#help-41
1 messages · Page 61 of 1
somehow it's eqaul to this
how is the sqrt negative wtf
maybe it's a mistake what do you think
Incase of 1, 0 and fractions the square root will not be negative
Are you sure x is bigger than an ineger but smaller than a fraction?
ohhh my bad but that's not the problem that i'm talking about
$0 \le x \le 0.5$
RulzerFly
yeah this
i replaced the 0 with a 1 without knowing
but still it gives me the same results
this
instead of
The difference is the sign and place of the 1/2, review the process and see what are you doing with it
can i show how i got it ??
tbh im not very familiar with this, but it’s generally good idea to show it
$y^2 + x^2 = y \Rightarrow y^2 - y + x^2 = 0 \Rightarrow (y - \frac{1}{2})^2 + x^2 = (\frac{1}{2})^2$
RulzerFly
so this is a circle with a center of (0, 0.5)
so we're trying to get the part colored with red
so we write y in function of x
it gives
$(y - \frac{1}{2})^2 + x^2 = (\frac{1}{2})^2 \Rightarrow y - \frac{1}{2} = sqrt{\frac{1}{4} - x^2} \Rightarrow y= sqrt{\frac{1}{4} - x^2} + \frac{1}{2}$
$(y - \frac{1}{2})^2 + x^2 = (\frac{1}{2})^2 \Rightarrow y - \frac{1}{2} = \sqrt{\frac{1}{4} - x^2} \Rightarrow y= \sqrt{\frac{1}{4} - x^2} + \frac{1}{2}$
RulzerFly
look
The only confusion i have is, where did the the parentheses (y-1/2)^2 come from
just to get a circle equation
i think i found where i'm wrong
the squared
look
$y - \frac{1}{2} \neq \sqrt{\frac{1}{4} - x^2}$
that's the problem
RulzerFly
it's abs
and the red part is the bottom one
so
$y - \frac{1}{2} = - \sqrt{\frac{1}{4} - x^2}$
RulzerFly
RulzerFly
like the solution
I be real
I was genuinely gonna advise some general stuff, but you went through the work again and got it
Seems you got it with no help anyway 
it's easy i'm just dumb :skul
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What help
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Anyways, good ya caught on your mistake
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Hi there!
I started studying Boolean algebra and it's still very confusing for me.
Do you think I wrote down the expression right?
sure
yeah
Thank you! I will try to tackle the simplification, then. 🙂
@glossy arrow Has your question been resolved?
What do you think, am I on the right track?
<@&286206848099549185>
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find the area bounded by the curves y=sec^2x -1, y=8cosx-1 and the line x=pi/4 for the domain pi/4 < (and equal to) x < (and equal to) pi/3
what have u done so far
@ebon temple Has your question been resolved?
like i lwoeky kind of forgot
how to do it with three functions
@ebon temple Has your question been resolved?
maybe revising first is better then, do you remember how to calculate the area under a curve above the x axis?
yes
then first plot the curves
ig you can use desmos
can you tell what is the area you need to calculate?
uhmm
?
wait do i need to care about x=pi/4 at all bc the bounds
r already like
yeah turns out you don't need to
even without the bounds i think you can figure out the bounds yourself
@ebon temple Has your question been resolved?
think its a little easier to imagine it if you use trig identity 1 + tan^2(x) = sec^2(x)
basically graph of tangent but everything is positive
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Help
The first is the question and the second is my attempt. I am not a math student so I am very clueless about the rigor, please help me
Mighty @patent raptor
Help me, I am really bad at math and have absolutely no clue if I have done it right
Anyone please help me
i'm kinda confused by ur working layout
Which part I can explain ☺️☺️
btw ur answer isn't quite correct, g'_n doesn't converge uniformly
Bcs im not really math student and this is my hobby so the layout can be pretty messy
yh that's valid
On [0,1] though
yeah no it doesn't converge uniformly
we'll get to that
this explains it huh
It doesn’t converge uniformly on [0,1] why though?
i think as a general principle, it's kinda to deciper ur work cus you have to prove several parts and it's not entirely clear what each part of your work is trying to prove - a good way to present your work is to do a claim-proof structure
so Claim: "stuff"
Proof: "stuff"
then what u've done jumps out a lot more
anyway that's just some general comments
Yes that’s true bcs I ain’t trained in that sadly
i mean if ur not studying maths it's impressive ur doing this lol
Is fun
i think some more words would be good to explain why g_n -> 0 pointwise but overall that's fine
And these days those in Econ study real analysis too
(worth mentioning that i.e. g_n(x) >= 0!)
oh interesting
Can’t x takes 0?
Since n is natural number x can take 0
depends on the convention
for set theory it can sometimes be helpful to think of 0 as a natural number
Usually I will exclude n=0
a lot of times i think in like i.e. the US 0 is not natural
since on rudins if we take 0 then it can have many problem
anyway here it doesn't make sense if n=0, cus then we have 1/0 so they just mean n >= 1
Yes but here I really excluding 0 as a natural number
also i'm curious by how u've differentiated x^n/n lmao, chain rule with the exponential???
i mean it works but like power rule lol?
Generalized power rule I learned from course cal 2
You aren’t gonna to leave some short comments for enlightenment
oh right if u haven't done it in analysis makes sense
Cal 2 includes generalized power rule
so you compute g_n'(x) = x^(n-1)
Yes
what does this converge to pointwise?
Yes you’re right it doesn’t converge uniformly
LY will enlighten u
It goes to 1 whenever x=1 otherwise 0
I made a careless mistake
What’s the point of that epsilon - argument 
That looks quite daunting already 😭😭
It converges uniformly on [0,1) eight
no unfortunately
Is the rest correct I only need to delete the epsilon argument right?
Why?
yeah so if we use the half open interval [0, 1), it doesn't converge uniformly because intuitively, no matter how big n is
Forgot the neighborhood again not studying math makes me this dumb😭
x^n will be very close to 1 for x very close to 1
even though the limit should be 0
hence convergence is not uniform
So if I fix it by saying it converges uniform on [0,1-delta] it should be correct right?
Is the part a s proof correct? I actually used Dini theorem though
the part a proof is fine
it's a bit hard to judge ur proof cus it depends on what analysis results u already know
but i think it's fine to say x^n -> 0 as n -> infinity for |x| < 1
Bcs I ain’t really math student so just assume as little as possible
you are still a pro
Is that fine though? Shouldn’t I use m test, definition or dini theorem
I am not
Is the convergence uniform on [0,1-delta]?
i mean if ur doing uniform vs pointwise convergence then i think ur beyond the point where you need to rigorously justify that i.e. 1/2^n -> 0
And is the format or the way the epsilon argument is crafted fine?
You’re right!
The inequality is so hard
i mean i mentioned my thoughts about ur formatting
if u want i can write out what i think would be a nice way to present ur work?
say yes ema
Please do it for me owwwww 🥰 you’re so nice!!!!
And again. Is dili Theorem valid for part 1 though?
i wasn't aware of dini's theorem but it looks like it's fine
Is dini s theorem correct for part a? You’re like a pro right you solved that daunting integral
havent bothered looking yet
oh wait ur thing for showing g_n(x) is decreasing is kinda cursed lol
n is meant to take values in the natural numbers so differentiating it is a little bit cursed
but you can phrase it differently to make it less cursed
was about to say that
You’re right I should use inequality directly
instead of the derivative you can just show g_n > g_(n+1) or g_n < g_(n+1)
Then I qualify dini theorem
Or I use Bolzano weierstrass theorem which is easier right?
I will try to refine it a bit and be right be right back
oh wait ok so ur thing is correct, but it's ur method is a little bit overkill
Please show me it I really wanna see 🥰🥰
it's like quite easy to show directly that g_n -> 0 uniformly
i'm writing it up now
I have a Lemma from my notes from last semester that says a function sequence f_n converges uniformly to f if and only if ||f_n - f||_oo -> 0 as n -> oo.
|| f ||_oo = sup|f(x)| denotes the supreme norm on D
I revised mine till
dini's theorem requires ur limit function to be cts
so you should find the limit function as g(x) = 0 first then apply dini
continuous
you need to put a little more justification why
"2 limits" => not uniform continuity
yh
That characteristic function h is so clever I love it 🥰🥰🥰🥰
Did you use sequential test too
I shall refine it again
Thanks so much you’re brilliant 🥰🥰
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The base-$10$ integers $36$, $64$, and $81$ can be converted into other bases so that their values are represented by the same digits $\triangle\Box\Box$, where $\triangle$ and $\Box$ are two distinct digits from $0$-$9$. What is the value of $\triangle\Box\Box$?
938c2cc0dcc05f2b68c4287040cfcf71
@tough mica Has your question been resolved?
Triangle and box are 2 and 3?
Ok
36 in base 6 is 6^2 + 0 + 0 = 100
100 in base 10 is 10^2 + 0 + 0 = 100
81 in base 9 = 9^2 + 0 + 0 = 9^2
Idk
81 in base 9 is 100
100 typo
so triangke square square is ?
100
Idk, 100
yes
Why is that
Because they are perfect squares
yes
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The figure below represents the floor plan of an office. The owner of the room intends to install a granite strip to decorate the floor. This strip is the non-dotted part in the figure. Knowing that rectangles ABCD and EFGH are congruent, indicate how many meters of strip will be needed:
(consider sqrt(2) = 1,4
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@true lake Has your question been resolved?
😭🙏vro
@true lake Has your question been resolved?
@true lake Has your question been resolved?
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$\int_0^{+\infty} \sin(x^2) dx$
Task Bot
How to compute this ?
the standard way is by complex analysis, if you're familiar
for a real approach you might want to look at https://math.stackexchange.com/questions/187729/evaluating-int-0-infty-sin-x2-dx-with-real-methods/190293#190293 for some methods
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Hi for part b i dont get why the solutions absolute value the integral
and why they only consider the bounds from 0 to 1
this is what i started doing
what your doing makes more sense to me too
and i think it should be a + instead of a - between the two integrals
oh oops ur right
The absolute value is probably meant to be inside the integral rather than outside. then it would be the same as your working
were they meant to put a 2 in front of the entire thing? Cus its symmetrical?
This is the enclosed region. Because the enclosed regions swap, if you did the integral f(x) - g(x)), it would likely zero out.
oh do you mean what i did in my working?
You asked why the absolute value signs are there.
ohh
If you subtract f(x) - g(x), you get this new equation.
As you can see, part of the bounded interval is negative.
Ah I understand, if you absolute value f(x)-g(x) then it gives you the entire area between 0 and 1
Yes. That's not the usual way of doing this though. One would typically create two separate integrals on two different intervals and subtract the appropriate function from the other.
So basically what I did?
wouldn't this force him to separate them either way, if he does not have a calculator to evaluate the integral
wait what
Almost, you would add the two integrals instead of subtracting them.
ye thats my mistake
alright thanks guys
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ok idk where i went wrong but i got a negative area
The initial integrals are correct. You mathed wrong somewhere. I get 1/16.
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I need someone to help me understand this. I am confused as to how to divide this or even if I can factorize it.
dividing polynomials
you should probably watch a video on how to do it if you dont know how
i do know how to do that
what specifically about this one are u unsure about
i divide 12x^5 with 3x^3 right?
i am kind of confused about there being 3 digits, things, wathever they are called in the second polynomial
wym 3 digits
what do you multiply 3x^2 by to get 12x^5
4x^3?
yea
so thats ur quotient so far
than u multiply the denom by 4x^3 and subtract it ffrom the original to get a smaller dividend
than u just go down the line
like this?
well u would multiply 4x^3 by 3x^2-x+2
than subtract that new thing from the orignal
of 12x^5
so it cancels
so now i just subtract all of those above?
wym all of those above
this is really just long division with variables exact same process
so like this?
it would be 3x^4 - 4x^3 -x -2 wouldnt it
yeah but i dont write those, but ig i should
so i repeat the same process? divide the 3X^4 with the 3X^2 and then multiply with the brackets?
wouldnt it be negative 3x^3
oh yeah you are right, mb
now i just have to correct it
if you need anymore help with this feel free to ping me
okay, i will ping you when i finish this
👍
ye -1 right to the equal sign
tyyy
i do have a few more problems, not long, just practicing for an exam tomorrow, if it is not a problem
do i use just factorize it here?
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@bleak cargo Has your question been resolved?
<@&286206848099549185>
like this?
yup
@bleak cargo Has your question been resolved?
yeah no try again
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cant follow how this happend or what -1/3 means
So, the steps are, move 1 over so it's 4x^3=1
Then x^3 =1/4
Now to get the x we raise the expression with ^(1/3)
So we have x = (1/4)^(1/3)
Now this doesn't really look nice
So we use the rule n/x = x^(-n)
Which showes x = 4 ^(-1/3)
This helps @vagrant acorn ?
No problems :)
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Am I allowed to do this?
should be ok
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If I prove that the series of |an| is divergent, then does that also mean that the series of an will be divergent?
Hm. Interesting
(-1)^n*1/n
|an| diverges using the p series test
But an converges
Using the liebniz test
Thank you.
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What is f(x)?
oh mb
so since the thingy is in the middle
we reflect the left side of the y axis innit?
and vvertical stretch by 2
but the mark scheme says otherwise
I'm not sure what is meant by "find the coordinates of"
Are they asking for where (x, f(x)) gets mapped to in the form of (x, f(|2x|)) or are they asking about (f(x), f(|2x|)) or something else? I'm not actually sure.
What does the mark schema say?
yea i think
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yep
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this is what i did and i continued it but got the wrong answer
i put it in an integral calc, and the answer i got there was different to the answer given to me
i think theres something fundamentally wrong with how i set up my equation
@meager gale Has your question been resolved?
What did they get, and what did you get? 
i found the mistake dw
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Is this correct?
yes, but you can simplify that further to just arcsin(x/a) + C
if a > 0, a / |a| is just 1, so that case is the same
and if a < 0, a / |a| is -1, arcsin is odd so the negatives cancel
erm did i mess up
Even though arcsin is odd, you don't get a negative sign introduced by that, do you 
At best you'd get e.g. arcsin(x/(-a)) or something, unless I'm fried 
yeah this is what i was trying to go for lol
i guess it's technically best to leave it like this then
ah right if you graph an example of this with negative a, just arcsin(x/a) doesn't make sense. i suppose the reason arcsin(x/a) is always on integration cheat sheets is that they assume WLOG that a > 0 since (-a)^2 = a^2
well you can take a/|a| = sgn(a) (we are assuming a is nonzero anyway). then inside the arcsin we can write 1/a = sgn(a)/|a|, and the sgn comes out (odd function) and cancels with itself. so a more convenient (but equivalent) form would be arcsin(x/|a|) + C
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If $(x_n) \to x$ show that $\sqrt{x_n} \to \sqrt{x}$.
\
As $(x_n)$ converges, it follows that $\forall \varepsilon >0. \exists N>0,$ st $n> N \implies \abs{x_n-x} < \varepsilon^2$
\
We wish to show that this implies $\abs{\sqrt{x_n} - \sqrt{x}}< \varepsilon$.
\
We also find that $(\sqrt{x_n}+ \sqrt{x})(\sqrt{x_n} -\sqrt{x}) < \varepsilon^2$
now what
ƒ( wai ina teacup)= I don't know
@keen pawn Has your question been resolved?
<@&286206848099549185>
Use the max of the two values
I also considered using boundedness
yeah, I did think of that, but that requires more than we have at our disposal , no?
Hmmm true, I guess you can't just use the max of the two values.
ƒ( wai ina teacup)= I don't know
x=0 is done
did you do that elsewhere
yes
okay then you should capitalise on the fact that x > 0
sqrt(x) + sqrt(x_n) >= sqrt(x) > 0
you get to choose what |x_n - x| is less than
lets say $\abs {x_n - x} < \eta$
[ \abs {\sqrt {x_n} - \sqrt x} \abs {\sqrt {x_n} + \sqrt x} < \eta \
\abs {\sqrt {x_n} - \sqrt x} < \f \eta {\sqrt {x_n} + \sqrt x} \le \f \eta {\sqrt x}
]
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@tough mica Has your question been resolved?
@tough mica Has your question been resolved?
@tough mica Has your question been resolved?
maybe translate that to english first and it will be easier for ur question to be answered
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im to find a, but if i expand this, wount i be left with ln(-1)?
integral of 1/x is ln|x| not ln(x)
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try finding the limit with respect to a, then solve the relatively simple resulting equation
w.r.t 'a'...
can you explain a bit more
what have you tried si far
solve the limit while leaving a as a constant
i assume you're familiar with this form since you're solving this problem too
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for x = a, a - 2 in Dom(f):
f(x) at x = a evalutes to f(a)
and for f(x + 2) to evaluate to f(a), we must have x = a - 2
Thus, we can see that f(x + 2) is a translation of f(x) 2 units to the left
would an argument like this work?
@fierce edge Has your question been resolved?
hmm what?
What was ur doubt exactly, can u tell it again
Ig u were asking can I write it as some shift in the graph. Along x axis right?
@fierce edge .
I know it is a shift
I want to know if my argument is correct
It might be but like do i really need to specify x = a-2 in Dom(f) too?
a - 2 might not be in Dom(f)
but it's in Dom(g) where g(x) = f(x+2) as long as a is in Dom(f)
your argument is fine, and i would have said something similar. one might make explicit that this is literally the definition of what it means to "shift the graph left by 2", that is, (x,y) \in graph(g) if and only if (x +2, y) \in graph(f)
but that's exactly what you showed anyways
oh
i don't remember the solution but i recall them only mentioning a in Dom(f)
and nothing about a - 2 in the context of "domain"
but yeah okay we would have to say x = a- 2 is in the domain of g(x) right?
if we reason this way
yes but that's okay, because a - 2 + 2 = a ;)
mhm you get f(a) so you only need x = a to be in Dom(f)
yeah
but that's good because we already assumed that a was in Dom(f)
because (a,f(a)) was in graph(f)
this makes sense, but like idk somewhere in the solution they only just talked about a and nothing else (no g(x) having x = a - 2 in the Dom or whatever)
maybe i'm misremembering
yeah, you should not trust solutions given in a solution manual as much as your intuition (hot take)
😭 oh
but like
I like looking at solution manuals cuz like the author is clearly better than me at this
but i guess my idea works as you affirmed
so meh

hi
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what could be the example of one to one function that isnt strictly monotonic
your example is correct i think
If it’s not continuous then take any piece wise function
I think f: R \ {0} -> R given by f(x) = 1/x would work, yeah?
it's injective, but not strictly monotonic
yes that seems to be correct
isn't that strictly decreasing?
Not when it’s negative
it is monotonic in R+ and R- but not in the whole domain
i dont htink you can say that its decreasing on its whole domain
thus it isnt strictly monotonic? iguess
f(x) = sin(x)
exactly
🙂 it does both
but it is not injective
its not injective
oh yeah
I thought that f' just have to have the same sign
alright thanks fot help
that is right in case the domain was continous
aka an interval
ah I see
bc then the slope across some interval is just the sum of all the f'
divided by the interval length
I mean like
$\frac{f(b) - f(a)}{b-a} = \frac{1}{b-a}\int_a^bf'(x)dx$
Sepdron
yes that an elegant way to see it
so the domain doesn't have to be continuous right?
just that condition has to be true
if you allow, piecewise functions, then
$$f(x)=2\lfloor x\rfloor-x$$
is a really nice example of this
artemetra
i don't think you'll find a continuous example though, because by IVT you'll be able to find points that would break injectivity
I think it is mandatory to have a continuous domain to use that result using derivatives.
or you'll have to work with really strange domains ig
but on an interval no, there is no such continuous function
@oak galleon Has your question been resolved?
I moved to #help-4 so I don't take over this channel
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i need help ik volume and stuff but idk how to start
@calm pewter Has your question been resolved?
First you need to calculate the volume of the juice given the position its already in at the start
Do you know how to do this?
so 20x6x10?
like this?
That would be the volume of the carton itself
yh
Remember the juice doesn’t actually fill the entire carton
we want the volume of the juice so you must account for the given depth
so 10x20x8?
the box lies plain?
The box originally lies on the 6x10 face
the height is the 20, we want to change that height for volume of the juice
waht do they mean by depth?
Im not sure if they mean 20-8 or 8+0
Depth is usually measured top down
So I would assume it’s 12
amrk?
Well whatever, if we assume its 6x10x8 then its going to be 480
Does this make sense so far
no
480 cm^2
Which part is confusing you?
Because the original orientation of the box is on the 6x10 face
The diagram shows this
is depth the height?
Yes, I think so
Yes, but it depends on how they are measuring depth which they aren’t very clear on
yh
It could be 20-8 (depth from the top of the carton) or 0+8 depth of the fluid itself
I would say just pick one and then if you’re wrong you’re justified to complain
yh isee
I’d guess 8
les stick to this
Sure
yh
So its 480
whats the next step?
Right, so when we turn the carton on its side, we expect the volume of juice to stay the same right? Just reorient itself with gravity?
yh
Okay so we know the volume of juice when its in the original orientation must equal the volume of juice in the rotated orientation, this lets us setup an equation
how we set it up
Recall that the original base of the carton (the bottom in the original orientation) is 6x10
yh ty
does this make sense?
yh
Alright, good. Any other questions?
Yup!
Sure, what is it?
u know for this i have solved the inequality i got t is less then 5.5
the answer sheet says
the largest value is 5
i wrote 5.4
why is not 5.4
Because is says t is a whole number
5.4 is not a whole number
5.5 for A
it always the things like this tht get me in the exam
5 for B
yh
Yeah they get tricky
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Hello I have a logics question, it goes as follows:
Only Squares can have two or more Squares on their right side.
I constructed this sentance:
∀x: (∃a: (RightOf(a, x) ∧ Square(a) ∧ ∀b: (RightOf(b, x) ∧ Square(b) ∧ (a ≠ b))) ⇒ Square(x))
But it seems to be wrong for some reason?
I don't really see why and where
I started with abstracting it a bit
So considering only Squares can have this characteristic of having "two squares or more to the right", it has to be a subset of all squares
Mephisto
Mephisto
and
Mephisto
This would be always false
Mephisto
this one looks fine
This part says that if R(b), then a is different from b
yeah so if b is a square and is to the right of x (our original premise) it has to be a distinct square from a
which could be translated as not R(a)
thats not what we want
that would imply that a itself is not a square
The formula does it for one square only I believe, and maybe because your quantifiers are all over the place
say that R(a) means "a is good"
then this translates to
"all good things are distinct from a"
therefore a can't be good thing
which is obviously not what we want
so it's a contradiction giving an empty set?
yeah, its a contradiction together with saying that R(a)
hm I see
Anyway we want 2 things:
- existence of some a with R(a)
- existence of some b with R(b) and b != a
This captures it well
I tried:
∀x: (∃a: (RightOf(a, x) ∧ Square(a) ∧ ∃b: (RightOf(b, x) ∧ Square(b) ∧ (a ≠ b))) ⇒ Square(x))
but it's still wrong :/
i need to count the parens, gimme a moment
We have access to LogicPalet through our university
when I run this sentance it generates this world as a counter example and proof that the statement is false
can you show me the proof?
idk if I it can generate a whole proof, it just generates an image for which the given statement still holds
oh, well
as a counter example
but it seems so confusing because how can there be triangle there if it's an implication
it's like the premise is correct, but the conclusion is false
hm maybe it's because I used an existential quantor for a and b?
Negation of this would be existence of object which satisfies the premise but isnt a square
RightOf(x,y) means x is to the right of y
hm I can just say not (Triangle(x) or Pentagon(x))
Would RightOf(x, x) be true
in the conclusion
ooh good question
Its the only thing that could fail here
ah okay in the description they say it's a non reflexive relation
Hmm weird
so I assume RightOf(x,x) would be false
hold on I'll try to generate a proof
I think it might be possible
Okay got it
Just had to name all elements
woops can't use a and b
x too...
🤦♂️
Wait can it name the objects here as well
Why do you have triangle there
Verifying this please
yeah I copy pasted it from my application
ah I was executing the wrong one, my bad, I was testing something
here's the new proof
okay so
c and d are triangles
meaning Square(c) and Square(d) must be false
but the statement as a whole is true
so the premise must also be false
which should not be the case for c
It says its true? So it does workm
nono, the statement as a whole is true, i.e. there are no contradictions in it
but it still doesn't generate a world where our original premise holds
"only squares can have two or more squares to the right of them"
Yeah, and we modeled exactly this statement
And it works just fine
It's true in this world
no, because a triangle has two squares to the right of it
Oh
which is true in our model
that's the issue
we get
∃a: (RightOf(a, c) ∧ Square(a) ∧ ∃b: (RightOf(b, c) ∧ Square(b) ∧ (a ≠ b))) ⇒ Square(c)
which is true. Why?
with c a triangle
considering the whole is true
Can you expand x=c?
and Square(c) is false
∃a: (RightOf(a, c) ∧ Square(a) ∧ ∃b: (RightOf(b, c) ∧ Square(b) ∧ (a ≠ b))) must also be false
yeah
I think it's a problem with the right of statement indeed...
considering RightOf(c,c) returns true
ohhh no wait
it returns true because both the premise and conclusion are false
essentially.... it's like our truth values are wrongly modelled
so putting a triangle on our premise side, should return true
meanig we should use implications again
oh wait
got something?
sorry, my dad called me so i was gone for a while
ah no worries
anyway, it seems like it interprets
∃a P -> Q
as ∃a (P -> Q)
if im not mistaken
and therefore an easy fix would be adding parens
not sure if I understand what you mean
fixed
i was just too lazy to find the ∃ symbol
∀x: ( ( ∃a: (RightOf(a, x) ∧ Square(a) ∧ ∃b: (RightOf(b, x) ∧ Square(b) ∧ (a ≠ b))) ) ⇒ Square(x))
added new parens
did it work?
it had to be a conjunction
yeah... it does
conventionally, ∃a P -> Q would be interpreted as (∃a P) -> Q not as ∃a (P -> Q)
yep
it's a different statemetn
what surprises me is that the software interpreted it like that
against the convention
the convention is that quantifiers have higher precedence
but the software decided to ignore it for some reason
yeah
I mean
I always use parenthesis after a quantifier
maybe they were just misplaced?
∀x: (∃a: (RightOf(a, x) ∧ Square(a) ∧ ∃b: (RightOf(b, x) ∧ Square(b) ∧ (a ≠ b))) ⇒ Square(x))
This is just
∃a: (P(x)) ⇒ Square(x)
it's correct and me and any sane person would interpret it as (∃a: (P(x))) ⇒ Square(x)
but LogicPalet decided to be illogical and interpret it as ∃a: (P(x) ⇒ Square(x))
I must say I was very confused
same
I always use sets to make sense of questions like these
so it's almost impossible to make errors
and my sketches were perfect
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thank you
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Hi
@pulsar frost Has your question been resolved?
Nope
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Thankyou
Wdym?
you have that AB is shared between those two triangles
notice that angle CAB = angle CBA
thus angle DAB = angle EBA
you have side and angle, so you need to either find another shared angle or side
what have you tried?
Hold on a minute
Forgive my handwriting but is this going in the right direction
@crisp stratus please speak something
@pulsar frost Has your question been resolved?
.close
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What is the answer to this question?
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.
<@&286206848099549185>
don't ping helpers several times
sorry i am new here
i can try
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.reopen
✅
nevermind it isn't always positive
but i think if it is then you can get the maximum
or actually nah
idk :(
.close
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ths for trying tho
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Sin ^12?
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Calculate $\frac{\partial f}{\partial x_k}, k = 1,2,3$ for the functions $(x=(x_1,x_2,x_3)) \ a) f(x) = \ln|x_1x_2+x_2x_3+x_3x_1|$
Merineth 🇸🇪
I'm not sure i understand this correctly
I want to find the partial derivative for first x_1 ?
yes, you first want to find the partial derivative wrt x_1
$\frac{\partial f}{\partial x_1} = \frac{x_2+x_3}{x_1x_2+x_2x_3+x_3x_1}$
Merineth 🇸🇪
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