#help-49
1 messages · Page 210 of 1
for 1 @real marlin
yeah
bro i need work to show
if op finds it more convenient, why not
now add 49 to both sides
As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.
probably school's load
bro i have exam in 3 days i dont know any of this
please do not call me "bro".
oh
her*
check pronouns before talking
yeah i just use that word but ok
This algebra video tutorial explains how to solve simple quadratic equations using the square root feature. This video contains plenty of examples and practice problems.
Quadratic Equations - Free Formula Sheet: https://bit.ly/3WZ8v1Z
How To Solve Simple Quadratic Equations:
https://www.youtube.c...
here is a playlist that you should watch
and/or go to khan academy
@lyric charm do i help or hop onto another section
dunno
you can cram some of it in for sure! but i would doubt that you can get from "zero algebra skills" to "good at algebra 1" in 3 days
you will have to study now and after the exam imo
should probably look for another section -- but remember not to do ppls work for them still
yeah ill be back on this server in three days lets just say
thank you for the answers that was fast
||irony spotted||
what
you can only close your own channel
helpfuls and above have permission to close anybody's
hope you crash the exam..
🙂
.close probably
.close
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too late
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how do i do c
just solve the inequality and check the interval against the zeroes you find
Its a similar logic to A and B (assuming you did those)
have you been able to do a and b?
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This is my work for a and b
,rccw
mmm no good
im seeing a problem here
you cannot go from ab < 0 to any combination of a<0 and b<0
also unclear wtf your final answer to either one is
Im so fucking stupid
Think on what Ann said for a few minutes, maybe try redoing the problems, and if you don't feel confident in that endeavor, we're here
do not beat yourself up like this please
i will say that your factorization for a is correct
and likewise for b
Was I supposed to do something like this
this is good but a bit overkill
The solution for the zeroes of problem A appears to be right, explanation works for me.
It’s just how I was taught it
I just learned this today
do you still have a question about problem C and do you think you can solve problem B? because those problems don't add any difficulty compared to this problem A
I just cant figure out the factoring for c
idk why I thought -6+2=-2 yeah you'll have to complete the square
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Hi
hello shinji
"the normal formula" could mean a million things
24??? 💔
*21
shi
did you miss a word there?
did you mean "sum of the first 126 multiples of 7"?
i am so braindead after acid-base equilibrium 🥀
this right?
and what does "normal formula" mean to you?
well you are summing an AP, yes
So do i just gotta do the formula?
if you can't function without an obligation then yes
I didn't understand what you meant
otherwise there is an alternative: you could realize your sum is equal to 7(1+2+3+...+126) and then recall how to find the sum of the first n natural numbers
if you feel like you need someone telling you you "have to" do something then i will say so
Uh
I was just not sure tbh
The question was different from the 1st anyways
So yea
Lemme finish it first
what 🥀
you CAN apply the formula for the sum of an AP
and you have all the data for it correct
im just saying there shouldn't be a "have to" attached to it
Sorry
Uh
Last question
hi
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oh yeah that's that one riddle
fff trick gets us that f(3n)=f(f(f(n)))=3f(n)
,w factorize 1992
gimme a sec
f:z->z and f strictly increasing implies f(x)>=x
n=1 gets f(f(1))=3
if f(1)=1, then that implies f(f(1))=f(1)=3 which is impossible so f(x)=/=x, that implies f(x)>x
if f(1)>=3 then f(f(1))>=f(3)=3, but we determined that f(x)>x, so impossible
this f(1)=2
f(f(1))=f(2)=3 so f(2)=3
f(f(2))=f(3)=6
so f(3)=6
Ohhh I think I have seen this somewhere on the internet
f(f(3))=f(6)=9 so f(6)=9
since 6=f(3)<f(4)<f(5)<f(6)=9 then that implies f(4)=7 and f(5)=8
you can repeat this for every multiple of 3, but im not sure how to write it exactly
when in doubt, induction
yeah something like that, but like that is going to take forever to reach 1992
yeah that was i wanted to use but im not sure how to really do it, lemme write it first
claim that f(n)=n+9 forall n>=9
by strong induction, assume it holds for all n up to k, base case is true, then
f(k)=k+9 <=> f(3k)=3k+27
f(k+1)=k+10 <=> f(3k+3)=3k+30
since 3k+27=f(3k)<f(3k+1)<f(3k+2)<f(3k+3)=3k+30, which implies f(3k+1)=3k+28 and f(3k+2)=3k+29
but how do you make sure it covers all x>=3
ehh wait actually why is f(3k)=3k+9
is it really the case
your claim is false
yeah i noticed that
1 -> 2 -> 3 -> 6 -> 9 -> 18 -> ...
whats the correct clain then
oh yikes
so i dont think this will work then
f(1)=2
f(2)=3
f(3)=6
f(6)=9
f(9)=18
f(12)=21
f(15)=24
f(18)=27
f(21)=36
f(24)=45
f(27)=54
ohh the pattern is further up
so f(n)=n+9 forall n>=9?
or am i doing concluding something too fast
I would compute at least two-three more values. we just saw that two values that followed the n+3 pattern wasnt enough
what are f(4) and f(5)
and what is f(27)
7 and 8 respectively
oh
f(7) is 12, f(8) is 15
pattern seems quite vague
f(27)=54
my current idea atm is just finding values manually till your close to the 1992 but idk if thatl work
call me crazy but
$f(x)=x+3^{\floor{\log_{3}(x)}}$
skissue.in.a.teacup
or maybe i am
clearly doesnt work for f(7) and f(8)
compute more values and hope that a pattern will pop out
im trying to figure out when it "jumps"
it jumps at 3, 9, 21 and im not noticing anything atm
it seems its linear up to some numbers then changes equation
given how the number 3 is important, maybe ternary helps
ternary?
base 3
o
Since it's mapping Z+ into Z+ and it's increasing we have f(4)=7, f(5)=8 , f(10)=19 , f(11)=21,... It seem like f(3n+1)=f(3n)+1 and f(3n+2)=f(3n)+2
It's just an idea idk if it will help anything
$$|x| = \begin{cases}
x & \text{if } x \geq 0 \
-x & \text{if } x < 0
\end{cases}$$
astraea 💫
honestly i cant have an idea on how to write this explicitly
like its recursive is it not
it doesent matteranyway since were not finding f
on proving it..
ohh wait i see it
.close thanks guys!
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the line y=5x-10 meets x^2-4x+y^2-32=0 at P and Q, find the distance between them
,rccw
where did i go wrong
youre missing a squared on the 4*68/26
why the square?
the circle has a radius of 6
so that sounds wrong
oh nvm it does go through the center
oh wait does it?
damn
sillying
yeah it's 12, I did it and got 12
the first thing i did was to write it in its square form but i didnt check it passing trough the center :(
Oh yeah, at second last step
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i thought it was the -b/a so i got rid of the -
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need an explanation
i got till the upper bound of A part
after that
idk
and whats sup A
sup(A) = supremum of A, a.k.a. the least upper bound of A
@grave kernel is the red underline the first part that's unclear to you?
nope, after the upper bound of A, i dont get it
i started with a small problem now im in a huge rabbit hole
okay now
what is least upper bound 😭
out of all the possible upper bounds of A, the lowest one.
the completeness axiom says this is always a thing assuming at least one bound exists.
- Let A = {nx : n ∈ N}.
- If (a) were false, then y would be an upper bound of A.
- But then A has a least upper bound in A.
- Put α = sup(A).
- Since x > 0, we have α - x < α,
- and α - x is not an upper bound of A.
- Hence α-x < mx for some positive integer m.
- But then α < (m+1)x ∈ A,
- which is impossible, since α is an upper bound of A.
can you name the earliest step in this breakdown that is unclear to you? @grave kernel
3rd one
axiom of completeness
if A has an upper bound at all, then it also has a least upper bound
oooooooooooooo
right
okay now alpha
is that
and alpha - x is not an upper bound cuz alpha already is the least upper bound
now
7th one
hows that coming
α - x isn't an upper bound of A, therefore there's some point in A that beats it
(and by "beats" i mean "is greater than")
it's the set of all positive integer multiples of x
yeah
okay
now
the rest
yeah
i got it
damn
thank you so much
thanks a lot
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need help
what happens if you plug 1 in?
!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.
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Don't they all have 3^n in them?
just factor out 3^n
@chilly gazelle Has your question been resolved?
got it thank you
let 3^n as Y
and solve it like quadratic
thats what we usually does
,calc 3 + 1 - 9
Result:
-5
this is it
Got it thank you everyone
?
!done
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prove that the set {1,2,3,4,5.....15} cannot be divided into 2 disjoint sets following these conditions. The first set contains 2 elements and the product of the 2 numbers must equal the sum of the numbers in the other set
i have proved it using mods but there were 4 cases to deal with
so i am looking for a better method
,calc 15*16/2 - 3
Result:
117
can say immediately the product of our two numbers must be at most this much
,calc 15*16/2 - 15 - 14
Result:
91
and at least this much
just find integer solutions for xy + x + y = 120
meaning that we can't have both of our numbers be smaller than 11
how does this happen
oh like x and y are our chosen numbers
got it
Hmm
add 1 to both sides and you can factor the LHS
SFFT 🥶
So xy=120 -x -y
since xy were chosen
(X+1)(y+1)=121
so x and y have to be same
which isnt possible
is this correct
yep
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im so confused what did I do wrong
the first function is wrong i believe
if i understand it correctly, the first function and your choice for its continuation are discontinuous
try evaluating the first function at x = 1
Do you not understand how to proceed to get the answer? or are you struggling to do the math?
like 1-cos pi x right
I got 0
nvm
yes, so not 1
Wait yea
lol
hang on
oh
1 - cos(xpi) for x = 1 is 1 - cos(pi)
what
how did you get 0
do it again
yea
cos(pi) is?
oh yea
cos pi = ?
no
2
ye
uh no
/2
nonono
exactly
no 1 is correct
-1
cos pi is -1
oh then i might have screwed myself over
Is B not right
ignore my very first message
check out the third one
is it -inf
no
😭
rlly
its almost 1
yes
ong
because top is positive and bottom negative
so first 3 limits are good now
I havent looked at the letters
oh
im not saying right or wrong, just walk me through the process
yes
?
oh type lol
No like
in order for the function to be continuous at 1 LHL must = RHL must = f(1) right
yep
3?
how did you get that
and if x -> 1?
Nvm.
lol
what
nah you're doing good tbh
🙇🙇🙇🙇
just few dumb mistakes, but its not like you're bad at math
i do the same all the time
ty 😭😭
so limit is?
-2
yes so you can put it with the right one
yes so number 2
since all the limits are different, there's only one answer
that’s right rifhr
yea lol
so thats ok
take your time
maybe
lol
yea doesn’t
🧠
-(1-x)
if x is greater than 1, 1-x < 0, but because of the absolute value, we just multiply by -1 to make it positive again
can you send the problem again, the original message disappeared i dont know why
oh
so you understood the limit of C?
wait so we just treat it as absolute balue first and sub in to see if we get engine or positive?
Negative
The
Ur
Ye
@vast loom here it is
if you have |x| where x <0 then it becomes -x
thank you
ohh
i was taught so poorly 😔
because you want the result to be positive
so -x is minus times minus if x is negative
ok so
and last D
2
:)
Omg
tyty, appreciate both of yall 🙇🙇🙇
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If we know a Boolean formula is satisfiable first hand, whats the way to find any one satisfying assignment
If you can simplify to a sum of product form, you're good
Just take any one of the terms, set the values such that each factor is true, and that's a satisfying input
Converting into sum of product form is not trivial
Problem is, even this isn't always easy to do
Yeah
what's the context for this? what scales are we working with here?
So like does the knowledge of a particular formula being satisfiable, give any hint into a not-so-convolutedly solving for any one satisfying assignment?
i may be mistaken but I'm pretty sure you can't beat regular SAT by a lot
? Can you elaborate
SAT is the complexity class for boolean satisfiability, which checks whether a formula is satisfiable or not
Basically like, if you have enough patience to convert into dnf, then you may as well not know of a formula being satisfiable or not, but if we know beforehand that a formula is satisfiable, will we be able to easily find one satisfying assignment
hmm
<@&286206848099549185>
Dppl algorithme ?
We already have an oracle for sat
We just need a way to find a satisfying assignment
Given that we already know the formula is satisfiable
(the other case is trivial, because if not satisfiable ,no satisfying assignment possible)
@lament citrus Has your question been resolved?
unless im missing something, you can either bruteforce it via truth table, or consider the subformulas and try to make each one true
We need the subformulas to be simultaneously true
Assuming we are in CNF, we need all clauses simultaneously true
yeah, so considering the original sentence, you can start with some options for a subformula, then narrow it down
e.g. considering $(P \wedge (P \implies Q)$, consider the subformula $P \implies Q$. Either
\begin{itemize}
\item $e(P) = e(Q) = \textbf{T}$, or
\item $e(P) = \textbf{F}$ and Q is whatever
\end{itemize}
but in the second case, then $P \wedge (P \implies Q)$ would be false, so we can narrow it down to the first case, and get something that satisfies the entire sentence
haseeb
so you are satisfying the entire sentence, but you break it down into the smallest subformula, then keep checking as you go up
I see what you're saying yes
Which makes me realise I made a crucial flaw in posing the question
And now that I realise the flaw, I realise the answer too
Thanks for this, but one question I have js
Is
lol i love when that happens
Isn't this justa slight modification over just brute force checking F or T
For every variable
We are doing brute force but also taking out impossibilities
basically, yes. i think there are some algos for checking with CNF, but they basically do the same thing (check each variable by clause and assign it a value one at a time)
but you are skipping some lines of the truth table based on what the sentence looks like
Also the question I should have asked was, if we knew a way to instantly know if any formula is satisfiable or not, can we easily find satisfy ing assignment and I think the answer to thta would be to set variables one by one to T or F, check the oracle, if unsat, flip, and move to next variable
Makes sense
And if sat, don't flip and move tk next variable
Anyway thanks a lot!
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hmm im not sure what this means, since every variable would need some kind of valuation initially, so that you can actually evaluate it
but if it works then 
The assumption is that we have an access to an oracle for finding out if any given formula is satisfiable or not
ohhh ok i see what you're doing
sub in e(P) = T for some P, check this "new sentence" for SAT, and continue
but im not convinced that you'd get a satisfying assignment at the end
Why not?
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Approximately 10% of adults in the United States are left handed. Out of a random sample of 500 adults, what is the probability that 12% or more will be left handed?
i'm genuinely so confused
i have no idea on how to start
i learned the central limit theorem and other basic things about sampling distributions from ap stats
but no matter how much i reread the notes and even the solution (this is a practice problem) i can't understand
First of all you need to identify the sort of distribution the left handed people will follow
What sort of distribution do you think it'll be
Why so
because you could identify the amount of left handed people as 'sucesses'
and also i don't see how the central limit theorem fits into this because that relates to means of several sampling distributions being approximately Normal
Correct
one thing i don't get how it fits in though
What does clt say
is specifying that the sample has 500 adults
ohhh
since the sample size is greater than 20-30 the sampling distribution is approximately Normal
Correct, and which theorem tells you that
clt
so then we can just do
hold on
how would i arrive at the standard deviation
if i'm using normCdf on a calculator
oh
sqrt((np)(1-p))
so it would end up being normCdf(lower = 60, upper = 500, mean = 50, standard deviation = 6.7082), right?
i checked the solution and it matches
thanks a lot
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Approximately 10% of adults in the United States are left handed. Out of a random sample of 500 adults, what is the probability that 12% or more will be left handed?
I solved this question by noticing that since n(p) and n(1-p) are both larger than 10 and n is larger than 30 we can assume that the sampling distribution is approximately Normal. To find the mean, I multiplied (0.12)(500) to get 60. To get the standard deviation, I did sqrt(np(1-p)) to get ~6.7082. With this, I performed a normCdf function on my calculator with the parameters lower=60, upper=500, mean = 50, stdev = 6.7082. This let me to get the same answer as is provided. However, the solution is different. They used mu sub p-hat = p to get the mean and sigma sub p-hat = sqrt((p(1-p))/n) to get the standard deviation. They then performed normalCdf(lower = 0.12, upper = 1, mu = 0.1, sigma = 0.0134), and got about the same answer as me. This confused me, as they used different formulas.
For the next question, when I tried doing it my way, my mean and standard deviation was wrong:
Candidate A and B are running for a seat in the state senate. The election results showed 75% voted for candidate A and 25% voted for candidate B. To confirm the results, recommend a
sample size that could be taken which would result in an approximately normal sampling distribution. State the mean and standard deviation you would expect to see in these samples.
What are the distinctions between:
mu sub x = np
sigma sub x = sqrt(np(1-p))
mu sub p-hat = p
sigma sub p-hat = sqrt((p(1-p))/n)
and how would I know when to use which? Furthermore, why do both methods lead to almost the same solution*?
*normCdf(lower = 60, upper = 500, mean = 50, sigma = 6.7082) is about 0.068018 while normCdf(lower = 0.12, upper = 1, mean = 0.1, sigma = 0.0134) is about 0.067779
Apologies if this question got a little wordy, but I've been really confused about this topic for the past few days
i realize now this is not concise
if there's a better place to ask this then please redirect me
i would ask one question at a time, you have two
i see
What are the distinctions between:
mu sub x = np
sigma sub x = sqrt(np(1-p))
mu sub p-hat = p
sigma sub p-hat = sqrt((p(1-p))/n)
and how would I know when to use which? Furthermore, why do both methods lead to almost the same solution*?
*normCdf(lower = 60, upper = 500, mean = 50, sigma = 6.7082) is about 0.068018 while normCdf(lower = 0.12, upper = 1, mean = 0.1, sigma = 0.0134) is about 0.067779
disregarding the candidate scenario entirely, would this be a more reasonable question to ask?
i don't know how to ask just 1 question about this because both of my questions are dependent on each other in this instance i feel
when approximating a parameter, mu_subscript indicates the expected value of the estimation
so would that be an approximation of the mean?
so I wouldnt expect to see mu_x, you sure you saw that? I would think it's more likely to be
$\mu_{\overline X}, \mu_{\mathbb {E}[X]}$
gfauxpas
i'm struggling to understand the difference between these 2 kinds of formulas
they should use capital letters
for random variables
$\mu_X$ is then simply the expected value for the R.V. $X$
gfauxpas
if that's the case then what's the difference between mu sub X and mu sub p-hat?
it's stupid to use a lowercase x because that symbol isn't introduced beforehand, so it's random, might as well use Greek letters or emojis
the way it's presented on the formula sheet doesn't make it seem like there's much of a difference
give me one moment while i see what conventions are used online
I don't like your worksheet
it's making questionable choices about presentation of the symbols
but I'll tell you what i think the sheet means
i can't do much about it sadly since this is the only sheet i can have out during proctored exams
so i have to get used to it
- $\mu_x$ and $\sigma_x$ surely should be $\mu_X$ and $\sigma_X$, there's no possible justification for using a lowercase x
gfauxpas
and it's telling you: these are the parameters of the variable X. X has mean blah and st.dev. blah
yeah that part makes sense
X has been introduced in the first line, but "x" has not been introduced at all
if X is some binomial distribution
now, when they say $\mu_{\hat p}$ and $\sigma_{\hat p}$
gfauxpas
they seem to be implicitly introducing a sampling process
yes but the sheet you showed me doesn't introduce the sampling until the line "if X-bar is the mean..."
it's defining the horse before the carriage
this is taken from an old ap stats formula sheet
also $\overline{x}$ is bad notation, because the RV's name is $X$
gfauxpas
anyway, what I think the sheet means is
if you were to treat this X as a sample of a larger distribution
then you are estimating p-hat with your sample
the average estimate of p-hat will be p
i don't really understand this part
if X is a distribution in itself
you're saying you're treating the distribution as a sample of an even larger distribution?
sampling from a distribution always creates its own distribution called the sampling distribution
yes
hmm
and in fact this can iterate
you can be sampling from a sampling distribution
likewise you're also using the samples to estimate the standard deviation of the underlying distribution that you're sampling from
the average estimation for the std. will be sigma_p-hat
why does mu sub p-hat equal p though? does it mean that the means of the sample proportions will be the proportion of the overall ratio of successes to total items in the sample
that needs to be proven, yes. i forgot the proof offhand
it's a theorem, not trivial
so mu sub p-hat would be focusing more on the probability of picking something from the sample?
uh
it's the best estimate of the underlying distribution's rate, given the information you collect by sampling
is how I look at it
if these 4 formulas are identifying different things, then how did me and the question writer arrive at the same answer when I used the formulas with sub X and they used the formulas with sub p-hat?
or should i ask that in another help channel
well that's not really a math question, that's a horoscope question
why is it that I tripped this morning but didnt fall
I'm glad!
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So Order of n of a mean a^n=e
and i know that O(a^p)
Gcd(p,n)=1
So O(a^p) is n
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Thats no math
Ples
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it's 100 but your reasoning is incorrect
connect the center O of the circle to P and R
you'll get a quadrilateral with angles (81x - 1) + (100x) + 90 + 90 = 360
ohh alr ty
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A bit off topic but it's kinda math
Why is this placement of 9 wrong in this sudoku game?
why did you think the 9 is there?
who's saying it's wrong though
there doesn't seem to be anything on the board rn that it's contradicting with
well it is highlighted red, which probably means it is wrong
is that the only spot on that column where a 9 fits?
nope, it can go to r9c3
Yeah
I think because both 7 and 9 are possible and there is no certainty of a single number yet. We can't say for sure?
You can try solving the other parts of the puzzle first
I think you just guessed there too early
or now that you know where 9 isn’t
Yeah this is it
Thanks
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So I'm pretty far into this question but I don't know what to do next. I know that $\triangle CDE \cong \triangle CBA$ by the cyclic quadrilateral property or whatever, and because of that, I've managed to deduce that $\frac{2\sqrt{2}}{3}CA=CB$. What should I do next?
747244351179980930
Hello guys, who have an idea to answer this
!occupied
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Plus you got your channel
Im new to discord and dont know how it work, my bad
all good
hmm
An observation I see herr is that AE and BD are altitudes of the big triangle
oh yeah
so we get AE/BD = AC/BC
I noticed that those were right angles by thales but I didn't think of them being altitudes
then you might confine those into the right triangles inside the circle
set up equations
idk if it'll work or we just end up with what we started
how do we derive this?
what property tells us this?
1/2 AE.BC = 1/2 AC.BD = area of the big triangle
haven't tried it on paper tho
OK here's a thought: if BD is an altitude of triangle ABC, then by Pythagoras AD^2 + DB^2 = 30^2, and DC^2 + DB^2 = CB^2
but you can express both DC and CB in terms of AD
that's a good point
So you should end up with two equations in just DB and AD
I am hoping that they are not just the same equation...?
I think (?) AD = 6√(5)
But I did that pretty quickly so plz confirm
the system I have is $AD^2+DB^2=900$ and $(2AD)^2+DB^2=(\sqrt{8}AD)^2$
747244351179980930
yes agreed
747244351179980930
right?
I got same
30 60 90 0:
I don't think it's a 30-60-90
nvm it's not 30 60 90
because DB is not a hypotenuse
but we can get those sides nonetheless
I'll just substitute $DB=2AD$ into the second equation
747244351179980930
ad=$sqrt{180}$ I think?
747244351179980930
good for me lol
and then there's just heron's
I guess
might be easier if I like prime factorize everything when doing it
let me get the side lengths first
ok so I got $CA=18\sqrt{5}$, $CB=12\sqrt{10}$, and obviously $AB=30$
747244351179980930
agreed
I mean tbf, though unused, it is an aime problem
so theoretically it should take time
there's probably a better way though
Are you looking for solution in closed form?
yes most likely
closed-form?
as in, not a decimal approximation
Normally I would say this is that time to break out your calculator
yes
but then you will get decimal approximation
well it's an aime problem so it has to have a solution from 0-999
unless the rules are different because of it being unused
so it has to simplify to something nice even if the process isn't pretty
OK, I see now, you don't have to use Heron
AC = 18√5
DB = 12√5
Area of triangle is 1/2 their product since DB is an altitude
thank god you saw that
I was genuinely about to start using heron's
alright
hey and the sqrt(5)s cancel
or not cancel
whatever
$18125$
747244351179980930
See you have to be lazy and unwilling to work like me otherwise you will not look for shortcuts hard enough 😄
thanks @civic gazelle @hidden turret
no problem
happy to help
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Find the value of 5xy - 3zy if (x + 2y + 4z)^2 >= (5 + 4y^2)(x^2 + 1 + 4z^2)
I dont know where to begin here
I'd start with playing with the terms, maybe expanding or moving things from one side of the inequality to the other
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Is this for a specific class? There could be a topic specific method
Yea im thinking smth like that
im trying to make them somewhat factorable >= 0
like smth + smth + smth >= 0
i got this
Just remove brackets
Oh nvm you couldn't
What about just tryna factor out all the X,Y and Z
And leaving only numbers
thats what im trying to do
@neat silo Has your question been resolved?
Okay I found an answer using a very non-algebraic method
I tried plugging the inequality into desmos, and after fighting with it for a while I managed to nail down a point that satisfies the inequality
idk if it's the only one, but there is at least a answer
ss it please
I got like x = z and x = 1/2y
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x = y = z = 1/sqrt(2)
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why in this question we multiplied with 100 then and not in the earlier question...
(both questions are slightly different)
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$\frac{1071.20}{6.5%}\cdot 10%\cdot 5$ ?
Denascite
8240
I accidentally deleted the pinned message..so..
did you get why 1071.20/6.5 is multiplied with 100
they ask for principal directly
i know only this way..i get why they did this here..
but
does it matter?
look, if you want to explicitly find the principal and you feel that you have to multiply by 100 for that
you can do it
nobody is forbidding you
i am not your mom, i cannot stop you from multiplication by 100 like it's something illegal or dishonorable
yes you are not..
i just had a doubt
will the answer be 8240 x 100 =824000
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if a simple graph has some odd vertices, how do i show that there are 2 vertices with an even number of common neighbours?
@rugged vine Has your question been resolved?
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Yes good application of .close 
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may sound dumb but for parts c,d,e are we allowed to assume that the inverse exists (and thus f is bijective)
@obsidian cliff Has your question been resolved?
oh
wait what
oh fuck me time to redo all those exercises
whats the difference
well for starters the inverse doesnt have to exist....
the inverse is still a function
the preimage of a set is a set
right
ok
my bad
sorry i forgor that $f^{-1}$ does not necessarily mean the inverse
lifelong dumbass