#help-26
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yea
Now did what you did in previous question
We have the sample space where 1 member is fixed
how would ido that with this
12c2?
12 choose 2
oh yea
To form a committee of 2 members
yea
But now we have been given there is 1 girl
So our choices decreases
Now we need to choose
11C1
Only one member out of 11
So this is our total cases or u can say sample space
7 over 11
Now we want the prob. That 2nd member is also a girl
So we choose 7C1
So these are the favourable cases
So now we divide favourable cases by sample space
So what we get?
7/11?
ye
Enjoy
yea
12x11/2
66 total cases initially
Now
They confirmed that one is girl
Oh
Got it
See they confirmed there is one girl
But they did not confirm which girl
So it will be
8C1x11C1/12C2
8x11/67
8x11/66*
@sonic rune try to think
I am going wrong i feel
Our earlier approach was correct
yea idk
wait one sec
ok so ones a girl
and one might be a girl
idk
try working with this ig
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Hey guys, I'm taking Additional mathematics igcse. in one of the topics i dont understand straight line graphs (like the whole thing) it includes dinstance between two points, midpoint, gradient, gradients of parallel and perpendicular lines, can someone give me a example of those type of questions and how to solve it step by step, I'd appreciate it so much
The codes are IGCSE(0606) and 0 level (4037)
do they provide resources to you?
gradient or slope is the
(change in y)/(change in x)
between two points
rise/run
yes
do the give notes/explanations of those above subtopics
$(a+b)^2\neq a^2+b^2$
Skill_Issue
you're not allowed to square terms within () individually like that
wdym
what do you mean
can you show what you'd get in your next step
that's exactly what we said you can't do
what is it
tell me what you think the formula is
ℝαμΩℕωⅤ
you can't square a,b individually like that and/or mess around with the sign in the middle
have you heard of the distributive law
no
for now focus only on this component:
$$(4 - (-3))^2$$
ℝαμΩℕωⅤ
and i'm going to remind you that
you can't square a,b individually like that and/or mess around with the sign in the middle
if you want to expand stuff out, you'd need to apply stuff like the distributive property
but here, the simpler way would be to simplify the (4 - (-3)) first
remember that a - (- b) = a + b
you should probably also learn this
so using that formula, what do you get for (a + b) * (a + b)?
don't overthink
jus try this first
using the distributive law
exponentials
a ^ b
stuff like subscripts and superscripts
b is the index
no
NO
no
simplify it using the distributive law
WHICH IS
(a + b) * c = (a * c) + (b * c)
try it
you've written $x^2,x^1,y^2,y^1$, but those should've been $x_2,x_1,y_2,y_1$, to indicate the first and second coordinates of each point
$$d = \sqrt{(x_2-x_1)^2 + (y_2-y_1)^2}$$
but (a + b) ^ 2 IS NOT EQUAL TO a ^ 2 + b ^ 2
simplify (a + b) ^ 2 using the distributive law
to get the correct formula
try it
yes
and (a-b)^2 isn't equal to a^2 + b^2, or a^2 - b^2
its exactly that
if you want to expand stuff out, you'd need to apply stuff like the distributive property
like above
but here, the simpler way would be to simplify the (4 - (-3)) first
can you simplify
4 - (-3)
no
how are you getting 12
no
4 isn't being multiplied to -(-3)
you shouldn't say that
1 - 1 is -1 would you?
yes
same thing applies here
you shouldn't be multiplying
4 with
- (-3)
remember that a - (- b) = a + b
the latter
the first one was again exactly what we are saying repeatedly NOT to do
also in this situation its easier to just add first
no
remember?
again
4 - (-3) isn't 12
-5^2 = -25
BUT
(-5)^2 is 25
cos negative * negative is positive
only if its inside
cos the ^ comes first
pedmas
powers before multiplication
and the - counts as multiplication
but in this scenario
you are taking (-5) ^2
and negative times negative is positive
YES
yes
and 1 ^ 2 is...
yes
yes
have you learnt surds?
like
simplifying square roots
if not, just leave it as sqrt(50)
@magic elm Has your question been resolved?
wtf, why did all the messages get deleted
yeah wtf
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In this slide, how is it that you can just divide 196 to 980 to get 5?
In order to divide the bottom, wouldn't you also have to divide 0.2 by 196? Or can you just apply the division to that one term?
This slide was on a khan academy video I am self-studying for
Why wouldn't it be a separate term if you still have 0.2 remaining after dividing by 196 on top and bottom
terms are expressions separated by + or -
considering something simpler
2 * 2
divided by 2
is 2, not 1 * 1
Ohhh, that makes sense, you would only have to divide the 2 at the end to get the same result either way
that makes sense, thanks
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@restive inlet Sorry, one last thing. I get that it is the case. But why would you say terms are seperated by + and - but not / and *
how so?
here you could describe this fraction as a single term divided by another
but in another case this wouldn't be the case that it would be a single term divided by another
?
can you rephrase that
I am just asking in what situation would this (the thing I am replying to) not be the case. Because you said it was situational if I understand you correctly
depends onhow you describe stuff
what would be an example of a differing case
980 by itself is a term
0.2 * 196 by itself is a term
980/(0.2 * 196) is the quotient of two things that are individually considered terms, forms a term
Oh I see, so like as you said it would differ depending on how you see what is a term by how you describe it?
give this a read
https://simple.wikipedia.org/wiki/Term_(mathematics)
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I'm confused about the definition of simple curves
From what I know a simple curve is a curve whose not intersect itself
If i am not mistaken a simple curve is exacly that
but when I have to understand if a curve is simple or not I'm not sure
I have an example
I should explain the proprieties of this curve in polar coordinates (if it is regular, closed, simple)
My issue begin since I can say that it is closed since with a multiple of 2pi it returns same values
If i use a graphic processor I notice it doesn't intersect itself, but from definition if shouldn't be rho(theta1)=rho(theta2)
that is not what happens
(so it should be consider as simple curve)
I don't want to confuse you cause i am not sure of my awnser here
Sorry, i talked about this topics some time ago ( also my English is not the best )
I hope someone can help you if not i can give you my perspective
ok np, thank you anyway

while this is the definition I got
so in my case when t1 = 2pi and t2 = 8pi I got exactly that gamma(t1) = gamma(t2)...
<@&286206848099549185>
Yes. What can I help you?
I'm not getting clearly the definition of a simple curve
I wrote also an example I'm not getting
x_Shadow_x
I think you're missing the definition of the curve
I'm guessing your curve is in 2D
yeah
but rho is not a curve here
it's a function
so if you wanna define a curve it's gonna be $(\nu, \rho(\nu))$
rafilou2003
yeah as a parametrization of the graph
rafilou2003
so you never have $(\nu_1, \rho(\nu_1)) =(\nu_2, \rho(\nu_2))$ with $\nu_1 \neq \nu_2$
rafilou2003
what's happening here
x_Shadow_x
If you input 2pi and 8pi, then is $(2\pi,\rho(2\pi)) = (8\pi,\rho(8\pi))$?
rafilou2003
Oh ok I got what you mean
Since - in ( - ,rho(2pi)) and ( - ,rho(8pi)) are not the same
thank you so much
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I have $\frac{d^2x}{dt^2} + 2\gamma \frac{dx}{dt} -w_0^2x = f(t)$ where $\gamma, w_0, t \in \mathbb{R}$. f is real valued as well.\
I managed to solve it by assuming x and f both have fourier transforms but my problem is proving the differentiation property. How do I go about proving $xe^{iwt} \eval_{-\infty}^{\infty} = 0$?
KySquared
I used integration by parts to arrive at $xe^{iwt}\eval {-\infty}^{\infty} -iw\int{-\infty}^{\infty} xe^{iwt} dt$
KySquared
@olive lichen Has your question been resolved?
@olive lichen Has your question been resolved?
@olive lichen Has your question been resolved?
<@&286206848099549185>
as t -> infinity?
@olive lichen Has your question been resolved?
Yeah it would be as t tends to infinity
Sorry I just now saw this
sorry to say
but just like (-1)^n
it doesn't have any limit
But the whole point is that xe^(iwt) must tend to zero or else the differentiation would fail
So it must go to 0

There's no way
The differentiation operator becomes a multiplicative operator when transitioned with a Fourier Transform
can you show your entire work?
That operation would be divergent otherwise
Okay
One moment
Using integration by parts\
$\begin{aligned}
\mathcal{F}{ \frac{dx}{dt}} &= \int_{-\infty}^{\infty} \frac{dx}{dt}e^{i\omega t} dt\
&=xe^{i\omega t} \eval_{-\infty}^{\infty} - i\omega\int_{-\infty}^{\infty} xe^{i\omega t} dt\
&=xe^{i\omega t} \eval_{-\infty}^{\infty} - i\omega X(\omega)
\end{aligned}$\
For this to make sense, $xe^{i\omega t} \eval_{-\infty}^{\infty}$ must tend to zero\
Because the Fourier transform is possible, we know that $\int_{-\infty}^{\infty} \abs{x(t)} dt < \infty$
Therefore, $\abs{x(t)} \eval_{-\infty}^{\infty} = 0$. Thus, $\lim_{L \to \infty} \abs{x(t)} \eval_{-L}^{L} = 0$
KySquared
wait x is a function of t
that wasn't the most obvious
but uh
going from this
to this
loses too much information
?
I just took its derivative
just say that |x(t)| -> 0 at infinity and |x(t)| -> 0 at -infinity individually
and wait a moment
So $\lim_{t \to \infty}\abs{x(t)} = 0$ and $\lim_{t \to -\infty }\abs{x(t)} = 0$?
KySquared
yeah but I'm getting sus of something
?
what are your conditions on x
At this point x is an unknown function
At this point all we assumed is that it is absolutely integrable and thus took a Fourier transform of the differential equation
ok but
there are absolutely integrable functions that don't converge to 0 in extremes
But I thought absolute integrability meant a FT exists
That's what it says in the book anyways
Hmm
Is there some other way I can go about this then?
Other than just making the second assumption "assume x(t) tends to zero as t tends to infinity"
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Mind sending your other steps? I can see why the complex stuff might turn up in the bottom, but I’d like to see how you get there
Never had a problem where that was the case
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d question correct?
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
it is not
yeah, firstly you should understand that [a,b] is a <= x <= b, and (a, b) is a < x < b
so if you have [-5, infinity), what should that be as an inequality?
do i need to show where 0 is
where did the 0 come from?
oh on the graph
it could be a good idea
i just realized i misread your answer, your inequality is correct
i am once again stupid please disregard that
your inequality is almost correct, but notice that the -5 is next to a square bracket, meaning that it's included in the inequality
@steep cloak Has your question been resolved?
OK I FIXED IT
correct?
@cinder sequoia
also i have this question
solve x
im not so good in doing logarithm
logs are all in base 5 can i eliminate the log
how do i do that?
and like make them kind of like exponent
@rigid cloak
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Can someone explain whats going on here
@clever citrus Has your question been resolved?
@clever citrus the sign changes because the direction of dr is opposite between the two curves
Essentially, dr in curve 1 is negative dr of curve 2.
so like one is going counter clockwise while the other is going clockwise (neg)
is that what it means?
That is one specific example of what it is getting at
because I only remember putting this in my notes
the second case right?
where the sign changes
im not sure what the first case means
where there is no sign change
If you have a regular scalar function it doesn't care about direction

It's only when you have a vector function dotted with the differential that the direction matters
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Can anyone take photo and send solution for integration of x sin inverse x?
If u send the solution I can understand it faster rather than explanation it would time to understand
try searching online
we aren't here to do the work for you
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it takes time to do the solution, unfortunately
Took me 4 secs to find an integral calculator with steps. And it only took that much because i have quite a bad internet
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How do I solve question d?
Show the entire question
Be careful of dividing by things that could turn out to be zero
You need to also consider sin(x) = 0 as well and add the solutions to that to whatever you find
0, pi and 2pi from here, the remaining two you have
If that how do I do it?
Well, either don't divide by sin(x), keep it there, and do the rearrangements basically in the same way you have, but at each step (and notably the bottom line as per here) you'll have a factor of sin(x), so you consider cos(x) = 2, cos(x) = -1/4 and sin(x) = 0 (the latter getting you the missing solutions)
Alternatively, at the point you divide by sin(x) (or any other variable for that matter), check where it could be zero (that is, in this case, solve sin(x) = 0), and list those, then find all other solutions and add those to the list too
So at this point you keep the 0, pi and 2pi noted, and then...
...when you find the other two, that's all the solutions for you
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Is it possible to ask for an explanation to what is integration
They already gave you pretty much everything.
first plug everything in the first principle formula
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F
i don't think that would be an issue xD lhopital is so easy to use
but it's not allowed so we can't do that
maybe we can try using the properties of ln
i didn't solve it, i'm giving you ideas, since that seems like the only thing obvious
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these two are the same
Yes
and these two are right angled
correct
so?
i still dont get the mathematics behind it
this angle is 180 degrees + dtheta
ohhhhhhhhh
here i give two 90 degree angles = 180 degree, what's left is dtheta
yeah it's a bit non obvious but it works out
no problem!
if you are done, type ".close"
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how do i break it into partial fractions?
hint : +2x^2 - 2x^2
(the denominator)
what do i do with the x^5 tho
im completely clueless😭
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Can someone explain to me the limit rule in this question
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There are two lines
(2a + b)x + (a + 3b)y + (b - 3a) = 0
And Mx +2y + 6 = 0
They are concurrent
Need to find the value of M
How do I solve this without the family of line formula?
<@&286206848099549185>
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any attempts thus far?
so for the first 2 inequalities im assuming that im just using the definitions of max norm, euclidean norm and manhattan norm, but im not so sure
ig u can use cauchy-schwarz to do euclidean norm and manhattan norm inequality
<@&286206848099549185>
right, for the first one I would just apply the definitions and square both sides, assume |x_i| to be the max from the max norm and the inequality should follow pretty easily. For the second one I would once again apply the definitions and square both sides, then use induction for d to show the inequality (maybe there is any smarter idea?). Cauchy schwarz works well for the third one and the forth one is similar to the first one
@grand blade Has your question been resolved?
wait for the second inequality did u mean the third since thats the one that introduces d
?
$\sum_{i=1}^d |x_i|^2 \leq \left(\sum_{i=1}^d |x_i| \right)^2$
rbit
i bet theres a smarter way but it works i guess
yeh ok i might have a search around havent had much thought into this yet and still got days b4 its due
but cheers
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Hi, i just joined the server, and i could use some help progressing in math in general. I have almost completed a course on khan academy( i dont know if you know it) called algebra 2, with basic trig and some other stuff
i was thinking calc or sum but i really dont know
u can try basic calc now
done exponents and logs yet?
but aren't there more courses between algebra and calculus?
yes the basics of it
algebra 2 and precalc have a lot of overlap
mainly trig might be something new
ok ill look at it
thanks guys
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<@&268886789983436800> they just keep coming
i tried giving him a chance :(
if it's their first post, no tolerance imo
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How do I verify the following inequality in this interval $\left[-\pi, \pi \right]$?
$\sin(2x) - \sin(x) < 0$
if I am not mistaken $\sin(2x) = 2\sin x \cos x$
How do I proceed?
Shadow91518
Can you elaborate?
How about x = 0.5?
@fallow torrent Has your question been resolved?
(If you have a product being negative, what can you say about the factors?)
one of em is negative
if there r 2
so sinx is negative
or 2cosx-1 is negative
or u can say sinx is -ve or cosx<1/2
(true, but that question was meant for OP to answer
)
I am trying to understand, but I think I have some gaps with trigonometry.
Anyway
How come $2\cos x - 1$?
Ps: don't write abbreviated, I'm Italian
Shadow91518
@fallow torrent
,rotate
now for that to be zero
either sinx must be 0
or 2cosx-1 must be 0
do u get it?
yes, I got it.
thank you
so from -pi to 0
sinx is negativwe
and cosx needs to be less than 1/2 in the range or 0 to pi
so i think its wrong
maybe
@vernal matrix
cuz its 1 at cosx=0
and also at x=0
the eqn becomes 0
cuz of sinx
so maybe it does not hold true
@fallow torrent Has your question been resolved?
so I have $\sin x > 0$ and $\cos x > \frac{1}{2}$
Shadow91518
$0 < x < \frac{\pi}{2}$ and $- \frac{\pi}{3} < x < \frac{\pi}{3}$ but I want only the negative part because at start is < 0 right?
Shadow91518
Be very careful when you cancel.
You could do the following...
Let $F(x) = \sin\left(2x\right)-\sin\left(x\right)$
\begin{enumerate}
\item Solve $$ F(x) = 0 $$
\item Solve $$ \frac{dF}{dx}(x) \eval_{F(x)=0} > 0 $$
\item Now, given two solutions, $x_1$ and $x_2$, you know $F(x) > 0$ for all $x \in (x_1,x_2)$ if $\frac{dF}{dx}(x_1) > 0$ and $\frac{dF}{dx}(x_2) < 0$
\end{enumerate}
That is, given two consecutive points where $F(x_1) = 0$ and $F(x_2) = 0$, then $F(x) > 0$ in the region $x \in (x_1,x_2)$ if $\frac{dF}{dx}(x_1) > 0$ and $\frac{dF}{dx}(x) < 0$.
Shuba
Make sense, or want me to explain it further?
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I selected ADE but the answer seems to be wrong ?
those all sound ok
Consider F maybe
Integral test? but cos function is increasing sometimes
doesn't look fun to integrate that too either
my guess is E is wrong
If we took the converging series 1/n³ for example then n³ would cancel out but 3-cos(n³) doesn't exist
but that's just one specific example
my point is that the cosine term may be bothering for limit comparison test
You were right
thanks
may i have help with another question ?
sure
im having trouble with the last part
Hmm okay
Well my guess is they want you to calculate $$\int_0^{0.76} \frac{7}{3}x^3-\frac{49}{6}x^7 : dx$$
𝔸dωn𝓲²s
0.080990392 is my answer
no
you have F(x), so you do not want to integrate F(x) again
it suffices to plug in your value of x
right
𝔸dωn𝓲²s
you heard the man
so i plug in x to my macluarin series
7/3*(0.76)^3 - 49/6*(0.76)^7 = -0.17174689
pretty much
but I noticed how off this approximation is
,w Integrate[sin(7x^2),{x,0,0.76}]
my calculator only gives me up to 8 decimals
,w 7/3 (0.76)^3- 49/6(0.76)^7
add an zero
damn that works 😂
thank you @cursive patrol and @golden blade
I have one more attempt to answer until I can't may i verify my coefficients?
Have you noticed, you can use the geometric series formula?
yes
𝔸dωn𝓲²s
Can you tell me your first value you had previously?
0
how did you get that?
This was not what i had when i used the geometric series
i had something else then i inputted my x for my coefficients, 0 for c0 was the only one correct
x is not your coeffcient
𝔸dωn𝓲²s
𝔸dωn𝓲²s
You are basically considering the first 5 terms from 0 to 4 of your sequence c_n
yea it's the same
ive gotten 0, 1/2, -1/4, 1/8, -1/16
i just pulled out the -1
oh ok
wait
how 0?
You are evaluating $c_0 = \frac{1}{2} \cdot (-1)^0 \cdot \left ( \frac{1}{2} \right )^0$
𝔸dωn𝓲²s
Honestly Idk I put 0 and the website gave me that correct
ah ok
anyway thank you for the help
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I dont understand how that square root of 2x^2 becomes 4x^2
Common denominator the numerator terms
Yes but how do you compute this. I cant seem to find it
Nvm
I just saw the loght
Light*
Thanks
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I’m confused by this a bit. Since when are the rows of matrices representing planes?
matrixes are just another way of writing a system of equations
for (a), the matrix says
x-2y+3z=0 for the first row
and so on for the second
that is how you get planes
Hmmm
I guess I just thought the rows and columns of matrices were always vectors
But now it seems like the rows are planes
And a plane takes three vectors to build so it’s confusing me
It’s like one row contains three vectors if that makes sense
they aren't planes, they are planes through the origin
Planes through the origin yes
Still though those are planes yes
Not vectors
I’m just surprised by that
At first glance looking at a I felt like I was seeing three linearly dependant vectors
in 3d planes through the origin and vectors are close to interchangeable
But it turns out it’s three planes through the origin or rather the same plane three times
I was just struggling with the interpretation of colinearity
Ahhh
Why is the through the origin part so important
For it to be similar to a vector
but actually i realize that in this case they are talking about solution space
so the set of all vectors that satisfy the equality
and it happens to be a plane
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u cannot simplify that much
why? that is the best way of expressing a value like this
!original would help explain stuff better
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well u can just say a = 0.463647609...
so what's the issue with just using a = arcsin(1/sqrt5)
unless you want integrals or infinite sums u wont get much better
cos(arcsin(x)) is sqrt(1 - x^2)
arcsin is just the inverse function of the sine function
so sin(arcsin(x)) is just x
so you can just further apply the sin^2 + cos^2 = 1 identity for some angle A whose sin(A) = x
and that converts it to this
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I tried a bunch of things but the answer was never an option
Show your work
Did you obtain it from ChatGPT?
Really? I wonder what the <@&268886789983436800> think about that?
Could anyone help me with this
!occupied
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4
,rccw
Were you able to do everything before that point?
Since they are equal, the discriminant must be equal to 0
Therefor you are left with an equation
Randel_
It's alright
Thankyouuu
no problem 👍
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have a nice one
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i wasn't able to solve it
like multiply both by 1/x
the numerator becomes 1
and what happens to the denomenator ?
denominator divided by x?
so i'll have 1/x^3 for the first and 1/x^2 for the second
so basically i factorize whats inside the roots
by the largest power
my issue is with the 7-x though
if x > 7 then i would get a - value in the root
which doesn't work
but the limit does work with - inf
yeah it worked
theres no limit for +inf but there is for -inf
does it really matter whether or not it's positive or negative?
it will be in the form of 1/x
so it goes to zero either way
yeah but 1/x^2 goes to zero quicker than 1/x so i would have a negative in the square root
no?
honestly getting the x inside the root when it's negative is very suspicious as well
i recommend that you make a substitution intead of x being -y or something then do it again to ensure that it's positive
what do you mean
you have two limits
one going to infinity
the other is going to -inf
so you solve it twice
once for positive infinity
and another where you make a substitution to change the limit again into positive infinity
there you will simply replace each x with -x
that would be the second limit
huh
so after i solve for + inf
i have to change all the x with -x to solve for - infinity?
i would recommend it
here is what i'm worried about
if you leave it like that and solve for -inf
you put the x inside the root
if there is any value at which what is under the root was negative and x was negative too then this would be invalid
as $\sqrt{ab} = \sqrt{a}\sqrt{b}$ is wrong if both a and b are negative
Mohamed Mohsen
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Help pls
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Can anyone help me find the value of JN
any angles given ?
No
so JN = (3xNM)/2 ?
yeah but should first set that JM= JN + NM = X + Y
and than you know that x = 3y/2
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Can a line be parallel to itself? I want to prove a relation of two lines equivalence. But if it is, then it don't follow the definition of parallel lines right?
parallelism is often defined in a way such that a line is parallel to itself
its just much more useful that way
Is it a convention?
I had learner that paralel lines are those which never intersect to each other
But a line intersects with itself on all points
The more common definition is that two lines are parallel if there exists a line perpendicular to both
its often either included as a special case or it follows naturally from some other def
I guess that makes it an equivalence relation
or you can define it as both lines being cosets of the same linear subspace. that won't mean anything to you but in that case also a line is parallel to itself
sadly that only works in the plane
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Is there a word for replacing a modulo? Like I have $a x+t \bmod p = 0$ and replace it with $a x + t + kp = 0, k \in \mathbb{Z}$. Feel like there's a word for that.
Trapture
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wha
Did you even ping helpers to begin with 
i did not
So what's the relevance of the factoid then, @inner wren?
No
Probably a troll
(as for if there's a word, I don't know of one myself)
You could say residue
ax+t has residue 0 mod p
Well I guess this still has the word mod
Ah, I don't need a word I just thought there was a standard term
The term is the one you want to replace
Mod is the standard term
So far I just wrote "I replace this with that so we can do blah"
By the way modulus and modular arithmetic are not connected
mod doesn't mean modulus
I don't think it does anyway someone can correct me on that
What else would it mean?
Modulus usually means | |
It's modulo
Yeah, no 😄
All good
quotient group/ring

In "mod n", n is called the modulus
By some people
They are more connected than me with reality
But it's also absolute value for complex
(well, modular arithmetic is the one of the first examples of these
)
I'm sticking with integers, so no danger of confusion there
Also like every other measure I think uses the word modulus to mean || ||
sometimes a rational sneaks in but i know how to deal with those
Anyways, seems like there's no word for whatever I'm doing, thanks folks 😄
Modulo means "with respect to a modulus of", according to Wikipedia
So modulo n (or mod n) is "with respect to a modulus of n", where n is indeed the modulus
damn
Apart from some variation on the word "equivalence", I don't think there's a specific word for what you want
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Is there a proof of
the factors of a number are unique till till the first factor is smaller than or equal to it's square root
If we start factoring in ascending order of the first factor
It's used in the sieve of erathosthenes
I am not quite sure what you mean by that sentence
do you mean the fundamental theorem of arithmetic?
that the prime factorisation is unique?
if you just have factors then they arent unique, there are lots of ways to factor a number
@desert apex Has your question been resolved?
No what I meant was for every composite number their factors are repeated twice
For example factor pair of 36
1 x 36
2 x 18
3 x 12
4 x 9
6 x 6 <-- square root of 36
9 x 4 <-- after square root all factors are repeating
12 x 3
18 x 2
36 x 1
My English is bad,
But I hope you get my point
Is there a proof that for any composite number the factor pairs are repeating
yeah i get you
i use that a lot in checking if a number is prime
hmm 
I tried looking for the proof
But couldn't find it
I mean I think it’s kind of too simple to have a famous or named proof.
You can prove it by showing that if q is a factor of n, then n divided by q is also a factor of n.
No what I meant was the factors are unique till the square root of a number,
After that the factors are repeating
either q or n/q is <=sqrt(n), otherwise their product would be bigger than n
well they are repeating because they appear in the different order
3x12 appears before sqrtn and 12x3 occurs afterwards
Yea I know but I thought that there might be a proof
well I mean this is a proof basically
We just proved it together 🙂
But this is just observation
well and we explained why it happens
a proof is basically just a proper explanation of why something always happens
Observing facts and drawing conclusions are what we mean when we call something a proof.
I meant like a rigorous proof
this is rigorous
