#help-17
1 messages · Page 11 of 1
I meant y
,w sin(ln((-1)^2+0^2-2(-1)+1))

I have done something wrong then I think because when I paint up this function in 3D GeoGebra I can just tell by eye
that I do not cross it
Which is a really bad argument haha
But in your wolfgram example you use x = -1
Oh oops
You had it right
I made an oopsie
out radius is 1
so it should not cross y axis
Oh nice
Thank you so much really you have helped me a lot
Could you just summarize what we did so I can get a deeper understanding?
you're trying to find all the $(x, y)$ that satisfy $f(x, y)<0$
SWR
Or, more specifically,
So you need to know when sin<0, which is in all intervals (2π(n+1/2), 2π(n+1))
So you find
"for all"
Ah and then we have this inequality and we want to "place" it as close to the point (0, 0) and therefore we chose n = -1 because we cannot chose something like n = -1/2 for example
How did you however simplify (x-1)^2 + y^2 = 1
Since you write e^-π < 1 < e^π
omg
wait
dont even answer
bruh im so slow
haha
we chose 0,0

nvm that its late for me xD
And then we have our intervall where we have the answer
And then we just write out the radius
making a "donut"
Where the donut showcases all the negative values of f(x,y) close to the point (0,0)
@hushed pewter Thank you so much, really really appreciate it
"negative values of f(x, y)" is technically okay, but imo sounds kinda weird. I'd say "all (x, y) near (0, 0) where f(x, y)<0"
Ah ok
get some rest
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How do i go about solving this problem? It is my understanding that the normal vectors of the 2 planes should have a dot product equal to zero but i do not know how to find the normal vector of plane 2
i know that my normal vector for plane 1, n1 = (2,-4,6)
but past that i am stuck
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Can someone help me see what I did wrong
I'm not getting the right terms
I just assumed the center is 0
Cause otherwise idk how id do it
Because I have fraction on top divided by a factorial so i move the factorial on top
Like this
There's a difference between $\frac{a/b}{c}$ and $\frac{a}{b/c}$
SWR
I dont understand this
Thats just the same thing rewriten
Im saying you rewrote the same thing
in both texts i just dont understand what it means
2
yes
I think
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are you aware of exponent rules?
Is this channel available
you can see that $3^{x+2}$ has a sum in the exponent
Talent Unlimited
x^(a+b)=x^a+x^b
so you can split that into two terms
Yup
$$ 3^{x+2} = 3^x \times 3^2 = y$$
So 3^(x+2)=3^x+3^2
Talent Unlimited
Yup
And 3^2=9
So I’m confused on how to solve
from this you know that 3^2 is 9
So 3^x=y/9
so just transpose that to the right hand side
$$ 3^{x+2} = 3^x \times 3^2 = y$$
$$ 3^x \times 9 = y $$
$$ 3^x = \frac{y}{9} $$
Talent Unlimited
Yes
It's being transposed from the left hand side
You divide both sides by 9
Why 9?
Since 3^2=9
Is there an example that explains this with just plain numbers
Yes but
Why divide by 9
Is this an algebraic rule
because the question is asking to show $3^x$ in terms of $y$
Talent Unlimited
@digital shell
"in terms of" means representing a particular thing using a particular variable
yeah
in this case representing $3^x$ using $y$
Talent Unlimited
Oh
So does this mean to keep 3^x and y
And j algebraic ally simplify the other parts
Algebraically
it means that one side of the equation will contain $3^x$
voiceless
basically yes
and the other will contain a expression containing the variable y
yeah pretty much
any other questions?
@digital shell
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Good morning gents. What that sign means?
its Discrete Math btw
phi can mean a lot of things
oh lol np
thanks a lot,solved!
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-8/7 = slope , 5/7 = y intercept
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don't ping helpers until after 15 min
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have you tried drawing a picture? seems like it would be helpful here
oh, i had thought that the 60 and 40 referred to the outer rectangle's sides, not the inner rectangle
i might be misinterpreting the question tho
actually after reading again i think yours is probably right
Lol perhaps
i guess try it your way and see if you get one of the answers haha
So I used the equation;
(2x+60)(2x+40)=666-2400
4x^2 + 200x + 2400 = 666 + 2400
4x^2 + 200x - 666 = 0
2x^2 + 100x - 333 = 0
And then I'm stuck
We aren't supposed to use the quadratic formula
The entire tablecloth + the lace
ok, let me read over your work now
Just a typo
yea so far i agree
and now because we are lazy we appeal to wolfram alpha haha
,w 2x^2 + 100x - 333 = 0
Okay, I can't find the numbers that multiply to -666 and add to 100 😦
Hmmmm
With the level of work I'm doing, it should be at most a fraction or whole number 😭
hmm, that doesn't match any of the answers
maybe my interpretation was the right one then
I'll try it
Okay I got
(60-2x)(40-2x)=666+2400
Which simplified to 4x^2 - 200x - 666 = 0
wait shouldn't the RHS be 2400-666
Which still have no even factors
in that case
Ohhh yes
,w 4x^2 - 200x + 666 = 0
ugh, or we're both misinterpreting
would have been cool if the teacher had provided a picture haha
hmm alas i'm out of ideas
I see
hopefully your teacher can clear it up
Thank you for trying
cheers
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anyone in calc 3 know how to do this? im not sure where/how to start
also, part b) should say 6a and not 4a
Start by parameterizing the ellipse-disc
I was thinking more of a direct parameterization, but that also works
Actually that works fine
But uh
Personally I'd parametrize the ellipse-disc directly
Because then the jacobian requires little thought if you're familiar with them
yeah im familiar with doing that part but im not exactly sure what paramterizing is
wouldnt the jacobian be easier the way allarkvark did it
Like parametrics
this was a different one but similar
Well if you're familiar with Jacobians
Personally I'd rather go with an ellipse
There's a neat trick about Jacobians
If x = au cos(v) and y = bu sin(v), the jacobian is just (a•b)u
That's why I personally like to parametrize an disc
how would i turn the ellipse into x=au cos(v) or y=bu sin(v)
a is the radius in the x direction, b is the radius in the y direction. You let u go from 0 to 1 (which should be clear as to why, since you gotta go from 0 to the full length of the axes) and v go from 0 to 2π
parameterizing when u just set a variable to another or after u solve the integral
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could I say for this when a/b are put into simplest form such that a and b are co prime, and the denominator (b) is a prime number greater than 2, or a multiple of a prime number?
a terminating decimal can always be expressed in the form a/10^n for some n
where a and n are integers
oh no i meant if b is not a prime number (aside from 2) and not a multiple of a prime number
my bad
so like 1/12
12 is a multiple of 3 though
any number is a multiple of prime number, that's just composite, there's no third type
i know. So something like 1/12, and since 12 is a composite number that is a multiple of prime number 3, 1/12 must be non terminating
1/8 is terminating because 8 it not prime, and it is not a multiple of any prime number (with the exception of 2)
ah ok
did i just word the criteria poorly?
yikes lol
now i see Bungo's criteria. Is that like the universal criteria?
oh wait it makes sense actually
that's pretty cool now that i think about it lol
sorry, i got distracted... i was going to follow up and say, if you start with a/b in lowest terms (coprime), then if b has any prime factors other than 2 or 5, it's not gonna have a terminating decimal expansion
otherwise it will
no worries, im just grateful to get any help at all. But now i feel like my original criteria might need to be completely scrapped, but 1/15 is non-terminating
yea for 1/15, the denom has 3 as a prime factor
there's no way to get that into the form a/10^n where a is an integer
basically as long as the denom only has 2's and 5's as factors, you can multiply num and denom by either powers of 2 or powers of 5 until the denom is a power of 10
right, thank you so much!
sure, cheers!
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,rotate
what did I do wrong
I checked wit the integral calculator and this is the difference
I cant seem to find the error in my work
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😭
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for 1d)
Is the answer: As ln > 0 and the quota is not 0, {(x,y) belongs to R2: (x,y) is not (1,0)} , so the function is continous in its domain
?
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Hey, I am very confused by this factor, can someone tell me what was done between these equations
put this on a common denominator
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Umm hello i need help evaluating this piecewise function
Idk how to figure out which one to use in the question 16
wdym "which one to use"?
It’s kinda hard to explain but like 15
which of the three function values are you having trouble calculating? f(2), f(-2) or f(-1)?
Ah shoot
I thought it was a whole thing
Since there’s no comma
But the answer is just -2..
Whilst question 15 it was 3 different set of answers
yeah bc you're asked to calculate one number and not three numbers.
but calculating f(2)-f(-2)+f(-1) requires some steps, of course
Ah shoot bruh
you need to calculate f(2), then calculate f(-2), then calculate f(-1), then subtract and add them as written.
Yes I just realised so basically its just algebra oops alright thanks
Yes I’m dumb I just realised what you said
Nobody saw
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do pentagons always have the same angles if all sides are equal in length?
No
I believe that applied to any n-gon with n > 3
Because for quadrilaterals there are rhombi
They have equal sides, but angles are not always equal
so if the angles are less than 180, it is a regular polygon
Can't think of a counterexample, so yes, I suppose
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✅
One came to my mind
Draw a square and an isosceles triangle on top of it
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can i get some help
2 to the what power equals 128?
7
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The denominator of a fraction must be equal during addition or subtraction for two fractions to be added or subtracted in the first place
The denominator does not change in addition or subtraction. Only the numerator
Maybe an example will help?
So if we take 2 fractions like the following: 3/5 and 4/7
How would you approach adding these two?
I wanna see how you'd approach this first before going into further detail
Do you know why are you making the denominators equal?
So basically what you've explained in that is exactly why you make the denominators equal
lcm of the denominators works or just multiplying either fraction by the denominator of the other in order to make the denominators equal
Depends what you mean by that?
Maybe you need something visual
If you add 3/5 and 4/7 without making the denominators equal you'd get 7/12. 7/12 is not the same as 41/35
This denominators are already equal, so you can add or substract right away
Additionally you can look at it through decimals
Let's say we have 1/4 of a pizza and 1/2 of the same pizza if we add it it becomes 3/4 of the pizza rather than 2/6 of the pizza
Here you have one example where you can't just add without making the same denominator, and you will see the reason why looking at the size of the parts
1/3 of a whole is bigger than 1/4, so to add them both, you must make them to be equally big
You can do them equally with a bigger denominator
for example: 1/2 is equal to 2/4
so if you have to add 1/2 + 1/4, you can make 1/2 = 2/4 and add them up
2/4+1/4 = 3/4
you are multiplying by 1
for example
2/2 is = 1, right?
so if you multiply 1/2 * 2/2
you get 2/4
and because 2/2 is = 1, that means 1/2 * 1 = 2/4
so 1/2 = 2/4
because multiplying by 1 is like doing nothing
it's just a transformation of your number into something you want
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i am very confused on how to do the following q
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So what is p if not 6?
black_couscous
$\sqrt{n^6} = |n|^3$
Frosst
But here n is positive
n is positive so the absolute value doesn't matter
i am blind i better sleep
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how do i
you can use whatever software/method you are comfortable with
I don't use excel, so I don't know sorry
okay no worries i will scour my notes
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How is this looking
I am not sure if simplifying the power is a legal step like I did
(Getting rid of the 2/n)
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you might need to repost since this channel is closed
Okay
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how do i figure these out from the top determinant
Do you know how each row operation affects the det?
i forgot how the sign changes
but do i take the 2 out
multiply by 3 and take the negative out
That's useful
If I'm not mistaken, column operations do the same too, so you can take the 2 out of the colum, instead of the row
they do
what’s the rule for multiplying c2 by 3
It's the same as row operations, if you multiply a row by a constant, it scales by that, same logic with columns
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Hey, is this proof right? My professor gave an easier proof, but this is what I came up with. I feel like something is up with the substitution.
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is the remainder thing for series ( ∫n+1 < Rn < ∫n) the same for alternating series?
do you have an actual problem you're working on?
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wym
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hello, I have a problem. for context, i am writing a small programming project that involves a little bit of angle work.
into the question. I have been trying to find a function to "convert" "unit circle" degrees into "compass" degrees. (see diagram below). I've tried a ton of things but my brain is seriously fried. I've been thinking of a solution since sunday. please help!
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@vast shale Has your question been resolved?
Did you try a piecewise function y=90-x for [0,90] and so forth for each quadrant
are you allowed to import packages?
there should be something in almost every language to do that for you
i think i could also come up with a solution in Java you could build your solution off of let me take a look
could you give me an example of a conversion on a piece of paper or soemthing im not sure what you are trying to convert from/to
(450-x)%360
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ANOVA: Does it have to be categorical?
My understanding is, that it can be used to analyze any model right?
Just simply replace the $\bar{y}_i$ with the model prediction, right?
BeatriceBernardo
I'm using this as a reference https://www.itl.nist.gov/div898/handbook/prc/section4/prc421.htm
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,rotate
,rccw
well
you know from (a) that it's 125/4 m above the ground
you know the acceleration (due to gravity) is 10m/s^2
you should know how fast it's initially moving vertically
that should be enough information to work out how long it will take for it to hit the ground
@inner lodge
i know
i have the information
but im not sure what to do with it
its moving 15m/s initially i worked out
im not sure what to do as it "bounces"
huh, that's... not what i expected
is that 15m/s up or 15m/s down?
i think you just ignore any bouncing and work out how long before it hits the ground for the first time
oh wait you mean at the time when it's thrown?
yep
i meant "initially" as in "at the start of it falling after hitting the wall"
ohh
so would i solve for the vertical displacement eqution equal to zero first
i got that it hits the ground again at t=4 in that case
...i don't know which equation that is
um i worked out another equation
so it gave -10 m/s^2 initially for acceleration
integrating i got -10t+c
where i subbed in the initial conditions
where i got the velocity as -10t +15
and similarly doing the same but subbing initial conditions with t=0 and y=20 since it is starting 20m above origin
giving -5t^2+15t+20
...yep that sounds right
although the question they asked was how long does it take after rebounding from the wall, not from after it's thrown, so you'll need to adjust that time a bit
it hits the wall at t = 1.5 i think?, so just subtract that
would it be 2.5?
t=2.5?
since time of flight is 4 seconds
and it hits the wall at 1.5
yep
which also agrees with what i got by a slightly different method
i just thought "well, $\frac{1}{2}at^2 = \frac{125}{4}$ where $a = 10$" and solved that and you get $2.5$
bee
well for (b) this is just the answer
yep
now that you know how long it took between hitting the wall and hitting the ground, and how fast it was moving during that time... :)
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$(1+\frac{1}{k(k-1)})^k>1+\frac{1}{k-1} \to \sqrt[k]{\frac{k}{k-1}}<1+\frac{1}{k-1}-\frac{1}{k}$
Quasar
Is the first inequality somehow famous?
cz someone just used it to solve the below question.
[\sum_{k=2}^n\sqrt[k]{\frac{k}{k-1}}<n.]
Quasar
i mean thats just comparison test no?
$(1+\frac{1}{k(k-1)})^k>1+\frac{1}{k-1} $
Quasar
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
you kth root both sides to show this
and apply comparisson test on the series
or i guess the order perserving property of sums
I meant this one.
The problem is to prove this
The question is that and below is the solution lemme write wait
i think they see that kth root and come up with a way to prove its always less than one
$(1+\frac{1}{k(k-1)})^k>1+\frac{1}{k-1} \to \sqrt[k]{\frac{k}{k-1}}<1+\frac{1}{k-1}-\frac{1}{k}$
Quasar
$\sum_{k=2}^n\sqrt[k]{\frac{k}{k-1}}<\sum_{k=2}^n (1+\frac{1}{k-1}-\frac{1}{k})=n-\frac{1}{n}$
Quasar
yea
yea
cool.
like its fairly standard i think
.close
.close
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<@&286206848099549185>
ok, how do i cometo that tho
wait no i cant do that i think
Ye you're right
or can I
cant you choose $\delta=\frac{2\varepsilon}{|x+c|}$
llspacebarll
I thought I cant just leave it like that
idk i think i can
then you jsut work backwards
and you haev the required implication
this just means that the function is not uniformly continuous
its just regular continuous
wait why is it 2epsilon
cause you multiply 2
isnt it suppoed to be epsilon/2(x+c)
you have a typo
i dont think that this works actually
i think delta cant depend on both c and x
just on c
ye thats what i was thinking
use the triangle inequality on |x+c|
idk what that is
why
You want 1/2 |x-c||x+c|<eps
|x-c|<delta
|x+c|=|x-c+2c|≤|x-c|+2|c|
Ande then you say |x-c|+2|c|<1+2|c|
why is |x-c| < 1 tho
Because we chose delta=min{1,2eps/1+2|c|}
Means Delta ≤1 and delta ≤ that other thing
ye why did we choose this tho
from what conclusion
Usually when we have a quadratic in delta like here we choose delta to be min{1,something} that something you figure it in the end
It can be really any number not 1 but it's easier if 1
Learn more about epsilon-delta definition of a limit from Brilliant via https://brilliant.org/blackpenredpen/ . That link also gives you a 20% off discount on their premium subscription.
Today we will see one of the hardest parts of calculus, the epsilon-delta definition of limit. More specifically, the epsilon-delta definition of continuity. ...
Watch this
ok ty
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Construct an acute triangle ABC (AB < AC). Construct altitude AH and median line AM. Draw D and E
so that H is the midpoint of AD and M is the midpoint of AE. From M construct MN so that it is
perpendicular to DE (N belongs to DE). Prove: MN, BE, CD all intersect one point
I have an idea
Call the Intersection of BE nd CD O
And prove that angle BOM = EON
but i dont know how to approach it
or maybe prove thatt ON is perpendicular to DE
but
i still have no idea
Note: no pythagorean, circle, quadrilateral, trig theorems
pure triangle theorems are only allowed
and thats the difficult part rlly
trig is triangles what?
what?
trigonometry is the study of trigons, i.e. three sided shapes
what do you mean by this
Does this like relate>
?
I mean that "pure triangle theorems" excluding the pythagorean and trigonometric theorems makes no sense
i mean
i dont know english very well
pure theorems as in
congruency, altitude intersection, median line intersection, bisector intersection, etc
idk how to explain
it looks to me like the intersection point is a center of triangle DME.
which center
because i cannot spot orthocenter, center of gravity, etc
...no it isn't, it's the study of trigonon metron (τρίγωνον + μέτρον), "triangle measure"
which mostly refers to stuff like sin and cos, not just the study of triangles in general (i don't think there's a specific word for that)
dunno, that's what needs to be figured out
Maybe I can prove O is an orthocenter
oh wait i dont
the word for it was historically trigonometry. The reduction to the angle functions we're used to is a recent phenomenon, but is still based in triangles.
bc it requires ON to be perpendicular to DE or BC
is this... exactly related?
no, sorry.
its not your fault really
you may be able to do so. You know that triangle AHM is right, as is ADE. When in doubt, just construct as much new information as you can.
hm
I can prove BE is perp to MD and CD is perp to ME if that was the case
but it seems a bit unfeasable from what I have seen
you may want to use the fact that AD and AE are both bisected by BC
this implies that AHN~ADE
(you might need some more rigorous steps to get there, but that's a basic idea)
Wait
I have an idea
Maybe prove N is the midpoint of DE
=> N1 = N2 (the angles of N)
=> N1 = 90
by hopefully proving MDN is equal to MEN
by s-a-s
I think I have a direction as well, prove triangle MDE is isosceles, then, since M is the midpoint of BC, BE=DC by symmetry. Also by symmetry, they should meet on the altitude of MDE (which is MN). I don't remember the theorems that get you through this, exactly, since it's been a long time since I've done this, but it should work out
oooh
well
i think its like the same to MDN = MEN
just more convenient
it should be
And AB//CE
also BD = CE and CD = BE
these kind of rigorous prooofs are asians staple
they're common in US geometry classes as well
i mean
grade 7,8,9 is ALL proofs
we dont learn pythag until late grade 9
they gotta make life insanely hard for us
arguably that makes things better. Learning these proofs first makes trig easier once the pythagorean theorem is learned. You get special triangles naturally from these kinds of constructions
couldnt they just like move pythag down one class
it makes calculation problems easier
anyways
its going offtopic
just use these proofs to construct the pythagorean theorem, then you're allowed to reference it as a lemma
in vietnam there is no such thingss as a lemma (until g10)
we only are allowed a set of rules
you have this, now follow it to tooth and nail
you do have lemmas, you just don't call them that. You proved that BD=CE, that's a lemma (thing proven from the given rules that is used to prove other things).
hmmm
how do you even say it in english
like BD = CE is only specific to this problem
and proving general theorems dont get applied
yes, but it holds for all possible cases where this problem applies. Lemmas are usually more general, but they're just stepping stones
ah i understand
i was going to ask another question after this but this most likely answered it
so
heres my proof
we have AH = AD and BH perp AD => ABH = DBH
AC // BE => DBC = ACB; AB // CE => ABC = BCE
=> ABH = DBH = BCE
Evaluate Triangle BMD and MCE:
BM = MC (midpoint)
MBD (DBC) = MCE (BCE)
AD = CE (proven above)
=> BMD = MCE
=> MD = ME
=> MDE is isoceles => MDN = MEN (angle)
Evaluate triangle MOD and MOE
MD = ME
DMO = OME (corresponding angles of equal triangles)
MO: Shared length
=> MOD = MOE
=> MDO (angle) = MIO (angle)
Because MDN = MDO + ODN; MEN = MEO + OEN
=> ODN = OEN
=> OD = OE
And Triangle MDN = MEN (similar to MOD and MOE)
=> DN = NI
Because OD = OE and DN = NI =>
ON perpendicular to DE (theorem)
BC MN perpendicular to DE and ON perpendicular to DE
=> MON is on a straight line
Because O is the intersection of CD an BE
=> the three lines intersect at O
@solemn storm correct?
be careful, AH=/= AD, they are colinear, not equal.
something here isn't matching up in the first half of the proof. I'm not strong enough in this to exactly say what though
really
can you tell me like the zone of the first half
like is it the triangle proof
or the parallel proof
something about AC || BE doesn't seem obvious to me. It may be a typo
oh
I proved it in question a0
A)
this is D)
i think i said it to you earlier
.
ok, if you've proven it (therefore it's a lemma), then that seems good enough
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hi is it possible if I can ask math questions involving finances here
I’m just going to send the question here anyway
If I’m finding the capital gain, it would be:
RM 900000 - RM 54000(10% down payment) - RM 15000 - RM 8000 - RM 18000 - RM 666000
But why can’t I include the original price in the deduction?
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Hi, can anyone help me with this question please
@prisma viper Has your question been resolved?
do you recall what is three-figure bearing?
@prisma viper Has your question been resolved?
yh, i do, but im confused about how it works with vectors
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since these digits are just 0-9
im not quite sure why we can be sure that y isn't equal to an already defined xn
because, by construction, y has atleast one different digit to every xn
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why is d/dx wrote as a fraction is there a reason why its written in this specific way?
in the most simple interpretation its meant to be the infinitesimal analogue of "change in function/change in x", usually written $\frac{\Delta y}{\Delta x}$
ΣAC
its not really a fraction, but for nearly all cases you can treat it as such
and then eventually you discover that in fact it really is a fraction, of things called "differentials", that are a fairly advanced thing
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henlo,
$\nabla u \cdot \nabla v = \nabla v \cdot \nabla u$
fuli
this is true right?
dot product is symmetric yes
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I apologize
@fresh wing what have you tried?
the simplest answer is very simple don’t overthink just try some stuff
*some rationals
1/3+1/4+1/(12/5) 
nice lol
where does it say that
Someone told me that

No, seriously lol
No one told us 
lol they didnt mention that x has to be integer
dang
find how many sets of nonrepeating integers from 2 to 2023 have inverses that sum to 1
hard q
What is this from?
true but that doesn’t make it possible to cheese bc integers are just as easy
It reads like a #competition-math problem, but it's pretty amateur hour to neglect mentioning x be an integer
Idk, one of my friends said it's an interesting problem so I thought I'd try it
I don't think it's a competition one
Best I can think of is the one easiest solution, and then solving computationally
The 2023 screams competition math
Yeah, we are allowed to use a computer and program
Thats quite important info
Well my friend told me he used one
probably an olympiad problem
You need to tell us these things
brute force
Lol
I can read minds, but you're out of range. So just tell us
I tried programming and I got 43 values
it should be around 2023*2023 loop so it should execute in no time. Brute force is best approach
2023!
I'm not that good at programming
You can have more than two fractions
oh dang, im idiot
Brute force is checking all possible fraction combinations
This sounds like dynamic programming
I hate dynamic programming. They take forever to set up
The answer is a solution strong?
wait wouldnt it actually be 2^2023? For each number you either include or dont include it
String
Ah I believe you are right
still too slow tho
if you have 2 sets of coprime integers that have a sum of 1, where the greatest values have a product less than 2023, you can multiply them
bc 1*1 = 1
might help
you can also prune in the sense that if you tested a set of integers that reciprocal summed to something bigger than one, you wouldnt test any sets that contain that set as a subset
sounds annoying though
What would that look like?
painful
yeah i dont know how to implement it, or if its even useful
What's annoying is need to do fraction math in programming without floating point error
So you gotta make a fraction struct
And, there's a possibility to go above 64-bit, so you gotta add a BigInteger struct too
There's a lot of work in this problem
What's the time frame?
alternatively if for example you're looking at 3 integers, $\frac{1}{x} + \frac{1}{y} + \frac{1}{z} = 1 \iff yz + xz + xy = xyz$
ΣAC
so you could avoid floating point
it’s definitely less than 1280 because the lowest 1280 values sum to >1
not that helpful
Won't we need a loop inside another for loop, an array to keep the correct rationals in, and some common sense?
we will need some common sense
I also claim there are no multiples of primes greater than 404 because their inverses have to add up to something with a numerator not divisible by the prime and 1 + 1/2 + 1/3 + 1/4 + 1/5 (or some subsum) has denominators less than 404
not 100% sure on that
@fresh wing Has your question been resolved?
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How do i solve these?
Sum of exterior angles?
if ur asking if thats the type of problem idk, i think?
the assignment is js labeled lesson 12 so 💀
Sum of exterior angles is always 360 degrees no natter the size of the polygon
so then i'd have to add up all the other numbers and the number thats missing is the answer?
the sum of all the exterior angles, i.e., the ones given, is 360º
ohh okay ty
wait so for the third one how do i solve it since theres 2 x's, do i have to give 2 answers or? 😭
@vague oriole Has your question been resolved?
No
solve for the exterior angles as normal by using 360- all the angle values and then set that equal to the missing value, say for example if the missing angle is 40 set it equal to 2x and solve dy dividing both sides by the coefficient of x (in this case its 2).
oh got it, ty!
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number 56. Im confused on how to write the summation because the deposit period isnt the same as the intrest period
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What am I doing wrong again