#help-28
1 messages · Page 286 of 1
i wont 
what are the xs in the middle column?
i see i see 
orz u 
because its "or"
well the people ordered by telephone, right?
🙂↕️ 
hello
you also orz
I have to study 4 more topics
you got this!
I also have to do hypothesis tests, bernoulli,
you'll breeze through them, i'm sure :)
oop cant help you with those, my math isnt good enough 
alr well best of luck!
!done
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i love clopen perms 
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hello so in the b)
the event C
It says the customer either orders online or orders tickets for a sporting event
ive notated it like this but i checked and "So" shouldnt be ticked, why?
ojhh
because "Orders online U Tickets for a sporting event“
"So" is included in both
therefore it only appears once
no
i dont understabd
What does Xo and X+ mean? Is it online and offline?
Oh it's Xo and Xt
Wdym Xo and Xt
its online and telephone
Yea I just got that
The X mark if theyre in the evnt
Yea
so why shouldnt be „So“ be marked
Because it's either-or
Huh
so he orders online or orders a ticket for sporting
Yep, but not both
Well this is a translation
its accurate
Yea which is why it matters
In language a lot of the time, Either or is used as an exclusive or rather than just an or
Think about this
If you read the instructions manual, either add boiling water or vegetable stock
What does that read like?
one of both but not both
Bingo
In language either or is used when you want exclusive or
Why cant we mark "So" and not mark "St"
Because you either book online or you book sports event via telephone
The second part of the condition is directly St
S = So U St
Because its "Online U Sports event"
Nope
Huh
I believe it would be
Online ∆ Sports
There is a reason why algebra pushed the field of math forward so far, and it was because it lowered ambiguities like these so much
man i fucking hate this subject
i hate every inch of this subject
not one thing did i like
hypothesis, bernoulli, nothing
We all have felt that way at least once in our life lol
Either or is being used here as symmetric difference or exclusive or
yeah i jsut didnt understand why ''So'' isnt being used
.
Either online or sports
O ∆ S
but sports can be online too?!
Yea but if it were online it would be both
Language my dear friend is complicated asf.
Wait so
Either online, or a sports event
But if its an online sports event that would mean that its not either anymore
holy hit
i think i understood it
because
If its ''So, Ko, Mo, Eo''
If youd have So then
its would be contradictory to C
Because the customer either orders online or a ticket for a sporting event
Ik you repeated the statement but hopefully you understood it lol
if you would have ''So'', youd have both online and sporting event
done
i understood it
Okay we move on
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Ok lmao
,rotate
Okay so
D = A not U C not
that means that we basically do
A and C
just flip everything right
There's a bar over that as well
Also you can use latex
@glacial stream
${\bar A\cap\Bar C}$
law
There would be double bar
$\bar{\bar A} \cap \bar{\bar C}$
@glacial stream
never seen that before
Oh not even $\bar{\bar A} = A$?
@glacial stream
No you used $\bar A$
@glacial stream
not not A = A ≠ not A
It would not be A or C I tell you that much
i have to relearn these rules
uhhh
so i can do
0.55 = -4 * (3b) ...
and so on
right
thats 1 equation?
but how do i get the other 2
no we need 4
we have 4 unknowns?
@glacial stream r u there bro
<@&286206848099549185>
hello anyone
If P(-2≤x≤2)=0.35, what can you deduce
uhh
that from -1 to 2
its 0.35
or wdym
Yup
Then you need one more equation
Here's a hint, think of what the sum of all probabilities have to equate to
1
wtf
yes cuz
but
wait
what about the 4th equation
oh
im delusionla
sorry
yes tysm guys
i wish i was smart
il continue tomorrow
Just practise more and more and you'll get there eventually
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Have you drawn a sketch?
@summer creek Has your question been resolved?
Forget my abysmal drawing skills but this should be the figure.
why is it so dark in the picture.
😭
I found a scale so uh
Here.
,rccw
should I send a brighter screenshot or is it fine? 😭
It's good
kk.
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✅ Original question: #help-28 message
also what is a circumradius.
I think thats the circle that goes through the 3 points
circumcircle.
Radius of it*
radius of circumcircle. Fire. Lemme now try to find a way.
first thing I'm thinking of is like. To extend the perpendicular bisectors inwards because if we take PQ and PS as chords of the circle. Then the perpendicular bisectors meet at the center.
Sorry I g2g (tbh I'm not good at geometry anyway, just tips and stuff, you can ping Helpers role if anyone else is online)
try not to ping for OP though
cuz it's pointless to ping for OP when OP is MIA and now you have a horde of helpers waiting on OP
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!status
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2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
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7. None of the above
2
,, \begin{align}
x^9 -x &= x(x^8 -1)
\&= x\left((x^4)^2 -(1^4)^2\right)
\&=x\left((x^4+1)(x^4-1)\right)
\&=x\left((x^4+1)((x^2)^2 -(1^2)^2\right)
\end{align}
bruh
\\ for newlines
calvin
why are you wrapping (x^4-1)(x^4+1) in an extra set of brackets
idk
are you an associativity hater
whats that
keep going tho
associative law is the law that says (a×b)×c = a×(b×c)
,,x(x^4 +1)(x^2 -1)(x^2 +1)
calvin
calvin
Yes
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✅ Original question: #help-28 message
Find two four digit numbers such whos product is $4^8 + 6^8 + 9^8$
calvin
,w calc 4^8 + 6^8 + 9^8
Hm, notice you can write $4$ as $2 \cdot 2$, $6$ as $2 \cdot 3$ and $9$ as $3 \cdot 3$
1 divided by 0 equals Infinity
calvin
Yep
Use some exponent rules
Aka if i let $a = 2^8$ and $b = 3^8$, what would the expression turn out to be
1 divided by 0 equals Infinity
,,3a+ 3b
calvin
How'd you get that
calvin
right?
I don't get how you got $3 \cdot 2^8 + 3 \cdot 3^8$
1 divided by 0 equals Infinity
(2×3)^8 ≠ 2×3^8 btw
oh im mistaken
,,2^8 \cdot 2^8 + 2^8 \cdot 3^8 + 3^8 \cdot 3^8
calvin
,,a^2 + ab + b^2
calvin
Yep
so now
That should be your first instinct
idk
Now you want to factorize this
But this can't be neatly factorize
,,(a+b)^2 -ab
calvin
How are you supposed to factorize this
That's a problem
Another approach is that you can let $a = 2^4$ and $b = 3^4$
1 divided by 0 equals Infinity
,,(a+b-\sqrt{ab})(a+b+\sqrt{ab})
ch3rry
Root shouldn't be a prob its even powers
Hey does someone know how to do?
!occupied
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I just realized that after i introduced a new variable declarations
,,
2^8 \cdot 2^8 + 2^8 \cdot 3^8 + 3^8 \cdot 3^8 = \left(2^4\right)^2 \cdot \left(2^4\right)^2 + \left(2^4\right)^2 \cdot \left(3^4\right)^2 + \left(3^4\right)^2 \cdot \left(3^4\right)^2
\= a^2 \cdot a^2 + a^2\cdot b^2 + b^2 \cdot b^2 \= a^4 + a^2b^2 + b^4
bruh
1 divided by 0 equals Infinity
Then continue
idk
,,x^a\cdot x^b=x^{a+b}
ch3rry
did i fuck up my exponents
...
what the hell am i doing sorryyy
Nope there's no 2 here
omh
Neither should it be here
calvin
im selling
Why's arent u doing this
can you teach me how to factorise like that
,,(2^8 + 3^8 -2^4 \cdot 3^4)(2^8 + 3^8 +2^4 \cdot 3^4)
calvin
,, x^2-y^2=(x+y)(x-y)
ch3rry
Yep
...now u gotta calc it i think :>
,w 2⁸+3⁸-6⁴
,w 2⁸+3⁸+6⁴
,w 8113×5521
||i accidentally introduced just to make factorizing neater||
how do you get this
Uhh try identifying what x and y are here
wdym
oh its
ohhh
i basically helped with the answer
im so smart
😂😂😂
Glad you said that 
😭😭😭
-# 
all good thanks for the help guys
Tbh i couldn't see that factorization bc it ain't neat
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I would want to work with neat expressions
ye
Because this has square roots which i didn't even think of
yh true
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$(1+i)^{2z}=n$
Goofy Joe
Find z
!status
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2. I have begun but got stuck midway.
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7. None of the above
$\ln((1+i)^{2z})=\ln(n)$
Goofy Joe
$z=\frac{\ln(n)}{2\ln(1+i)}$
Goofy Joe
$\ln(1+i)=\ln(\sqrt{2})+i({\frac{\pi}{4}+2k\pi)$
Goofy Joe
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reaction for more information.
(You may edit your message to recompile.)
$z=\frac{\ln(n)}{\ln(2)+i({\frac{\pi}{2}+4k\pi)}}$
Goofy Joe
Right ?
4
right
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correct as principal solution but not as general solution
not sure which one you're looking for
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✅ Original question: #help-28 message
why not general
<@&286206848099549185>
Hi
Can you check my work pls
Of what
log is multivalued for complex numbers so for a general solution, you would need an extra +2piik term
in that step
Where
I just need to calculate the logarithm of n
$z=\frac{\ln|n|+i2k\pi}{\ln(2)+i({\frac{\pi}{2}+4k\pi)}}$
Goofy Joe
So this
What is the original question?
$(1+i)^{2z}=n$
Goofy Joe
Just find z or is there any other info given?
Solve the equation
If I were you I'd rewrite the left side like this first $(1+i)^{2z} = e^{2z\ln(1+i)}$
bartdestinkerd34
Then take the multivalued ln
$e^w = n \Rightarrow w = \ln n + 2\pi i k,\quad k\in\mathbb{Z}$
bartdestinkerd34
@sturdy vine Has your question been resolved?
also, ln n is meant to be ln|n|
Thanks all
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Hello, could someone check if this proof looks good please?
\begin{Definition}[Divisibility]
A nonzero integer $a$ is said to \emph{divide} an integer $b$, written $a \mid b$, if $b = ak$ for some integer $k$.
\end{Definition}
% --------------------------------------------------------------------------------
\begin{Theorem}
Assume $a, b$ and $c$ are integers. If $abc$ is a multiple of 10, then at least one of $ab$, $ac$, or $bc$ is a multiple of 10.
\end{Theorem}
\begin{proof}
Let $a, b$ and $c$ be integers, and $abc$ a multiple of 10.
So, by the definition of divisibility, $abc = 10k = 2(5)(k)$ for some integer $k$.
This is means that $2 \mid abc$ and $5 \mid abc$.
Without loss of generality, assume that $2 \mid a$ and $5 \mid b$, which means that $a = 2l$ and $b = 5m$ for some integers $l$ and $m$.
Then, $abc = 2l(5m)(k) = 10lmk$.
In this case, $ab$ is a multiple of 10.
A similar case can be constructed for $5 \mid a$ and $2 \mid 5$, and with either $a$ and $c$, or $b$ and $c$.
Then, at least one of the three is divisible by 2 and one of the two left are divisible by 5.
Therefore, at least one of $ab$, $ac$, or $bc$ is a multiple of 10.
\end{proof}
Mor Bras
you can't assume 2 | a and 5 | b, for example if i pick a = 10 and b = c = 1
looks alright but i think defining a := 2l and b := 5m seems redundant. you can just conclude that if 2 | ab and 5 | ab then 10 | ab. also 2 | 5 looks like a typo?
and yeah you're neglecting the possibility that 10 | a and not any other of b or c
Certainly, I'm fixing the proof accordingly to your comments
@ember quartz Has your question been resolved?
Here's the fixed version:
\begin{Definition}[Divisibility]
A nonzero integer $a$ is said to \emph{divide} an integer $b$, written $a \mid b$, if $b = ak$ for some integer $k$.
\end{Definition}
\begin{Theorem}
Assume $a, b$ and $c$ are integers. If $abc$ is a multiple of 10, then at least one of $ab$, $ac$, or $bc$ is a multiple of 10.
\end{Theorem}
\begin{proof}
Let $a, b$ and $c$ be integers, and $abc$ a multiple of 10.
So, by the definition of divisibility, $abc = 10k = 2(5)(k)$ for some integer $k$.
This is means that $2 \mid abc$ and $5 \mid abc$.
Without loss of generality, assume that $2 \mid a$, which means that $a = 2l$ for some integer $l$.
Then, $abc = 2lbc$.
Now, either $ 5 \mid l$ or $5 \cancel\mid l$.
If $5 \mid l$, then $ 10 \mid a$, so $10 \mid ab$ or $10 \mid ac$.
If $5 \ \cancel\mid \ l$, then, either $5 \mid b$ so $10 \mid ab$, or $5 \mid c$ so $10 \mid ac$.
In any case, $ab$ or $ac$ is a multiple of 10.
A similar case can be constructed for with either of the rest of the variables $b$ and $c$.
Then, at least one of the three is divisible by 2 and one of the two left are divisible by 5.
Therefore, at least one of $ab$, $ac$, or $bc$ is a multiple of 10.
\end{proof}
Mor Bras
you already said WLOG so you don't really need that last paragraph. i'd phrase it like 2 | abc, so we know either 2|a, 2|b, or 2|c. WLOG, assume 2|a, which means...
have some bad sols because they were too funny not to post here
Yes, I was thinking about the pingeonhole principle too
But with the boxes as 2 and 5, and the pigeons as a, b, and c, but that doesn't work
boxes are ab, ac, bc, pigeons are 2 and 5
yeah saying WLOG is the same thing as saying the rest follow from a similar case
in this case it's probably obvious enough that you don't need to explain why beyond clumsy's suggestion
\begin{Definition}[Divisibility]
A nonzero integer $a$ is said to \emph{divide} an integer $b$, written $a \mid b$, if $b = ak$ for some integer $k$.
\end{Definition}
% --------------------------------------------------------------------------------
\begin{Theorem}
Assume $a, b$ and $c$ are integers. If $abc$ is a multiple of 10, then at least one of $ab$, $ac$, or $bc$ is a multiple of 10.
\end{Theorem}
\begin{proof}
Let $a, b$ and $c$ be integers, and $abc$ a multiple of 10.
So, by the definition of divisibility, $abc = 10k = 2(5)(k)$ for some integer $k$.
This is means that $2 \mid abc$ and $5 \mid abc$.
So we know that either $2 \mid a$, $2 \mid b$ or $2 \mid c$.
Without loss of generality, assume that $2 \mid a$, which means that $a = 2l$ for some integer $l$.
Then, $abc = 2lbc$.
Now, either $ 5 \mid l$ or $5 \ \cancel\mid \ l$.
If $5 \mid l$, then $ 10 \mid a$, so $10 \mid ab$ or $10 \mid ac$.
If $5 \ \cancel\mid \ l$, then, either $5 \mid b$ so $10 \mid ab$, or $5 \mid c$ so $10 \mid ac$.
In any case, $ab$ or $ac$ is a multiple of 10.
The rest follow from a similar case.
% Then, at least one of the three variables is divisible by 2 and one of the two left are divisible by 5.
Therefore, at least one of $ab$, $ac$, or $bc$ is a multiple of 10.
\end{proof}
Mor Bras
Looks good. The biggest "leap" here is saying that if 5 does not divide l, then it must divide b or c. If you're comfortable with why that is, then I'd say you're done
I would get rid of "The rest follow from a similar case". That's already covered when you assume 2|a WLOG.
10 must divide abc by assumption, and 2 divides a. If 5 doesn't divide a, then it must be that either 5 divides b or c, so to have 10 divides ab or ac, and so 10 divides abc. I may need to think in more about the detail of "if 5 does not divide l, then it must divide b or c"
If you want a similar, slightly simpler step to check justification, why does 2|abc imply 2|a, 2|b, or 2|c ?
Because, in the case of 2 | abc implies 2 | a or 2 | bc, either
- 2 | a, then is given,
- or 2 doesn't divide a, then since 2 is prime, the gcd(2, a) = 1, and by bézout's identity, 2 must divide bc.
Reaplying this for bc, then 2 divides either b or c. Therefore, 2|abc imply 2|a, 2|b, or 2|c
Now I see, I'll correct this with a couple of lemmas.
@ember quartz Has your question been resolved?
I don't mean to make you do everything in excruciating detail
The justification for this is fairly similar, so I was checking if you knew it
It allows me to be more verbose, which is something I want to do, but I didn't know I could be more detailed in this, so thanks for pointing it out 👌
Ah all right, nice
I'll close this for now, as I'm having troubles with latex
Thanks for your responses!
.close
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✅ Original question: #help-28 message
Ok, so here's the fix:
\begin{Definition}[Divisibility]
A nonzero integer $a$ is said to \emph{divide} an integer $b$, written $a \mid b$, if $b = ak$ for some integer $k$.
\end{Definition}
\begin{Lemma}
Let $a$, $b$, and $c$ be integers, and let $p$ be a prime.
\begin{enumerate}
\item\label{l1} If $p \ \cancel\mid \ a$, then $\gcd(p,a) = 1$.
\item\label{l2} If $a \mid bc$ and $\gcd(a, b) = 1$, then $a \mid c$.
\item\label{l3} If $p \mid bc$, then either $p \mid b$ or $p \mid c$.
\end{enumerate}
\end{Lemma}
% --------------------------------------------------------------------------------
\begin{Theorem}
Assume $a, b$ and $c$ are integers. If $abc$ is a multiple of 10, then at least one of $ab$, $ac$, or $bc$ is a multiple of 10.
\end{Theorem}
\begin{proof}
Let $a, b$ and $c$ be integers, and $abc$ a multiple of 10.
So, by the definition of divisibility, $abc = 10k = 2(5)(k)$ for some integer $k$.
This is means that $2 \mid abc$ and $5 \mid abc$.
So we know that, because 2 is prime, by lemma 2.3, either $2 \mid a$, $2 \mid b$ or $2 \mid c$.
Without loss of generality, assume that $2 \mid a$, which means that $a = 2l$ for some integer $l$.
Then, $abc = 2lbc$.
Now, either $ 5 \mid l$ or $5 \ \cancel\mid \ l$.
If $5 \mid l$, then $ 10 \mid a$, so $10 \mid ab$ or $10 \mid ac$.
If $5 \ \cancel\mid \ l$, then it must be that $5 \mid bc$, and, since 5 is prime, by lemma 2.3, either $5 \mid b$ so $10 \mid ab$, or $5 \mid c$ so $10 \mid ac$.
In any case, $ab$ or $ac$ is a multiple of 10.
The rest follow from a similar case.
Therefore, at least one of $ab$, $ac$, or $bc$ is a multiple of 10.
\end{proof}
Mor Bras
im impressed with the proof you got there
did you learn congruency yet?
No, I'm learning how to write proofs, right now I'm with direct proofs, and divisibility is one of the topics the book covers for this kind of proofs
Certainly
definition: $a \equiv b \mod{m}$ for $a, b, m \in \mathbb Z$ when $m \mid a - b$
1 divided by 0 equals Infinity
by words, $a$ and $b$ has the same remainder when dividing by $m$
1 divided by 0 equals Infinity
Ah yes, the book touches this is some exercises
cool
try to prove some basic properties of it first
for example:
if $\begin{cases} a \equiv b \mod{m} \ c \equiv d \mod{m} \end{cases}$ then $a + c \equiv b + d \mod{m}$
1 divided by 0 equals Infinity
or
if $\begin{cases} a \equiv b \mod{m} \ c \equiv d \mod{m} \end{cases}$ then $a - c \equiv b - d \mod{m}$
1 divided by 0 equals Infinity
Of course
or
if $\begin{cases} a \equiv b \mod{m} \ c \equiv d \mod{m} \end{cases}$ then $ac \equiv bd \mod{m}$
1 divided by 0 equals Infinity
these only need some algebraic manipulations
For sure
<@&286206848099549185> Hello, could someone else check if this proof looks good?
hello
Hi
send in the proof
Yes
\begin{Definition}[Divisibility]
A nonzero integer $a$ is said to \emph{divide} an integer $b$, written $a \mid b$, if $b = ak$ for some integer $k$.
\end{Definition}
\begin{Lemma}
Let $a$, $b$, and $c$ be integers, and let $p$ be a prime.
\begin{enumerate}
\item\label{l1} If $p \ \cancel\mid \ a$, then $\gcd(p,a) = 1$.
\item\label{l2} If $a \mid bc$ and $\gcd(a, b) = 1$, then $a \mid c$.
\item\label{l3} If $p \mid bc$, then either $p \mid b$ or $p \mid c$.
\end{enumerate}
\end{Lemma}
% --------------------------------------------------------------------------------
\begin{Theorem}
Assume $a, b$ and $c$ are integers. If $abc$ is a multiple of 10, then at least one of $ab$, $ac$, or $bc$ is a multiple of 10.
\end{Theorem}
\begin{proof}
Let $a, b$ and $c$ be integers, and $abc$ a multiple of 10.
So, by the definition of divisibility, $abc = 10k = 2(5)(k)$ for some integer $k$.
This means that $2 \mid abc$ and $5 \mid abc$.
So we know that, because 2 is prime, by lemma 2.3, either $2 \mid a$, $2 \mid b$ or $2 \mid c$.
Without loss of generality, assume that $2 \mid a$, which means that $a = 2l$ for some integer $l$.
Then, $abc = 2lbc$.
Now, either $ 5 \mid l$ or $5 \ \cancel\mid \ l$.
If $5 \mid l$, then $ 10 \mid a$, so $10 \mid ab$ or $10 \mid ac$.
If $5 \ \cancel\mid \ l$, then it must be that $5 \mid bc$, and, since 5 is prime, by lemma 2.3, either $5 \mid b$ so $10 \mid ab$, or $5 \mid c$ so $10 \mid ac$.
In any case, $ab$ or $ac$ is a multiple of 10.
The rest follow from a similar case.
Therefore, at least one of $ab$, $ac$, or $bc$ is a multiple of 10.
\end{proof}
Yes, the whole thread is for this proof

Mor Bras
i think the proof is okay
do you need to prove the lemmas btw 
great proof taught me some latex 👍👍
$\LaTeX$
1 divided by 0 equals Infinity
thank you for teaching me more latex
It's true, but then the proof would be quite lengthy, and because I think the topic is "basic", I just proof the theorem, and the rest are definitions and lemmas
now all that I need to know is if it is lah-tek or lay-tek
what's $\pi \left( \frac{1}{2} - \frac{1}{4} - \frac{1}{8} - \frac{1}{16} - \frac{1}{32} - \frac{1}{32} \right)$ btw?
1 divided by 0 equals Infinity
lah-tek
@turbid badge
okay we've sidetracked too much mb I'll take my leave
specifically 0 and some latex
night
anyways
whenever you finished perfecting your proof
you can
!done
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hello,
@proven lynx Has your question been resolved?
Not sure what's going on here. The only possible values of $X$ in the interval $[-2,2]$ are $-1$, $0$, and $2$. So,
\begin{align*}
P(-2 \leq X \leq 2) &= P(X=-1)+P(X=0)+P(X=2) \
&= (b+c)+(d-c)+0.05
\end{align*}
gtg, but hope this helps!
Civil Service Pigeon
yes i understand i was confused
i thought i have to multiply the -1 and 0 and 2
with the corresponding P(x)
That's when you find expected value
but this is a probability
oh yeah okay
@proven lynx Has your question been resolved?
LUC1DV1B3S_010
$\LaTeX$
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Hi, I'm trying to do this problem in this geometry video in Khan Academy before it's shown in the video how to do it and was wondering if someone could nudge me in some direction but without any hints.
This is my work so far
I'm thinking maybe I can construct a line between point E and C to make a statement that triangle ECG is congruent to triangle EBG because of side angle side triangle congruency and that might possibly help me with figuring out the measure of angle BED?
Then the sum of angle BEG and GEC and CED equals the measure of angle BED.
Quick question, im allowed to refer to the unit circle?
I haven't learned it yet, it's in Algebra 2 in the trigonometry unit in Khan Academy.
I'm learning high school geometry on Khan Academy.
Okay i know the angle that forms but i have 0 clue about how the proof for it being that angle is carried
lemme try to think a bit ig.
by that angle you mean angle BED right?
Take your time!! 🩷 ty for helping me <33
once you find any of the useful angles the problem basically falls off as trivial tbh
Hmmm
I also know that if we continue line DE then the sum of angles (let's call the new point that forms point Z) then the sum of angle ZEB, BEG, GEC, and CED have to equal 180 degrees, does that help me?
Can you continue lines? is that a thing?
Yeah you can continue lines
Nice
You can anything basically, but im not entirely sure that helps
Since we dont know / cant prove where Z is
Right
First of all, lets assume that AB is = 1
But I think maybe if we do algebra then that'd help immensely, like if we know 3 of the angles for example then the 4th has to be known with algebra.
it just makes everything easier
Alright
that's fair
Unit square? is that an appropriate term?
Nice
I also know that BE is the radius of the circle, because the center of it is at b and one line segment connects it to the circle so that has to be a radius right?
BG = 1/2
How do we know that BG = 1/2?
i dont see it
Ohhhhhhhhhhhhhhhhhhhhhhhhhhh
Nevermind I don't see it
Can you show me?
Nope
This makes sense to me intuitively though
okay, theres another way to show it anyways.
The distance between BG and BC is 1/2 the total line right?
Notice, the triangle BEG is just a reflection of triangle CEG
Right!
Since they are reflections
Yeah
What is the length CE?
It's 1
join the two triangles
Because it's congruent to BE
Mb took a sec
NP
I mean, we are looking at two triangles with a shared side
BEG and CEG
Ignore G and join them into a bigger triangle
CEB
Also I realized now that the radius BE is the same as the length BA and BC right? Or does that need to be proved?
It does not need to be proved, no
Check the sides of the triangle now
Now their measure has to be 90 degrees, which means that the measure of BED - 90 degrees = the unknown angle, and added together we get BED
What are the lengths BE, BC and EC?
Ah now it's an isosceles triangle right?
BC = 2?*
What are the internal angles of any equilateral
60?
Why isn't angle BEC = 90?
The mirror of triangle DFE from the bottom left corner?
I suppose the reason that earlier we can pick radius 1 for segment BE is because whatever the true number is the proportions stay the same?
So if instead of 1 the radius was actually 4 then the logic still stays the same?
That's really sick
Try to construct the Triangle BEC and check if its looks like a 90º angle
Also I really appreciate the ancient greeks figuring out SAS and other triangle congruencies because it makes it way easier to prove congruency of certain triangles.
I've got the answer
Sharing in some time
To be honest, theres a point of no return in trigonometry where you learn that trig is in reality based on circles
And past that you become a lazy fuck like me
Logically it has to though? Because 90+2x=180 and so x has to equal 45 and BEG+GEC = 90?
I'm not looking for it, and that's not what this server is for. Please don't share it without guiding me properly.
Dont' share the answer please
I'm solving it
On my own
Nice
How? every triangle has to add to 180 degrees.
Right angles always have a 90º angle
Yep
theres nothing specified on any of the other two
This is insane, I didn't know that!
Well, we have this now
How do I find this out though?
Again, we stated that every equilateral has 60º angles
and you were the one that found that all sides had length 1
Because EC and BE are equal and are 1
Yep
This helps a lot because all that's left is this triangle now and we have to find the angle.
Yep
60+ that angle = BED
This triangle as an important fact
That makes sense
Yep
you also want CD too.
Also, we have a transversal right?
The transversal doesnt really matter
Oh ok
The middle one has length 1, and the bottom one has to also be one because it's congruent to BA because it's a square.
Am i right?
i mean does that prove it?
Yep, so its an isosceles
You also technically know the bottom-right angle of that triangle.
We can use area of sector also
I don't know that
If we see the figure ACB is a quadrant
I don't see how
Ar of sector AEB + Ar of sector BEC= ar of quadrant ACB
You know that the corner is a 90º, as of all squares
and you know the inner angle of the equilateral thats just above our triangle of interest.
i don't know what you're talking about, i'm gonna listen to @sonic stratus for now if that's ok
In which grade are you?
I won't share that
this is completely unnecesary tbh, you can do this only by appealing to a really basic trig identity.
That's right!
So 90-60=30
Now, isosceles have the nice property of sharing 2 equal angles apart from 2 equal sides.
And since we know that it's an equilateral the two opposite sides have to each be 75
Right?
not equilateral, but yeah, the idea is right
Sorry I mean isosceles
yeah, and you now already have BED
Make sure to draw over your problem to calculate the whole thing
60+75=135=BED!
yea
Ill just spoil you like 2 years of study
Yeah?
the thing i mentioned at the start where i already knew the important angle
That's just a trig identity?
not really
is because its a result that theyll engrave into your brain, lmao
Oohhh XD
that's cool!!!
I really appreciate it!!!
@forest hawk Thank you too!!!
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$$x = \frac{2y^2+6}{3y-3}$$
hoax
Let's see how you cooked this
$$ x(3y-3) = 2y^2 + 6$$
$$\frac{d}{dy}(x(3y-3)) = \frac{d}{dy}(2y^2 + 6).... \text{differentiating both sides with respect to y}$$
hoax
overcomp
are you not able to just do quotient rule?
or better yet, do some long division and then differentiate
nah imma just do product rule instead
Same thing
Well uhm, this is complicated already
$$\frac{dx}{dy}(3y-3) + 3x = 4y+6$$
it's not
hoax
It's just complication
you will get something implicit when there is no good reason for it
and then from here i can just isolate the dx/dy
Quotient rule and product rule are a mess to deal with if differentiated directly from this
I'd rather do long division
also there shouldn't be plus 6
i got the expression x(3y-3) on the LHS, and 2y^2 + 6 on the RHS
differentiating both sides with respect to y
we apply product rule on the LHS
What's the purpose of this anyway
i am doing questions rn
for
math exam soon
You're just overcomplicating yourself rn
it's from this if ur wondering anyway
-# why u hate quotient rule
I meant what's the purpose of cross multiplying here
-# or long division
Then long division
i get (4y-3x)(3y-3)
Long division not rlly complicated
dx/dy
-# its p quick in this case
-# quotient rule yay
like what am i doing wrong/
-# i agree that quotient rule is ugly and i can't sven remember ts, but i'd rather do long division here
also why is ur text so tiny
What even IS the purpose of cross multiplying in your case
if u look up and check my working
much easier to deal with
unless im doing something wrong
How are you going to get $x'$ alone on 1 side
1 divided by 0 equals Infinity
and i also asked "what am i doing wrong here??"
That's the problem
6 constant
@hot kernel try to answer this
i thought it'd just be derivative of x with respect to x multiplied by derivative of y with respect tox
unless im thinking about the chain rule incorrectly
Can you fact-check this? (Not the replied msg, the msg that was recently sent)
Which msg what
This one
Why not just use quotient rule
Ugly (that's the whole reason)
Not my opinion tho
Im not even crazy enough to cross multiply all of this
i have the expression x(3y-3)
dude it's not hard to cross multiply x(3y-3) what?
so i have the expresssion x(3y-3)
if i decide to differentiate this expression with respect to y
applying the product rule, won't we just get (dx/dy)(3y-3) + x(3)
How are you differentiating $x(3y - 3)$ with respect to $y$
1 divided by 0 equals Infinity
$x'(3y - 3) + 3x$ you mean?
1 divided by 0 equals Infinity
but you will get dx/dy in terms of x and y
and you have to put x=(original fraction) back in
you don't actually save any effort in this way
Which is more complicated
oh right
Also d( 2y²+6)/dy = 4y
i get something implcit i see
Diff of 6 is 0
If you think quotient rule is ugly, try long division
no u see i am just used to implicit differentiation that i did not see we get dx/dy explicitly
that's called tunnel vision
$\frac{2y^2 + 6}{3y - 3} = \frac{2(y - 1)^2 + 4(y - 1) + 12}{3(y - 1)}$
1 divided by 0 equals Infinity
This is much easier to differentiate (thank god i did my calculations correctly)
i will do you one better
-# poor quotient rule getting hate for no rsn
$$x = (2y^2+6)*(3y-3^{-1}$$ product rule this if you not comfortable with quotient tbh, this would be more ugly
heisenberg
$\frac{2y^2+6}{3y-3}=\frac23\cdot\frac{y^2+3}{y-1}= \frac23\paren{y+1+\frac{4}{y-1}}$
Ann
Or this
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1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
1
i dont understand the explanation of the solution
AP means the addition principle btw
S1
x^2+y^2<=5 means x^2+y^2 is precisely any of 0,1,2,3,4,5
@undone radish they are counting up how many pairs (x,y) satisfy x^2+y^2=0, then x^2+y^2=1, etc up to 5. then they add those counts up.
ohh okay
is the only way trial and error
no
you can make do with some symmetry arguments i guess
Does stars and bars work here?
but some case checking will be required
for numbers this small you might as well “trial and error”
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for large enough values of 5 it'll be more efficient to go row by row
7C2...
Like, try each x-value one by one and count number of y-values
probably just coincidence?
you could do it more dynamically/recursively for larger numbers than 5
Well we already see that for radius 2 the value is 13
that isn't nCr for any n≤13
Yeah
Oh yeah lol
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I would start by writing out the definitions
monic gf:
∀uv, g∘f∘u=g∘f∘v → u=v
tfw no monic gf
Ok, let's assume this is true and true to prove that f is monic
@lean rock Has your question been resolved?
Look I proved it with tableux! 
tree closes, so it's logical truth ∎
Sorry it's not entirely accurate with the variable because I left sketches, I can edit it, one sec
Assume gf is monic. Then, we need to show for all u,v that fu=fv => u=v
fu = fv (assumed premise)
gfu = gfv (left-compose by g)
u=v (gf is monic)
if you want a more readable proof
Thank you so much!
np!
the argument is
P
∴ Q
write premises with the conclusion negated in a tree:
P
¬Q
this means P∧¬Q
and show if premises are true the conclusion cannot be false,
this tree closes with the conclusion negated, so if the premises are true the conclusion cannot be false
but I maybe am making mistakes as I am learning this now
yours is more elegant 🌟
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how do I do this?
what I tried was, to map out the possibilities
(5, 2) (1/3, 1/4)
(2, 5) (1/6, 1/4)
(4, 3) (1/3, 1/4)
(3, 4) (1/6, ,1/4)
and then calc
3/12 / 1 = 1/4
its given that sum can also be more than 7, so you would need other cases like (5,3), (5,4), (5,5) etc
Try calculating probability that the sum is less than 7, then take its complement, it might be easier
do we need to consider that the sectors are not equal?
yeah
OH
OML
i thought exactly 7 omg
i keep messing up cus i don't read the question
yeah lemme try it out
okay well still seems wrong
(2, 2), (3, 3), (2, 3), (3, 2), (4, 2), (2, 4)
(1/6*1/4) x 4 + (1/3x1/4) x 2 = 1/3
where'd I go wrong this time?
right
(1/6*1/4) x 5 + (1/3x1/4) x 1
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rare instance where we assume perfect friction
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!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
1
What are you trying to do with this expression?
I’m tryna prove it u feel

