or just extract the constant outside the integral
Wouldnt they want you to evaluate it
I guess that doesnt evaluate to the right answer
Also whyd you split the integral?
it doesnt care if i evaluate so i usually dont
just so theres less margin for error
and i split it because of the two different areas
You have to deal with that negative area, no?
yeah so i set it up as
well idk how to use the bot to write it so ill take another picture
,rotate ccw
srry
its the bottom one
the integration from -1 to 0 + the integration from 0 to 1
Why not just fundamental theorem it
F(1)-F(-1)
Rather than F(1)-F(0)+F(0)-F(-1)
ohhh
The F(0) cancels out anyways
You have to do the integral from -1 to 0 MINUS the integral from 0 to 1 to account for the negative area, I think
didnt work either
What did you input?
But we don't want the signed area, no?
i just tried subtracting instead of adding
So we gotta account for that?
Oh is that what they want?
I'm assuming based on the wording
it was total area
so the first part on the left was 1
and the second part was 1 as well
answer was 2
i honestly thought they would cancel out but here we are
They would cancel out if it was signed area
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how do I solve
Im making a function that returns a and b
x1, y2 can anywhere, behind it, above it, below it, in front of it, etc.
Oh. Uh one sec i think i can help with this one
you could go about it using trig
I just need a and b's values
I know
but i think you can also go about it using scaling i think, that might be easier, do you want that way?
just any solution I can understand / implement in programming
do you understand basic trig functions?
oh that does noy have have a back ground
hold on wait, i really think this will be easier with just scaling
yes I know this...
give me a moment to work out a gaood way to explane
so if we have a rectangle and we cut the side lengths in half the resulting red rectangle is 1/4 the size in area
and if we make the length of the rectangle 1/3 then the area is 1/9
what im trying to show here is that there is a relationship between scaling so and the area
k
i think I get what ur saying
what's the scale in this
I can figure out longer sides
and the long line in the middle
I know the small line in the middle in the small rectangle is 10
so if we make the rectangle
1/2 length the area ia 1/4
1/3 length the area is 1/9
so if se scale the rectangle to
1/x length the area is 1/x^2
ON WAIT
the length of that line is 10? no the area of the small rectangle?
yeah
length of that line is 10
sorry
I didn't clarify
lmao, i was assuming the area of that square is 10
this is a much easer question now lol
when you uniformly scale a triangle the ratio between the side length stays the same
ok one sec
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Is 24° correct?
If not what's the correct answer?

