#help-36
1 messages · Page 213 of 1
what about the 3rd and forth quadrant
the theta should be the angle that the curved arrow is showing, not the one under the line
what’s a theta
and what’s the
tae
kinda like coordinate lines
like making a straight line
tae?
.
tae
theta is how θ is pronounced
It's the angle between the x-axis and the line
'The reference angle'
yea, positive x axis to be more precise
oh ok ok
Oh Cartesian plane
the b) question here, tey wanted to know how they should represent it and apparently they needed to use the coordinate system to represent is and not just a trangle
If Tan and Sin both are +ve it means we're talking about the first quadrant
what’s ve
+ve is a shorthand for positive
oh ok ok
Positive, i mean
i only understand it as the y and x are positive so the first quadrant
y is ve and x is negative so second
both y and x and negative so third
- Sin^2 x + Cos^2 x = 1
This will be the line y=x
I don’t get this
So which grade are you in right now
Do you understand what the slope of a line is?
It's used in coordinate maths
10
yes
👍🏻
huh?
How much do you understand trigonometry?
Like do you know that trigonometric ratios?
thats not a graph for line
idk the name but maybe i do know it
ik the formulas
how fo ind th enable
and side
angle
Yes pls elaborate
and side
i mean Sin^2 x + Cos^2 x=y would be 1=y so the graph would be the same as y=1
i dont get where you got y=x from
Yes you're right
Sin^2 x + Cos^2 x=1 would even be a graph thechically since you would need x and y
Idk why I went to tan 🤦🏻
anyw skittlx u can ignore what weve been going on abtw
once sec
a vid would probably help
I don't think so
You don't learn that in 10 grade
I’m not sure what radians are
i learn just for learning sake, I don’t learn like the terms or like the topic names with my learning
yea i was confused cuz i learnt about the coordinates and radians in 11th, and only triagles with angles below 90 in 10th
Yea same
Do you know how to find out the value of the trigonometric ratios if any one of them is given?
You must have learnt that in school
what exactly is a trigonometric ratio
is it the sine rule
cosine rule?
Right, so all the 6 ratios let me name them
Sine
Cosine
Tan
Cot
Sec
Cosec
These all are the trigonometric ratios
Heard of them? @gritty flume
ig so
i just found out what the cot, scs and sec meant
We deal with the Right-Angled Triangle with these 6 ratios.
oh yes
and the triangles without is the other two
?
sine rule and cosine rule
What do you know about them?
the formula
idk when to exactly use the cosine rule tho
ill be closing the channel after an hour bc ill learn something else and relearn math
I don’t think so
unless your referring to the opposite side
adjacent and hypetenuns
Yes talking about them
oh ok
do you know how sin and cos
are defined
in the coordinate system
I don’t think so
yea, thats probably hwy you cant understand why its negative
isn’t it bc the x is negative
the way sine and cos are actually defined is by considering a circle of radius r centered at the origin
then if you draw a radius making a angle θ with the positive x axis
Showing her the visual illustration would be better
sin=y/r
cos=x/r
School teaches it with a Right angled triangle😭😭
this?
yes
i kind of get it in a way
i was trying to find a vid but they all had radians
😭
what are radians
i mean its easy to understad i can send you a vid one sec
oki doki
ty
Just know that
180° = π radian
You understand degrees right?
yeah
You can convert any angle into radian with this relation
oh ok ok
they way i would explain it: basically, its a way we define angles so that we can use pure real numbers instead of degrees
we consider a unit circle, if a given arc of a=the unit circle(radius=1) subtends a angle of θ at the centre, we say the angle is (arc length) radians, so 360 degrees (the arc is the entire circumference)=2pi radians
https://www.youtube.com/watch?v=e7QjCL7lQM4&t=1091s, you can look at the "why radians" part of this vid
also you can look up about radians on chrome or yt for more vids
Get better at trig and so much more math at https://brilliant.org/TreforBazett to get started for free for 30 days, and to get 20% off an annual premium subscription!
This video is all about trigonometry, focusing on reviewing everything you are likely to actually use regularly in calculus. Instead of having to memorize a million trig identitie...
ignore the later half of the vid, you dont really need those formulas rn
LOL
Man I personally needed help with Ray Optics🥀😔
Are you familiar with the topic
ncert?
Yes
You see i am preparing for JEE
idk if i can help much cuz im in chapter cuz my coaching is currently in that chap
LOL
we can crack our heads togeather in dms if u want
Lol you in the same boat you mean?
i mean i can understand it
but the chap isnt finished yet
I haven't really started with it tbh, but I know the 10th part well
i mean i studied the ncert part for a exam and did well
Cool
Where u from
pretty obvious which country im from but i dont wanna talk about where exctly in a help channel here 😭
we can move to dms if u wanna talk
I understand 😭
or not no pressure
Sure idm
btw if you want problem sheets related to radians you should be able to find them by searching online
sure thanks
are you free
sry about us lmao
yea, you can ping or dm me
whichever you feel more comfortable with
mmh I’ll, ping
unlesss the channel gets taken by another person then ill dm
sounds good
!!
idk much about how the help channels here work im not 100% sure if your alowed to just keep it up
i think it closes itself after a period of inactivity
you can reopen one later and ping me if that happens
Thanks
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The rays are how far apart? How many degrees? Can you recognise that?
wym red or blue
does your class take arguments from 0 to 2pi or from -pi to pi
Btw this would be an angle in the first quadrant, whereas z2 lives in the 4th
-5pi/12…?
im not sure
this is how they calculated iz2
Yes
You have to be sure about this though
do you have any class materials from when you were introduced to argument
ok thanks
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its obviously just yes right?
actually maybe not
Yes.
im having a hard time understand why it must be trhe
Intuitively?
When you intersect more sets, you get something smaller or equal because you’re imposing more conditions for membership. Since I includes all of J, the intersection over I includes more sets in the intersection, so it can only get smaller or equal to the intersection over J
Pick something from the left
Then it is in every A_I
If you then pick a subset of these I’s all of them should (and does) still have the something
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With quadric equations, I’m finding “x” using the delta solutions because the whole equation isn’t solvable otherwise using the regular algebra rules?
by "finding x using the delta solutions" do you mean the quadiatic equation?
For example here what method would you guys use here?
Yea
well the quadratic equasions can be derrived using the rules of algebra
but somewhere along the derrivation you end up assuming b^2-4ac isnt negative if x is a real number
however, when we consider complex numbers, the quadratic formula can give you the answer for any equasion, just that the equations where b^2-4ac is negative have complex solutions
x(x-4)=0
so x=0 or x-4=0 which implies x=4
so x=0 or x=4
the derrivation of the quadratic quasion uses a method called "completing the square" which can also be done on any quadratic
since the square root function is only defined when the thing inside it is positive, then you can see how the derrivation assumes (b^2-4ac)/4a^2 is positive, but since 4a^2 is always positive, we only need b^2-4c to be positive
for square roots to be defined for negative values, you need the coples numbers
But I can’t use delta method here
Because I don’t have “c”
Here once again I need to use another method of solving cause i don’t have “b”….
So there are 3 ways of solving quadric equations
b=0
you can, c=0
yes, not directly, you have to do something called "completing the square"
remember a^2+b^2+2ab=(a+b)^2?
But what’s the ultimate goal for quadric equations? To know what the x is that leads to 0?
consider a quadratic expression ax^2+bx+c
different values of x give you different answers, (you can use desmos to see its graph)
the quadratic equation tells you when this equals 0 (or graphically, when the graph touches the x axis)
so yes, it is to find out what x implies ax^2+bx+c equates to 0
do you want to try using completing the square on one of your problems where a,b,c !=0?
its actually quite useful to know
allows you to express the quadratic in a more useful way in some contexts
(like solving integrals for example, but you dont have to worry about that for now)
But why can’t we solve x?
How
you have to use, a^2+b^2+2ab=(a+b)^2
to bring your equasion in the from of kx^2+n=0
though how exactly you do this is usually directly just told to you, you can try to give it some thought atleast
clue is that you try to add and subtract a number
its the same this as adding a 0
or just tell me u just want the method
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Let $(Y_n)$ be a sequence of i.i.d. real random variables with a symmetric distribution (i.e. $Y_n$ has the same law as $-Y_n$). Assume that $\frac1{n}(Y_1+\cdots+Y_n)$ has the same distribution as $Y_1$, for every $n$. Show that $Y_n$ follows a Cauchy distribution.\
Using properties of characteristic functions (cf), where $\phi$ is the cf of $Y_i$, I arrive at the functional equation $$[\phi(t/n)]^n = \phi(t)\quad\forall t\in\mathbb{R}$$Clearly $e^{|t|}$ satisfies this, which is the cf of the standard Cauchy distribution. But is it the only one? (Also, $\phi$ is a real-valued function.)
psie
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need help with this
Why e on top?
When its sum a*r^n
Here you have e^cn which is (e^c)^n
"a" would be 1
in fact a is the first term of the sum which is 1 here
hi
ohhhhhhhh
o h h h h
Except this it should work
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<@&268886789983436800> castrate this guy
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thank you
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hi im stuck where do i start with this
use equations to describe the problem:
- what does P being on the curve y=sqrt(x) mean in terms of its coordinates
- closest implies you want to minimise the distance
yea i understand that part
im just stuck on the approach
i feel like its smth to do with a triangle
what have you done so far
do you know pythagorean theorem
well it's the same
do u just extend a line downwards and then conntect p to 4,0 to make a rat?
yes
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can you check if i math this correctly
@twin wing Has your question been resolved?
I mean 0.00031 m is a lot smaller than 1 cm, so I doubt this is correct.
@twin wing Has your question been resolved?
From what I know of physics, Intensity is inversely proportional to square of distance between point source to that point
In this case
But youve taken it to be directly proportional
@twin wing
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I'm trying to understand a Pythagorean Triangle problem using the Speed of Light in one second (299792458m) as leg A, and the Plank Length (1.61 * 10^-35m) as leg B. Every time I calculate it in C++ using boost there's no difference in the hypotenuse and leg A. Does the triangle break at one point at certain lengths?
no, pythagorean always holds true
you're hitting the limits of precision though
how much comp sci do you know
Not much, just getting started in community college.
to answer your question directly, math on a computer with very small and very big numbers is usually error-prone
you might look into how a computer stores numbers
idk what types youre using here
Okay, I'll try something else. Also taking the inverse cosines of the angles posits one angle to be 90 degrees in at the end of the B side. I think I found something but just want to actually test it.
So it becomes a 90, 90, really small degree angle.
youre bumping against a common problem in computing so its probably worth exploring if youre curious
Okay, thanks man. Just seeing if I was losing my mind about the triangle always holding.
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Computers need to store real-numbered values, but how do they do it? There are multiple choices for how we could represent real-numbered values, but the floating-point representation standardized in IEEE 754 is the most common choice. Here, we explore how that representation works, the difference between single- and double-precision values, and ...
sure, no problem 
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omg i never responded to this. thats why my math seems wrong.
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for part b, how am i supposed to find the two vectors that i need to find the angle between?
from the position vector r
the only time dependent component gives you the velocity here (v = dr/dt)
and that has a vector direction of [40, -100, 0]
and while descending, you know the z component is additionally -16km/h, so the new vector becomes
original velocity + [0, 0, -16]
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midpoint of OH , right
correct
only takes 3 days to respond sadly
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trying to solve using mathematical induction. I know this isn't the way to do it however I think I'm still proving it (?). I'm asking for help on how to properly use inductions to prove this
take base case n=1
assume it holds for n=k
use that to prove that it must hold for n=k+1
$6^{n+1}-1 = 6^{n+1}-6+5=6[6^n-1]+5$
Donkey
honestly I see how to get to the second part after the first = but I'm unsure how the -6+5 becomes the last thing there
you take 6 common from the first two terms
factor out 6 from 6^{n+1}-6, leave 5 untouched
ohh omg that makes sense sorry if that's dumb I really didn't know how to get there but after I do get there how do I match it w the hypothesis?
ok, what's your induction hypothesis?
$6^{k}-1=5t
not sure how to use the image bot
⃟
so you js substitute that in the last part of this expression
$6[6^k-1]+5 = 6(5t)+5$
Donkey
and that's done
can I know how the that above 6(5t)+5 is proving?
the core idea of induction is that you prove a base case, make an assumption abt it holding for some random integer k, and prove that if it holds for k, it must hold for k+1
so the thing where we substituted $6^k-1=5t$ is us implementing the "if it holds for k" condition
Donkey
the remaining part is js taking 5 common, so $6(5t)+5=5(6t+1)$ which is clearly divisible by 5
Donkey
how is $6(5t)+5$ resulting in that? or is that the other side of the equation originally?
⃟
factor out 5 from both terms
ohh I see it now thank you sm for your help with this
np
are you a math major perchance?
oh I see you seem very good at it
thanks
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In EDA should you do analysis first and then clean the data or the other way around
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hola
maybe you should start by finding the solutions to those inequalities
got the intervals of x yes
what are those intervals
9/4 to 25/4
okay
so just transform the middle part of that expression to |x - 4|
what do you think the first step is?
we need to use inf and lamda that minimizes it
i need to understand in this form
A general tip I'd suggest for something like this is try to find an equality relating |x-4| to |\sqrt{x}-2|
and then using restriction on lambda to find x?
I mean okay, first can you find the equality I hinted at
yes wair
i think i should read the chapter once
okay so that's not what I was thinking
what I'm thinking is
[ |x-4|= |\sqrt{x}+2| |\sqrt{x}-2|]
lance lance
So like do you know geometrically @bronze grove what |x-4| represents?
yepp
what is it?
no like not as a shape
what is the geometric interpretation of the number |x-4|
if I fix a value of x
like on a graph?
no
i don't understand what u want me to do 😭
yes
if I tell you a value of x
like if x is 1
what does |x-4| mean
then its 3
Okay and what does that 3 mean
mod of the number?
almost
the point is that |x-4| is the distance between x and 4 right
a number? 😭
So if I tell you |x-4|<1, that means the distance between x and 4 is at most 1
so what values can x be then?
3 and 5
well between 3 and 5
so circling back to this
you then know that sqrt{x} is between what two numbers?
And basically the game we play here is we go

\begin{align*}
|\sqrt{x}-2| &<\varepsilon \
\implies |\sqrt{x}-2| \cdot |\sqrt{x}+2| &< \varepsilon \cdot |\sqrt{x}+2| \
\implies |x-4| &< \varepsilon |\sqrt{x}+2|
\end{align*}
and what you need to convince yourself of is
we can go backwards
lance lance
So if we start off by already saying |x-4| < 1, then we know that |\sqrt{x}+2|< \sqrt{5}+2, which we'll round to 5
So we can then say that
our condition will be $ |x-4| < \mathrm{min}( 5\varepsilon, 1)$
huh
anyway
our condition will be $|x-4| < \mathrm{min}( 5\varepsilon, 1)$
vie
convince yourself now that using this we can go backwards to get |\sqrt{x}-2|<\varepsilon
gotcha
Because if |x-4|<1 then
$|\sqrt{x}+2|<5$
lance lance
No worries :)
i think i will try to conclude myself
tysmm
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Hi im a 9th grader can someone help me explain how do i get the 8 in front of the (y-2) photomath gives me that buti dont understand tbst step
,rccw
Got that math teachwr handwriting already, keep it up.
Think of it this way, what did we factor out of the first parenthesis
$2y - 4 = 2(y - 2)$ and $4y^2 + 8y + 16 = 4(y^2 + 2y + 4)$
south
im new to this terminology what does factor out mean
8(y³-8)
or (2y-4)(4y²+8y+16)
(2y-4) can take out 2, and (4y²+8y+16) you can take out 4
Ok, how much of the problem do you understand?
oh so basically i divide the first one by 2 and the second one by 4 and thats like multiplying both by 8?
Walk be through your steps
to the part where i get 8 in front
and so basically thats like multiplying everything by 8?
Yes, we factor out 2 and 4, and since the parentheses are being multiplied we just multiply the factors and we get 8
it all makes sense now, thanks
Np
is that supposed to be good or bad
because my actual notebook is way worse
everything is so messy
Uhh, dont even worry about it, my physics homework is terrible
the only nitpick I can see about the handwriting is the possibility of misreading the 4 for an a, but that should be highly unlikely.
Terrible
still better than me
i gave a really god example there
with the picture
this is new - writing in mixed case.
I'd cry if I were your TA
I genuinely could not read what i wrote myself
There is 20 more pages
it is readable but it's just annoying to read
does someone understand 18.b we wrote a pop quiz that wasnt for grade and i got 0/10 from this part
ah, it's a difference of two squares
because $2^2 (ab + 1)^2 = [2(ab + 1)]^2$
south
I really need to learn latex goddamn
can you first write it as a product of two brackets?
and it has quite a few steps i believe
you mean am i smart enough to do it?
Smart≠good at math
or you could write $x^2 - y^2$ first and factor that
im sorry i dont understand the question
south
I believe it's to fully factorise all these expressions
so you keep factorising until there's nothing left to factorise
okay, can you factor this?
right! so the idea is with $[2(ab + 1)]^2 - (4a + b)^2$
south
we use $x = 2(ab + 1)$ and $y = 4a + b$
south
sub those in
wait i dont understand what text should i look at
Its a bit unintuitive to go straight to factors when youre new to it. I reckon we should expand the squares
sub those into (x + y)(x - y)
if i square the first part, doesnt that make it 4 a2b2+ 2ab+1?
8ab
like doesnt it square the whole thing?
that's going in the wrong direction
because what you're doing is trying to expand that
I mean its more intuitive for ninth graders
Expand the squares, sum them, factor
you're missing brackets but 4(a^2 b^2 + 2ab + 1) is correct
i think i should learn english math terminology so i can understand what yall saying
no, that's even harder
this is absolutely a difference of 2 squares exercise
Just expanding the squares, summing like terms, and ABC formula?
oh wait i think i understand, im supposed to make it have 2 parts so i can do the x-y) (x+y
I bet they haven't learned how to factorise 4uv - 16u - v - 4 as (2u + ...)(2v - ..) or (4u + ...)(v - ..)
yep!
can you help me with 18.3
you want to get the multiplication of some brackets
because the parts in each bracket are simpler
but like dont give the answer immediately i mean its fine if you do
makes sense
if you can do 18.2 you can do 18.3
imma try
A^2-B^2=(A-B)(A+B)
you still need to sub those into (x + y)(x - y)
You remember the double negative rules?
your factorisation should be using a and b
like a-(-b)= a+b
++=+, +-=-, -+=-, —=+
actually you just need this
but it helps to be aware of similar rules
Odd number of lines and its negative, even number and its positive
i get to the step the first one where i have (x-y) squared (x+y) squared - (x+y) squared
Is this 18.3?
yeah
by 'sub', I mean find x, and replace it with 2(ab + 1)
every time you see x, replace it with 2(ab + 1)
no they're still on 18.2
I mean its the same problem essentially
Just different numbers
how do yall se that as the same thing
those 4 problems are all difference of squares problems
you use (x + y)(x - y) for all of them
what are you getting now?
you were close with your first idea
it's $[2(ab + 1) + (4a + b)][2(ab + 1) - (4a + b)]$
south
again, you should use brackets surrounding the y first (cause you need to subtract it)
then you can drop them later
Important to define what x and y is in this context
x = 2(ab + 1) and y = 4a + b to remind you
yeah, I see you're getting the idea for 18.3 too, but you're further off
imma try doing it again with the info you just gave me
to see if i get any closer or actually solve it
do not try and expand x^2 - y^2 or factor it just yet
it's substitute first then factor
i got it right but i pretty much guessed
like i didnt get it right because i completely understood it
Ok so think of it this way. We have two squares right?
We call one x and the other y.
If we want to find the difference between them, we have to do x^2 - y^2=(x+y)*(x-y)
First of all, lets do 18.3. What is x and y in that context?
youre asking me to compare it to 18.2?
do you see how you can get $(x^2 - y^2 + x + y)(x^2 - y^2 - x - y)$?
south
what should i answer first
x- x2 (btw when i put the 2 its because i cant find the squared) so basically x= (x2-y2)2 and y is -(x+y)2 if thats what you meant
actually without the squared at the end
Last page of your special symbols there should be ^
we use that to denote squared
So x^2
how to type it
Phone or pc?
pc
Look carefully on your keyboard for the upwards arrow, it varies with region
For me its next to enter
how is the szmbol called so i can google it
try 'caret'
no wait actually i have better solution
alr so is this correct
in 18.3
x- (x^2-y^2)
y- -(x+y)
no, the new y is (x + y)
no minus sign
oh yeah mb
otherwise that's correct
I hate how the names for the squares are the same as the factors
Just stick with a and b😭
yeah it's an abuse of notation to say that
so should i try to replace x with a and y with b and solve it like that
you'd need to say X = x^2 - y^2 and Y = x + y
yes
Write the equation now
Yup,
so im on the right track?
now you can expand the brackets, yes
wdym by expand
does that mean that you want the first part of the first bracket (a^2-b^2) to make it (a-b) (a+b)
that's what we need, yes!
so (a - b)(a + b) + (a + b)
and i do that for both parts or just the first
both parts
We do the first first and the second second
you need to factor both brackets
like this?
We should prolly collect like terms to avoid confusion before expanding tbh
yeah cuz from 1st to 8th grade everything was in italian and now 9th grade everything is in croatian so my terminology that i know is like split in half with italian and croatian and i know a bit of it in english
Math is math, the symbols may change but the methods stay the same
We usually do everything in the english alphabet, since its more international
wait so am i on the right track if you look at the last thing i wrote
correct, but you need to keep factoring both brackets
and how do i do that
(a + b)(a - b) + (a + b)(1), that's the same as the first, do you agree?
wait what
yeah thats the same
cuz anything multiplied by 1 is 1
i mean
that
by 1
is that
like x by 1 is x
Correct
my bad my fingers are faster than my brain
so you can factor this with (a + b) in common
wait i think i see what you mean
Ok, lets start with the first bracket step by step, [(a^2-b^2)+(a+b)]=[a^2-b^2+a+b] right?
yes
If we wanted to collect all the as together and the bs together how would we do that
With parenthesis
wait but then my last step was useless?
it's on the right track
keep going
yeah but my step and the one he showed me go in diffeent directions
i feel like his is more simple
Theyre both right
imma go with yours
I just prefer to collect like terms before expanding
What do we do next then?
If we want to collect as together and bs separate?
if i do that i get (a^2-b^2+a+b) (a^2-b^2-a-b)
, we cancel out the parenthesis?
But we want to keep them in brackets for now
(a^2-b^2+a+b) now what?
Dont dissolve the parenthesis
but thats what you did here
.
Yes, correct, its just better to do them separate😭
Since it avoids confusion
Lets start with grouping terms, (a^2-b^2+a+b) =[(a^2+a)-(b^2-b)] right?
yes
So now we have two parts. What can we do?
that's not how you fully factor it though
i can send u the way my teacher did it its way shorter but like way more complex
I mean we can just multiply after
i really have no idea dawg
a(a + 1) - b(b - 1) is not a valid factorisation
No, but a(a + 1) - b(b - 1) can be factored further
fair
should i?
Send it, it should result in the same thing
Wait are we going for a linear system or a factored system??
i have no idea waht you just said
the exercise says
rastavi na faktore which means decompose into factors
Classic vague maths
its just the way my professor did it i sent it here so maybe this is the way i should do it too
can you explain why he adds the -1^2 in the bracket?
cause $(a - b)^2 - (1)^2$ is another difference of squares
south
oh wait before that
Should be -(1^2) tbh
if you divide $(a - b)^2 (a + b)^2$ by $(a +b)^2$, you get $(a - b)^2$
south
now if you divide $(a + b)^2$ by $(a + b)^2$...
south
thats just 1?
@pliant shore Are we going for [a(a - 1) - b(b + 1)] * [a(a + 1) - b(b - 1)] or the linear form😭
Theyre both fully factored technically
no, a(a - 1) - b(b + 1) is not fully factored
cause that's not a product of brackets
indeed
Alr fair, only linear factors
i kinda understand now
I mean what your professor wrote is the solution 🙂
basically we got that for homework 2 weeks ago and someone asked if he could explain it which he didnt do he just solved the exercise without explaining
I do think that it should be -(1^2) rather than -1^2 but i guess its just semantics
Unfortunately it be like that, factorizing is just finding common factors and pulling them out
Its hard to explain
and even harder to understand
Pretty much, if it helps, consider factors to be a polynomial just divided up, whenever you have a group of factors you can go backwards and create a polynomial.
@pliant shore Gotta go, freezing my hands off writing this so imma go inside
yall so nice ty guys
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if a sequence diverges does that mean that every subsequence of it also diverges?
Think!
1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, ...
(-1)^n
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wut
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✅ Original question: #help-36 message
it's bounded but not convergent
yeah but also not divergent
dawg
look
we define divergent by not convergent
| a_n | < 2
yes
rlly?
it's bounded
but divergence means a_n > M for every positive M in R. or -M
no it doesn't
huhhhh
that's just the opposite of bounded
thats unbounded
oh i see
a sequence being bounded is not a sufficient condition of it converging
im not talking abt convergence
there is no such thing as a sequence neither converging or diverging
divergence is the literal negation of convergence
divergence. i thought if it doesnt converge to a point, but also doesnt diverge to infty, it doesnt diverge
no
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if it doesn't converge to a point, then it diverges, full stop
So you're looking for a monotone divergent sequence with convergent subsequence?
nono i was just asking
That's actually an interesting question though
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✅ Original question: #help-36 message
Yeah that makes sense
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Can I get help w question 3
ok, that's definitely a lot of threes running around
how far did you get on your own thus far
show your attempt and we can diagnose it
I don’t understand why
show your attempt so that we can see where and how you went wrong
ok i see two mistakes
the second of which is that 3x^(3+3+3) somehow had its x completely evaporate into nothing
actually no i see more mistakes
I multiplied
on the bottom, you have:
3 * x^3 * 3 * x^3 * 3 * x^3
there are three 3's in the product
those become 27, not just a single 3
why what
Does it multiply
remember that when a number and a letter stand next to each other in algebra, it means multiplication
$3x^3$ is really $3 \cdot x^3$, agree or disagree?
Yes
Ann
on the bottom, you have:
3 * x^3 * 3 * x^3 * 3 * x^3
or
3 * 3 * 3 * x^3 * x^3 * x^3
do you understand now what went on in the denominator
I still don’t get it
ok lets try to forget about that for a bit
here is a different expression
i want you to simplify this for me:
2a * 4a
Idk how to do it
again,
when two things are next to each other,
it means multiplication,
so 2a * 4a breaks down into 2 * a * 4 * a
understand?
Yes
multiplication is commutative,
so these factors can be written in any order you like,
for example as 2 * 4 * a * a
understand?
there's no kinda, you either understand what im talking about or you dont
Does it become 8a^2?
yes 8a^2 is correct
Ic
now can you do the same thing to 3x^3 * 3x^3 * 3x^3
x^3
don't miscopy the 3 exponents as 2's
you did that all three times 
also your fraction bar is way way too short and those x's are very sad in the rain
I’m sorry
I don’t know how to do the x
Ohh
So the 3 multiply
And the card
Add
X
Tysm
I still need help
ok, so what did you get in the denominator then
I got 27x^9
Can you tell me the rules for this
Bc it’s way different form what Ik
the rules for... what exactly
The question you helped me w
What Ik is same base and it’s multiplying means you add
i dont really know what "rules" i could possibly give you
that's the law a^x * a^y = a^(x+y)
but phrased in a wonky way
I don’t get it
i am taking the thing you're saying and rephrasing it with more proper wording.
im struggling to think of any rules that i could give you to memorize as mantras
cause like, idk
when a number and a letter stand next to each other in algebra, it means multiplication
thats the closest i can give you
you maybe need to go back to easier questions to repractice
I don’t have time
I have an exam tomorrow
And other thing to study
What about question 4
The guy in the video did 4.4^x as the denominator
when you add four of the same thing together, it is the same as multiplying that thing by 4
Yes
$a+a+a+a=4a$
Ann
no deep magic or mystery or arcane rule here

