#help-27
1 messages · Page 304 of 1
so for this diagram right
you have a function which can be represented on this graph
where if you plug a value of x into it you get a value for y
you can plot this point and for every point for the function and you get this graph
because this function is restricted
as in its not true for all values of x and y
you have to use inequalities to represent the values which are true
which part do you think is confusing?
or is it all a bit confusing
Dude honestly I’m a HUGE air head, it’s like I can hear what you’re saying, but I can’t understand most of what you’re saying because I can’t visualize it, and when I do understand it, it still feels like there is something I don’t understand.
thats honestly how i feel when i study at my level too
but thats the learning process
eventually with practice all of this stuff will seem a lot more intuitive
okay lets start from the beginning if you'll let me
Yes sir
okay so i think its important for me to understand where you are so i can explain this in a way that will be more intuitive to you
do you know what a function is?
Yes an equation that has in input and output
okay perfect
so in maths we like to have sets of things
basically
for every function
they will all have a set of inputs
and a set of outputs
for y = x +2
if your set of inputs is {1,2,3}
your set of outputs will be {3,4,5}
because the function tells you to take this set of inputs add 2 to them
and produce a set of outputs
am i making sense so far?
Can i help
up to caleb i guess
Let Hapus finish up and then you can share your knowledge
Ok
If you have anything to say about what Hapus says like a correction that would be helpful to both of us though
right so your domain is basically your set of inputs
and your range is your set of outputs
thats really all it is
Ok so that had a nice click to it
so lets clear up the bit about inequalities
lets say -5≤y≤5
all this tells the reader is the values that y can take
because they are ≤ and not <
you can include the numbers on either side
because y can also be equal to -5 and 5
so if i was going to only pick integers on -5≤y≤5
my set of numbers would be {-5,-4,-3,-2,-1,0,1,2,3,4,5}
if it was -5<y<5
{-4,-3,-2,-1,0,1,2,3,4}
because of the notation we are using
so i mentioned that this function represented by this graph was restricted
how so? well you see each end of this curve is cut off
so if i tried to plug in x = -6 into this function it wouldnt be defined
there would be no answer
because the function is restricted to values in an inequality
rather than being able to use all the numbers
this is what you're being asked to find in the question
for the first question at least
the values in which the outputs can take
something crucial to understand about functions when theyre graphs, is you still treat them like functions with inputs and outputs
except your inputs are the x values
and the outputs are the y values
if i plug in x = 0, what do you think the y value would be?
for the first one
its also fine to not be sure but try and guess anyway if thats the case
okay so unfortunately thats not correct but nice try
so this graph tells you what the function does
which is why graphs are so useful
if you look at the center of the graph
this is where x=0 and y = 0
so the y line is the one pointing upward and down
and the x line is the one pointing left and right
the numbers on this line are the values of x and y
at that particular point
so if i chose x= 0
lets call the function f
so f(0) = 2
this notation just means f(input) = output
or f(domain) = range
do you see the two in the middle of the curve
this is the point im refering to
yes only 1 for now
Yes in the middle is C and sorta of B
so this cross right
almost looks like crosshairs
the horizontal line is your values of x
and the verticle line is your values of y right
have you done coordinates?
like could you point to (1,1)
Yes
cool
so the values where x = 0
i.e (0,0) or (0,1) or (0,-1)
this all forms a line right
a verticle line
its actually the same as the verticle line i pointed out earlier
every point on that verticle line is where x = 0
similarly every point on the horizontal line is y = 0
you can check this using coordinates
so if i wanted to find (0,-6) on this diagram
it sits on this line
same for (0,6)
in fact as long as the left number in the coordinate is 0 or x = 0, this will always be the case
let me know where you're stuck if you are stuck
if you ask me a question about anything ive said so far ill try my best to explain
its just slightly difficult to do this without drawing my own diagram
still there mate?
Yes
im going to try and draw my own diagram and ill send it to the chat when its done
Ok
sorry the internet didnt work on my phone had to use data lol
does this help?
its fine if it doesnt yet. i can explain why i drew it this way
its also slightly incorrect but its correct in the ways that matter for this question
its a lot wider than its supposed to be lol
because the value of y for every point on the x axis is 0
the x axis you could say is the line where y = 0
vice versa for the y axis ( line where x = 0)
so what inequalitys tell you is the nature of this restriction
(how is it actually restricted, which points is it restricted between)
Ohh ok
The reason both of them have all points be 0 for the other is because there are restrictions
the axis?
its the function which is restricted
okay lets take another example
for this example y = x+2
if i restrict y
-1≤y≤1
lets say
this means the y on the left can only range between the values -1 and 1
this will inherantly limit which values of x can make this condition true
so for y = -1 x must be -3
and y = 1 , x must be -1
so the range would be -1≤y≤1
the domain would be -3≤x≤-1
its easier to see it the other way around
so y = x -1
if we say
our domain is 1≤x≤7
this is the same as {1,2,3,4,5,6,7}
as we said earlier
this is all the possible values x can take
if we take the end points and put them through our function we can find the range of values for y
can you find the range of this function given this restricted domain?
either an inequality in terms of y or a set of numbers will do fine
let me just clarify the question
our set of inputs is {1,2,3,4,5,6,7} = x
our function is y = x -1
whats our set of outputs
do you want me to explain?
Yes please
ill explain why this is useful to our example in a second
so our function is y = x -1
this tells us that the output is the input -1
so if we give our function a set of inputs to work through
all we do is subtract 1 from each of the inputs
to get our range
so our inputs are x = {1,2,3,4,5,6,7}
our function transforms those numbers
using y = x -1
to y = {0,1,2,3,4,5,6}
we subtract 1 from each of these numbers in the input set
if we did this for one point
lets say x = {1}
y = 1 -1
so y = 0
the same thing is happening with the inequalities
so x = {1,2,3,4,5,6,7} is the same as 1≤x≤7 (inputs or domain)
and y = {0,1,2,3,4,5,6} is the same as 0≤y≤6 (outputs or range)
so lets put this a different way perhaps it might help
im going to ask you some questions about this curve in 1
Okay
what is the largest value of y this curve can take
so look at the y axis
maybe draw a line from the y axis to the highest point of the curve
Yes
the y axis tells us how high or low we are
x axis tells us how far left or right we are
im sure u know that
just being sure
so if you draw a line from the very top of the curve
horizontally to the y axis
what number would it say at the y axis
7
-7
nice
so that will be the range of values your function can give
or just the range
everything between those points
So the answer is A
we are only talking about y here
y is our outputs remember
and outputs are the range
so -7≤y≤7
is our range
because our function cannot go outside this inequality
Ohh I see what I did wrong
okay what would be the domain of this function
7
itll be the same thing you did for the y values
but the x
cause now we focus on the inputs
x is always inputs
y is always outputs
whys that?
To find the domain do I go to the lowest point for the x axis?
Yea I’m lost
thats okay
let me do a simpler curve
and explain where the domain and range come from
then we can come back to this curve and do the same
Ok
again the graph is dodgey but it represents the idea that we need
but yeah, key points are. domain is a fancy word for set of inputs, and range is a fancy word for set of outputs
so the two coordinates in the bottom left and bottom right
are our maximum and minimum points of this curve
its a line but im going to call it a curve
so our minimum is (-6,-7)
so minimum of x is -6 and minimum of y is -7
similiarly our maximum is (8,7)
so our maximum for x is 8, and maximum of y is 7
so to find our domain for this
we take max and min of x
which is -6 and 8
and our max and min for y
which is -7 and 7
so we can write and inequality for each
which tells us
i can pick any value between -6 and 8 for x (or more formally -6 ≤ x ≤ 8) for the domain
i can also pick any value between -7 and 7 for y (or more formally -7 ≤ y ≤ 7) for the range
this tells us the values that the function is defined for
which is useful
because if someone tried to plug y = 8 into our function we wouldnt have a definition at that point for the curve
so we gotta tell them, just use these values (-7 ≤ y ≤ 7)
does this make sense?
Yes it does
nice!
Though it’s hard to pick up on every single detail I got the jest of what you’re saying
i can try keep it brief from here on then
you can look back on my drawings or messages to help
can you explain briefly why A is the correct answer here?
Ok
On the highest point for A the range for that is 7 because A is at the point of 7
The - 7 is at the point of E where that is the lowest point of the curve
You said this sign with the < like at the bottom means it’s either equal or less than
-7 is less than 7 while the 7 is greater which explains why there are two of the same signs and the y is the output
its a good answer actually
but
we can simplify it
shall i tell you how id justify A Being correct
Yes sir
the highest point the function can take is at A, and the lowest point is at E.
the y coordinate at A is 7 and the y coordinate at E is -7, the function only covers values between these two extreme points. so the range of the function must be -7 ≤ y ≤ 7
id say this answers the question well because in mathematics we like to keep to definitions
Yes that was way better
we could define a range to be all the points which the function can output
and the domain to be all the points we can input into the function to get an output
there is no number i can input into the function to get a bigger output than 7
its the same for -7
okay could you tell me what the domain is?
≤
here is the symbol if you want to copy it
(remember its the same as how we find the range but for x values(input values).)
i can give u a hint if you get stuck
Wait I’m confused
okay so
the domain will look like this a≤x≤b, where a is the minimum x value and b is the maximum
so your minimum x value will still be at A
instead of looking up and down
we are now looking left and right
where left is minimum and right is maximum
also side note lol
question 2 on ur paper is wrong
if you wanna get really mathematical about it, its not rigorous enough at all
still there dude?
dw mate i got nothing better to do rn
@sour shard Has your question been resolved?
Sorry I’m back
I did a group pizza project with my aunt and little bro
hi
Hello
sorry dude i gotta go unfortunately
gotta cook dinner and wind down
im sure if u ping the helpers someone will come and help you out
sorry dude
No worries man thank you so much for your time and effort in helping
I’m really thankful you helped
ur welcom bro
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<@&268886789983436800>
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hello can someone help ?
what have your tried?
wait ill take a pic
i actually tried this and it didnt work
it was like a loop i keep doing the same shit idk whats wrong
what course are you in?
mechanical eng
no like what class
its called Hidva idk if u call it the same
its all about limits
and lopital
and integrals
Have you tried substitution? I think that might work
consider stuff like liate,
where you usually want to differentiate the power component
and also take note of what e^x^2 differentiated to
and choose a more appropriate v' and u
hint: ||x^3 = x^2 * x||
uff
that shit is impressive
u sub should work better
not really
Looks shorter to me if you do u-sub then partial integration
i mean no harm trying
you'd end up having to do ibp anyway
do u think this would work ?
yeh, that should work
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938c2cc0dcc05f2b68c4287040cfcf71
What have you tried so far?
I was looking for help on how to start
Oh okay
Getting the matrix representation of f would be a good start
Then if you recall
det(A - L I) = 0 when L is an eigenvalue of A (I is the identity matrix)
,, M_{BB} = \begin{pmatrix} 2 & 1 & 1 \ 0 & 2 & 1 \ k & 0 & -5 \end{pmatrix}
,w transpose {{2,0,k},{1,2,0},{1,1,-5}}
Yeah haha
938c2cc0dcc05f2b68c4287040cfcf71
so?
^
ok
You can sub L = 3 before taking the determinant as well
,w det {{2-L,1,1},{0,2-L,1},{k,0,-5-L}} = 0 where L = 3
gnarly
could just do row reduction and find what value(s) of k give you a nontrivial solution
Yeah
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So, basically my teacher has given the theorem lim x->p f(x) = lim x->p g(x), however, he doesn't explained how I was supposed to find g(x), if anyone could help I would be grateful. (I tried L'Hopital btw, still didn't work.)
what happens if plug in x=-2 in the top and bottom
0/0
l'hopital should work
It still gives 0/0 tho
g(x) could be anything, depends on the theorem
Then use L'Hopital again
Repeat till it no longer gives 0/0
I can? (I just started calculus I, so I have no idea.)
Yes, as long as you verify your steps with us
So, it's just (-2x - 1)/(x - 2)
Did you get answer?
L'Hopital gives me -24/-16 (If I didn't miss), and the correct answer is -3/4
You probably did a mistake
Lemme redo, holdon
Also, answer is -3/4
Yeah, I just did the math with 2 instead of -2 🤡 , it worked tho
Ty guys for the help
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I'm confused as to what this is asking me to do. I have been able to fill in the first few cells involving P(X=x | p=0.05/0.1/0.2) but without the actual value for P(p=0.05/0.1/0.2) how am I supposed to be able to fill in the rest?
I found the P(X=x | p=0.05/0.1/0.2) values with the geometric distribution formula p*(1-p)^(x-1)
<@&268886789983436800>
@late cedar Has your question been resolved?
@late cedar Has your question been resolved?
@late cedar Has your question been resolved?
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I think most of its right and would like someone to confirm
(sorry for the handwriting)
It doesnt seem like you fully simplified #1
Thanks
is that $8+(2x+1)7$?
;(
Which problem
For #1.
Yea
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should i prove this using induction? ive found that theres a cyclic result in the remainders of 3,9,1
What exactly is the cyclic result?
And if there is one, induction is probably the way, though you could use casework here.
just from doing the first few
$3^1 \equiv 3 \mod 13
3^2 \equiv 9 \mod 13
3^3 \equiv 1 \mod 13$
and it repeats the 3,9,1 as u increase the exponent
oh me when backslashes on discord
jess
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so what exactly would my 3 cases be? i had $3^n \equiv 3 \mod 13$ if $n \equiv1\mod 3$ for the first case
jess
$n=3k+1$, $n=3k+2$, $n=3k+3$.
;(
Since you said it yourself, it repeats.
@last tartan Has your question been resolved?
why +1,2,3 instead of 0,1,2?
this looks like it starts with k = 0
and then you always add 3
could you elaborate?
i have
$3^k\equiv 1 (mod 13) \text{ when } k\equiv0 (mod 3)
3^k\equiv 3 (mod 13) \text{ when } k\equiv1 (mod 3)
3^k\equiv 9 (mod 13)\text{ when } k\equiv 2 (mod 3)$
i don't fully understand how to prove this for all n+1
jess
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You got 3 cases for $n \in \mbb{N}.\$
Suppose $k \in \mbb{N}_0.\$
The first case is $n = 3k+1$ which means $3^{3k+1} \equiv 3 \pmod {13}.\$
Then the second case is $n = 3k+2$ which means $3^{3k+2} \equiv 9 \pmod {13}.\$
Then the third case is $n = 3k+3$ which means $3^{3k+3} \equiv 1 \pmod {13}.\$
All three cases cover each eventuality of $n$ so you would be done.
Notice 3^(3k+3) = 3^(3k)
As said, I think the reason he chose 3k+3 is because k starts with 0, so wih 3^(3k) you would have first 3^0 but n starts with 1
but that's a technicality
You can write your answer as a piece wise function
3^(3k+3) = 3^(3k) mod 13 right
- 1 mod 13? not congruent?
use \ to remove the dot
so for the first case
$3^{3k+1} \equiv 3 \pmod{13}$
i can simplify that to
$3^{3k} * 3^{1} \equiv 3\pmod{13}$
so then how can i use the previous facts we established?
I would just leave it as it is
jess
so for case 2 i can do the same
$ 3^{3k+2} \equiv 9 \pmod {13}$
rewrite as
$3^{3k} \cdot 3^{2} \equiv 9 \pmod {13}$
and same for 3
jess
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im back
t⁴ = 1 or 0 mod 5
how did you come to that conclusion>
see numbers from 1 through 9
just try t=0, t=1, t=2 and so on and see the loop
Yeah exactly
so you're saying to compute
$0 \equiv 0 \pmod{5}$
jess
what
im lawst
it’s easier to work with squares first
1^2 = 1 mod 5
2^2 = 4 mod 5
3^2 = 4 mod 5
4^2 = 1 mod 5
5^2 = 0 mod 5
6^2 = 1 mod 5
7^2 = 4 mod 5
8^2 = 4 mod 5
9^2 = 1 mod 5
how do we relate that to ^4?
square both sides
so its just all either 1 or 0 after squaring both sides
yep because the 4 mod 5 ones become 1 and the 1s and 0s stay the same
so that means a^4 , b^4, c^4 their sums are either 0,1,2,3 mod 5
therefore never congruent 4 mod 5
hot thank u
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,rotate
can someone help me figure out this question? i dont understand the way its worded
plus im not the best at this kinda math
Dyk where the third quadrant is?
yeah
In the third quadrant:
x is pos/neg?
y is pos/neg?
x is neg, y is neg
,tex $+$
King Leo
yeah…? like do i understand the line is in the third quadrant?
Ok
Can you draw a right triangle that includes
- the hypotenuse as the green line
and which horizontal leg stemming from the origin touches this triangle
I gtg
,rotate
were you given a formula sheet?
i wont have one for the test, but i can give you all the ones they taught us
do you know double angle identities
i dont know the names, but if you write one out, i could give you the other two probably
one sec
like if you give cos, i could give you sin and tan
do you know these
sin, yeah
cos, still getting the memorizing part down, but i got a general idea
tan, hell nah
its really just these identities that are the hardest ones that i dont know yet tho
now that is the basic bit
you can now pick like the sin one plug everything in then do that with one of the cos ones then the tan one
do you get it?
if you want I can solve a part for you as an example
@chrome vault Has your question been resolved?
oop sorry didnt see ur msg
oooooh shit i get it now
i didnt even think to use those identities for triangle problems
tysm 🙏🙏🙏
np
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hello :)
i'm trying to solve and equation
i need the intersection of a line
and a torus
defined by the red equation
before i try to solve it
i would like to know if it's a solvable equation
i know it's a quartic
In case u dont have desmos and dont want to waste ur time?
Like with desmos, u only need to see if the line cross the torus
no i need to find an equation
If it does cross, the its a solvable equation
i need to be able to find the solution analytically
it's for my code
i'm making a torus planet and i need the entry and exit points
to make the atmosphere
so i get an arbitrary vector and origin
for each pixel
and then
Then trying to solve it, if there's no possible output, then its unsolvable
i have a, b, and c as the radii of the torus
i know solving it will take a very longt time
so im wondering if it's solvable analytically
The easiest way I could think of is
compute the shortest distance d from the line to the torus center C
If d > R +r, the line cannot intersect the torus, and you can skip the expensive check
U can imagine the R + r is just the radius for a sphere that would enclose ur torus
Bruh
if it's possible to get the whole equation
If the shortest distance from the line > than the R + r; then its not solvable
i'm not asking if there's a real solution
i'm asking if the equation is able to be solved in terms of t
idk then, pretty sure the only way to know its solvable or not is just to solve it ig
@clear geode Has your question been resolved?
ok so
i tried to solve the equation
and i'm left with this
do i have to
substitute the x, y, and z values into the function?
that will make a lot of terms
@clear geode Has your question been resolved?
if the line stays at the origin it becomes a 2d problem that should be fine, otherwise I assume it's really ugly. there's a formula in section 2 here https://arxiv.org/pdf/2301.03191, or you can use something like z3 in python I think?
ok but
the line being at the origin doesnt allow for ray tracing
wait a sec
yea anything off-origin is basically working with ellipses which always suck
i just had an idea
what if
i get the equation for a ring
and then
seth the equation to be
(ring equation) = (thickness of torus)
and then solve

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Is this considered a "clear" proof or would it benefit more with steps shown?
Let $\phi(\cdot)$ be the p.d.f of $\mathcal{N}(0,1),$ i.e. $\phi(t) = \frac{1}{\sqrt{2\pi}} e^{-\frac{t^2}{2}}$. For any $u \geq 0$, let $\Phi(u) := \int_{t \geq u} \phi (t) dt$ be the c.d.f
\ \
Prove the following bounds for all $u \geq 0$
[
\bigg (\frac{1}{u} - \frac{1}{u^3} \bigg) \phi(u) \leq \Phi(u) \leq \frac{1}{u}\phi(u)
]
\begin{proof} To obtain the upper bound, integration by parts is necessary.
[
\Phi(u) = \int_u^\infty \phi (t) dt = \int_u^\infty \frac{1}{t}(t\phi (t)) dt \hspace{2em}
\begin{tabular}{c|c}
\textbf{D} & \textbf{I} \ \hline
$1/t$ & $t\phi(t)$ \
$-1/t^2$ & $-\phi(t)$ \
\end{tabular}
]
[
\implies -\frac{1}{t}\phi(t)\bigg]u^\infty - \underbrace{\int_u^\infty \frac{1}{t^2}\phi(t) dt}{\geq \ 0, \ \forall \ u\geq 0} \leq \underbrace{\lim_{t\rightarrow\infty}\bigg(-\frac{1}{t}\phi(t)\bigg)}_{= \ 0} - \bigg(-\frac{1}{u}\phi(u)\bigg) = \frac{1}{u}\phi(u)
]
[
\implies \ \Phi(u) \leq \frac{1}{u}\phi(u)
]
To obtain the lower bound, another iteration of integration by parts on the remaining integral is necessary.
[
\int_u^\infty -\frac{1}{t^2}\phi(t)dt = \int_u^\infty -\frac{1}{t^3}(t\phi(t))dt \hspace{2em}
\begin{tabular}{c|c}
\textbf{D} & \textbf{I} \ \hline
$-1/t^3$ & $t\phi(t)$ \
$1/t^4$ & $-\phi(t)$ \
\end{tabular}
]
[
\implies \frac{1}{t^3}\phi(t) \bigg]u^\infty + \underbrace{\int_u^\infty \frac{1}{t^4}\phi(t)dt}{\geq \ 0, \ \forall \ u\geq 0} \geq \underbrace{\lim_{t\rightarrow\infty}\bigg(\frac{1}{t^3}\phi(t)\bigg)}_{= \ 0} - \bigg(\frac{1}{u^3}\phi(u)\bigg) = -\frac{1}{u^3}\phi(u)
]
[
\implies \ \Phi(u) \geq \bigg(\frac{1}{u} - \frac{1}{u^3}\bigg)\phi(u)
]
Combining the upper and lower bound gives the final bound as follows
[
\bigg (\frac{1}{u} - \frac{1}{u^3} \bigg) \phi(u) \leq \Phi(u) \leq \frac{1}{u}\phi(u)
]
\end{proof}
cameron
I ask if this is clear because I have been getting mixed answers from different people and I want to know if anyone else had their own thoughts
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How do you diagonalize a matrix?
I know that i have to find the eigenvalues
Then do Ax = λx
So (A-λ)x = 0
This is the part i have a problem with
Its kind of tedious to do this line
My calculator simply tells me infinite solutions, how do i find a set of (x,y,z) that satisfies (A-λ)x = 0 quickly
Yes, you need the characteristic polynomial
find its roots to get the eigenvalues
for each eigenvalue solve (A-lambda)x = 0 to get the eigenvectors (or eigenspaces)
yes
how do i solve it?
is there a fast way
hm at this point you can probably only use regular quick methods like Gauss
assuming you try to calculate it by hand
yes i have to sadly
you don't need eigenvalues to diagonalize
do i have to make one row (0, 0, 0)
What really
wdym
for Gauss you solve for the staircase form
which is pretty quick
^^
gaussian elimination?
yes
do you mind giving an example of what i should make it look like please?
thank you
Look at the first column of the matrix, find the least common multiple of those numbers, multiply all the rows so that the first entry is the LCM, subtract first row from all other rows, rinse and repeat for the submatrix
probably faster to watch the process online :D
but if you've seen the process before
then you can take this as reminder
getting all 0's below the diagonal column-wise, and then 0's above the diagonal row-wise
damn that's quite some work lol
sure
after doing gauss a few times, it probably only takes about a minute though
i see, thank you
@strange arch this can be done WITHOUT gauss?
the marking scheme's method uses 3x3 determinant
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@granite arch Has your question been resolved?
Did you do the first question ?
@granite arch Has your question been resolved?
yes
I don’t really understand your question. This looks solved without gauss
But i don't get the steps
I want an explanation for it
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hi! could someone please explain how to do this, im so confuzzled. thank youuu
try writing sec and csc in terms of cos and sin
yes
so sec (theta) = 5 , which means it would equal cos (theta) = 1/5 ??
i got cos, csc is the one im struggling with
find sin
yes lol, ppl said i looked like her in that pic
so i just kept it
its been there even since i got discord
lmao
youre the first person that actually asked me
damn
i also meant damn in a good way
yes, and then you'll need to use the knowledge of your quadrant to determine the sign of sin
that pfp looks like an old friend of mine from my cell bio class, but that was a million years ago
damn bro you were in there with a madison beer lookalike?
🤝🏻
madison beer?
yea she’s famous, it’s the girl in her pfp
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Can someone check these
,w 4((-(xxxx + 2xx + 3)^(-2))/2) = integral of ((xxx + x)/(xxxx + 2xx + 3))
Is it right?
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How would i solve this im confused
What type of geometry is this bro
It's not congruent
What is it asking for
its asking for x
x is not a point
its intersection of ca and eb
bro what how will you solve for a point
the angle

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Is the math and sig figs correct on this
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<@&286206848099549185>
@blazing juniper Has your question been resolved?
Depends on what your teacher wants
In my syallbus final answer is given to 3s.f with 5s.f for intermediate steps
But this differs for country to country
In this case you get exact values though so maybe you don't need to round using sig fig
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wut
/reopen
open a new channel
oh mah bad bro
this wont reopen
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I don't understand smth max area yea we differentiate it to get max area
But why can't use take max amplitude of sin and cos =1 and solve for a
Yea as sin 2(t) and sin (t) they are not in phase but I changed it to sin (t)(x+ycos(t)=a
Can't I take max amp =1 for sin t and cos t and find a? What's wrong with that method I don't fully understand
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Let $G$ be a finitely generated group, and let ${N_i}{i\in\N}$ be a descending chain of normal subgroups: [
G = N_0\supseteq N_1\supseteq N_2 \cdots
]
such that each quotient $\5{N_i}{N{i+1}}$ is finite.
\bigskip
How do I prove that if $G$ is residually finite, then $\bigcap_{i=0}^\infty N_i$ is trivial?
Aero
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no one will answer you
go on an alt account, post a chatgpt response
then someone will mad and correct it for u

Maybe post in https://discord.com/channels/268882317391429632/496784958430380033 . They might be more helpful. As for now, just wait until the next bot cycle comes. If nobody has answered by then, just close the post here and post in the channel provided.
sounds good
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hello, help me please
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why do they take tan(22/3) instead of tan(22/-3)? since the 3 is in the second quarant. im getting confused on like how i need to adjust these angles all the time. do i need to like add 180 or something after taking tan(22/-3)?
also why did they do tan(3/22) isnt it oppsoite over adjacen
did you draw a pic for this problem?
<@&268886789983436800>
Idk what you mean
that’s very confusing, how do I memorize like all the adjustments I need to do to get the right answer?
consider which angle you want in your diagram
ultimately you want to measure the deviation from North, in this case the green angle
and the simplest way to do that would be to consider
You do the red angle - 180
consider that triangle
which gives you the angle you want directly
ignore the negative sign in the -3 when calculating that
how did you know to flip the triangle how would I know to do that
by having a clear idea of which angle you want in your end goal
and marking that in your diagram
My plan was the get the angle and then like subtract 90 or whatever to get this angle
yeah but why is that arctan 22/-3 gives the angle in quadrant 4? I wouldn’t know that and it would make me get the problem wrong
you can take the arctan of (22/3),
ignore the sign of -3 for your reference triangle
the range of arctan is (-90°, 90°)
info about quadrant is lost when putting values into the arctan function
you'd either get something in Q1 or Q4 or 0
arctan(22/-3) would give you the red,
adding 180° would get you the blue
and subtracting 90° from that would give you the green angle
where's 22.3 coming from
doing arctan(22/3) gives you the size of the green angle
,w arctan(22/3) in degrees
Oh yeah I was looking at tan my bad
Result:
7.77
So you’re saying whenever you need to do arctan….just make the input positive and then manipulate it to get to the actual quadrant you need it
bc if you make it positive then you know it will always be in quadrant 1
that's the way i'd recommend doing it
Thanks for your advice
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is this formulation of Thales' theorem correct? "If a straight line is drawn in a triangle parallel to one of its sides, then this straight line divides the other two sides into proportional segments."?
I think soo
There apears to be two "thale's theorem"s
In geometry, Thales's theorem states that if A, B, and C are distinct points on a circle where the line AC is a diameter, the angle ∠ ABC is a right angle. Thales's theorem is a special case of the inscribed angle theorem and is mentioned and proved as part of the 31st proposition in the third book of Euclid's Elements. It is generally attribute...
The intercept theorem, also known as Thales's theorem, basic proportionality theorem or side splitter theorem, is an important theorem in elementary geometry about the ratios of various line segments that are created if two rays with a common starting point are intercepted by a pair of parallels. It is equivalent to the theorem about ratios in s...
@quartz scroll Has your question been resolved?
Ah.
- "Thales' Theorem": "If a triangle is inscribed in a circle with one side equal to the diameter, then this opposite angle is 90 degrees"
- "Thale's Intercept Theorem": "IF two parallel lines cut two rays, then they divide them into equal ratios".
So yes, you have the right wording, but for Thale's Intercept Theorem.
(also known as the Basic Proportionality Theorem)
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Part A should be (0.35 * 0.01) + (0.65 * 0.03) according to the Law of Total Probability
Part B can be expressed as P(A | D) but I don't know what method to apply here to solve the conditional probability
bayes rule
I know Bayes is often expressed as
$P(A|B) = \frac{P(B|A)P(A)}{P(B)}$
I think
I'd have to double check that one
The conditional probability formula is
$P(A|B) = \frac{P(A \land B)}{P(B)}$
Eyesonjune
What is it about this that makes it use Bayes and not conditional probability
Eyesonjune
What do you mean by conditional probability?
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Hello
Soo I have a problem in surface area and vol. Chapter
It's question no. 48
Anybody know how to get the height??
Height?
Ye i guess how to do this
Tell from beninging
The formula for hollow cylinder is π(R²-r²) h
Soo I guessed we need to find height...
If I'm reading the problem correctly, you aren't dealing with a cylinder.
@slender mirage ||Am I being dumb? With the measurements given I'm assuming the pipe makes a torus, no?||
Nah bro it isn't a torus
Then you, indeed, don't have the length of the pipe.
Bruh
And we're, at this point, imagining a tube which is 35cm thick
Not the tube itself, the material
Yeah okay
Seems silly, but if we concede that, it might just be asking for area per unit of length
Bro i don't think so
The idea of a truck having a pipe in the shape of a torus being similarly ridiculous, so it's not like I can put my interpretation on a high ground
Bro let me send u a diagram of the fig
It's a rough diagram don't gudge
Bruh leave it I'll come back to it later
Thanks for spending your time on my dumbass @warm grotto
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.@crimson vale Yes it is a Torus. With radius of cross-section given as 28cm. My response was to "a tube is a cylinder"
Oo shit, thanks dude
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what is the method to derive the right from the left
Personally, I’d cross multiply the right of the equation. If you aren’t given the right hand side, or have to manipulate the left hand side, I’d do long division
this is what I get with long division, what am i doing wrong
Somethings definitely wrong with your long division. I don’t know synthetic division, so I’m not sure where you went wrong, but you shouldn’t have an x greater than the first power.
can you show me what you know, the method you use for division?
Hold up for a second, I need to grab some pen and paper
okk thank you!!
Sorry if it’s a bit messy, I always skipped my handwriting class
Essentially, through long division. You can confirm that (x-2)(x^3+2x^2+x)+(3x^2+2x+1) = (x^4+1)
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Hi! So I need help in understanding using the quotient rule when it comes to negative exponents. There would be times I’d understand it and times when I don’t. For example (6x^3)^3/x^15.
I’m not sure how to solve it.
you're asking what if it was (6x^-3)^3?
Yes
