#help-0
1 messages · Page 9 of 1
the info page says ProductLog[k, z] for principal value k = 0
Thanks ill try
This gives us the upper half of the curve
Maybe there was something in my algebra that missed the other half of the solutions
Lol
nice job though!!
By swapping x and y we get the lower part
So all we need to do now is minimize the distance to the origin
,w plot (1+(1/e^(ProductLog[-1,-ln(x)/x)]^2)
Lol wolfram really don't like doing calculus on W
Ignoring portion of domain over which it is not a real function:
The minimum is clearly at x=e
@tame willow you can work out the calculus yourself now probably!!
If you know the derivative of W_-1
Or you can derive it implicitly
,w d/dx ProductLog[-1,x]
@molten pivot i'm blanking on why the origin minimization is 1 + y^2
Yeah I was wrong on that actually, thinking of arc length formula haha
You would have to minimize x^2+y^2 to minimize d^2 (squared distance)
It's generally easier to work with squared distances than actual distances, so we can just minimize d^2 instead of d because squaring preserves order over the positive numbers
oh lol! yeah it works out for d^2 still
pretty rad to basically work it out on a napkin
@tame willow Has your question been resolved?
What has not been answered?
I mean it looks like there's nothing really left to solve
have you considered reading #❓how-to-get-help
Sorry I forgot.
.close
Closed by @tame willow
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
completely lost on this one..
some wild optimization prob?
are they ending up eight yards apart along the perimeter? i'm thinking that must be the case or i think this will get out of hand really fast nvm
@fierce prairie Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
I am having trouble trying to prove by induction that (1 + x)^n ≥ 1 + nx. I end up trying to show that (1 +k+1)^j+1 ≥ 1 +(j+1)(k+1) and I have no idea what to do from there
I'm not sure. I know x is a real number and they are both greater than or equal to 1
So if x is a real number, how can we use induction on it?
What I'm getting at here is that we only need to use induction on one variable
oh gotcha.
The variable that takes integer values
Base case: n=1 x=1 (1+1)^1 ≥ 1 + 1*1
2 ≥ 2 therefore, n=4 x=4 is true for (1 + x)n ≥ 1 + nx
Suppose n=j x=k such that j ≥ 1 and k ≥ −1
So why are you substituting for x at all?
of so I leave x and just use induction on n?
Yeah, exactly.
Induction works on some statement P(n) that depends on n
In this case the statement is for n=1 : (1+x)>=1+x which is true for all real x
We then assume for n=k (1+x)^k>=1+kx for all x
Base case: n=1 (1+x)^1 ≥ 1 + x
1+x ≥ 1+x therefore, n=1 is true for (1 + x)n ≥ 1 + nx
Suppose n=k such that k ≥ 1 and x ≥ −1
We will show that (1 +x)^k+1 ≥ 1 +(k+1)x
Yeah, not all real x actually, you are right
The range on x you give is correct
But the point is that that is part of the statement we assume
I guess I am just confused on knowing when an inductive proof is done because it does not feel like it has really proved anything
Do you mean you are confused when you need to use an inductive proof
Or are you not sure why you need an inductive proof at all
no just how in this case to simplify the problem in such a way that it is evident the left side is greater than or equal to the right
The point is that the assumption we make is a piece of information we can use
So in what you wrote above
We start with the left hand side of the k+1 case
And we manipulate it using that piece of information we have to get the desired right hand side
So in other words, the k case implies the k+1 case
The k case enables us to obtain the k+1 case
Is there a way to show it using binom?
Ah i see
Social Capital Gainer
I think that is what has me stumped because the only way I can think of to get rid of the exponent is to go to that root and that would not be helpful
Ok another way to do this
Is to start by writing the statement we have assumed to be true
,,(1+x)^k\geq 1+kx
Social Capital Gainer
How can you generate this here
What can we do to the k case to get that (1+x)^(k+1) piece somehow
How can we get that +1 in the power
I'm really not sure
What do i multiply 4^6 by to get 4^7?
so I multiply by k?
so it can just be simplified to (1+x)>= (1+x)?
Not really
What I am getting at is
We can multiply both sides of this inequality by (1+x)
Since (1+x) is positive, then the >= sign doesn't change and we get
,,(1+x)^k(1+x) \geq (1+kx)(1+x)
Social Capital Gainer
What does the left hand side become?
(1+x)^2k
(1+2x+x^2)^k?
Social Capital Gainer
no idea
So you agree that 4^3, for example, is 4×4×4
yes
So what is 4×4^3
4^4
Yeah
So what is this
so (1+x)^k+1
Social Capital Gainer
Social Capital Gainer
Do you agree?
yes
Nice
So the left hand side is what we want
Now we need to manipulate the right hand side
What do you think we can do?
Social Capital Gainer
What algebraic manipulation can we do to that
What can we do with a pair of brackets like this
I'm not sure because you cant say (1+kx)^2 because they are not the same thing. You could divide the (1+x) from both sides
We we put it in deliberately, we wouldn't want to divide it off again
If I gave you something like
(x+3)(x+5)
What could you do to that
Really simple thing
To do
well you could just multiply
So lets do that here
1+x+kx+kx^2
1+x+k(x+x^2)
Here you factored k out, we want to factor x out
Instead of k
1+x(1+k+kx)
Yes, that is correct, but we want to leave kx^2 alone, you will see why in a second
so 1+x(1+k)+kx^2
Social Capital Gainer
This is almost what we want
The k+1 case
Except we have an extra piece, the kx^2
What can we do about that?
no idea
Social Capital Gainer
Social Capital Gainer
yes
Social Capital Gainer
alright
Social Capital Gainer
To get rid of that kx^2
no idea
Ok
So kx^2>=0
Yes?
kx^2 is either positive or 0
Since k is positive
And x^2 is always positive (or 0 when x=0)
yes
Ok
So on the right hand side, we have added a number which is either making the right hand side bigger than it would have been without it or leaves it unchanged
So if we just drop that term
,,(1+x)^{k+1} \geq 1+(k+1)x
Social Capital Gainer
Then the right hand side is either unchaged or is smaller
This is because
,, 1+(k+1)x+kx^2 \geq 1+(k+1)x
Social Capital Gainer
So we went to a smaller (or equal) number
Therefore, this is true
,,(1+x)^{k+1} \geq 1+(k+1)x
Social Capital Gainer
Does that make sense?
yes
So that's it, we obtained the k+1 case out of the k case
We have proved it by induction
ok thank you
so we inherently know that the left side is greater or equal to the right side now?
Yes
We assumed that it is true for k
And that assumption means that it must also be true for k+1
As we have just shown
Since it is true for 1 then it is true for 2, since it is true for 2, then it is true for 3 and so on
Closed by @upbeat gazelle
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
in response to #help-4 message
@fallen verge I had to go, but I don't quite understand what you did here
why is it 2p + 8 = 90?
They both walk almost around the rectangle
P is the perimeter
oh lol
The 8 probably means as the crow flies then
@fierce prairie Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
would someone be able to help me with this please
i think we get the expected value of X hat but i'm confused on how we get the value for that
and it should be equal to usual estimator?
im a bit confused i'll see what i can do
hint to get started: $E\left[\frac{3X_1 + X_2 + \cdots + X_{n-2}}{n}\right]= \frac{1}{n}(E[3X_1 + X_2 + \cdots + X_{n-2}]) = \frac{1}{n}(3E[X_1] + \cdots ???)$
Bungo
oh alright that's great i'll work with that then
thank u
sorry so now i'm a bit lost
i've rewritten it as that
i think i'm meant to be working towards proving that what we had here is equal to
sry trying to understand this but i think we're trying to prove that E(X~)=X-
so if i have this, i'd try to prove that
-E(X_(n-1))-E(X_n)+2E(X1)=0?
sorry for the ping @naive valley but would this be correct? how do i go about proving this
@safe mural Has your question been resolved?
@safe mural Has your question been resolved?
@safe mural Has your question been resolved?
yes, the work in your screenshot is right
(sorry, was signed out for a while)
now just use the fact that all of the X_i's have the same expected value (because they are i.i.d.)
ah alrighty thank you so much
ah one small correction, $\overline{X}$ is $\frac{1}{n}(X_1 + X_2 +\cdots + X_n)$, not $X_1 + X_2 +\cdots + X_n$, so your third line is not quite right
Bungo
i think E(X-) is just nX- so it should be n(all of that) right
which is just (all of that)
or is that unnecessary?
on your third line, if you replace $E(\overline{X})$ with $nE(\overline{X})$ it should be correct
Bungo
Closed by @safe mural
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
|a-b|<|b|/2 implies |a| > |b|/2
how do i prove this
Closed by @tough pond
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
hi
how can i do apply combine like terms
you combine shit that can be combined
(fg)(x) = (3x-2)(x²+2x-3)
= 3x(x²+2x-3) -2(x²+2x-3)
= 3x³+6x²-9x-2x²-4x+6
= 3x³+4x²-13x+6
how can i use combine like terms on this ex.
you already did
You done combined them
the second to last step
like explain how to do combine like terms
ik its already combined but can you explain it
wait lol let me review it
Closed by @foggy onyx
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
$\log(a^b) = b\log(a)$
riemann
do you know?
summation of 2n terms
@tidal zealot Has your question been resolved?
bruh thats wht i did
but idk what happenes to the two
2n is your final term
so is the answer B
no
why 2n
Closed by @tidal zealot
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
how is the range of this function from (0, infinity)
@tidal zealot Has your question been resolved?
Where do you want help with?
The property used here is this
@tidal zealot Has your question been resolved?
how did they know c =2
Well you can take c= anything it doesn’t matter as it’ll cancel out in next line
@tidal zealot Has your question been resolved?
Closed by @tidal zealot
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Heyo . was just wondering how you calculate the rotation of a matrix
wdym
This has realy confused me cos i thought you would just match a term to get theta like sin theta = -1/Sqrt(2) and you would get Theta as the anticlockwise rotation of the matrix but..(show notes)
Yeah thats what you do
then its clockwise ???
the fact i got two didnt put me off as much as when i subed them back in in any form i didnt get the matrix ???
or i should say the value in that element of the matrix?
iv'e got the answears and they say it is 225
judging by the notes your using the edexcel fm book?
yeah!
right, theres a clockwise rotation matrix
which just changes the sign of the sin theta
it should be in the formula booklet aswell
so i should use the clock wise theta to get the origonal matrix values
ok lets say sin(theta)=1/root2
Or just
Plot them, then see when they both have the same value for theta at -1/root(2)
,rotate
So it's an anticlockwise rotation 225 degrees, or a clockwise rotation of (360 - 225) = 135 degrees
right but its much simpler to use the clockwise rotation matrix
becuz u can see its 135 degrees clockwise
ohhh yeah
Ig? I find it easier to find an intutive solution rather than have to remember another equation
Can do either tho
and matrix questions in exams are much harder than textbook questions
sure , so i can see the answer is 225 . but if i sub that into cos or sin i dont get the og matrix values
True, chapter 6 was pretty easy
135*
Yeah, if you plug 135 into the clockwise matrix, it will give you the original
Thats the anticlockwise matrix
yh it does
cos 135 is - root 2 / 2 . isnt it?
omg yeah
sos didn't see that
dammm thx!
that taken me like an hour
welp , thank you ever so much ! @keen socket @uncut torrent
maybe use formula booklet **
Nw, good luck with further :)
thx lol, gonna be my entire summer. spose you've done it ?
Just finished first year
same
Oh damn
i d say Core pure 2, further stats, further mechanics, core pure 1
i fucked up core pure 1
Yeah 💀 that tennis question
tennis?
edexcel
Yeah same
u mean paper 2 vector question?
Only did one pure paper
right maybe different spec
what modules would u recommend? i wanna do mechanics and pure or decision
I cant speak for decision, but I didn't find stats too hard.
dont choose mechanics u ll regret
😭
even if u do physics
lmao rly
Its fun but yeah its evil
cuz mechanics collision is different pain
Ong
mechanics in general was pain
I only started getting full marks on those questions towards the end of the year
dont be fooled by the spec, since it says kinetic energy and stuff
its only really 1 topic thats hard
but in the recent exam they put like 3 of them questions in it
and they happen to be the 11 markers or 12 markers
Pain
yeah
i keep putting this clip in my notes
BBC Newsnight's political editor, Nicholas Watt, says a cabinet minister responded with 'fuck knows' when asked why Theresa May is holding another Brexit vote that she is expected to lose. The minister reportedly went on to say, 'I'm past caring, it's like the living dead in here'
Subscribe to Guardian News on YouTube ► http://bit.ly/guardianwi...
.close
Closed by @spare crow
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Hold on
Does this make sense
I was a bit confused on how to do the Y1,...,Yk parts
you can just prove it using induction
it would be much easier
you just have to prove the case Au(BnC) = AuB n AuC and the rest is trivial
@flat saddle Has your question been resolved?
I have done that in a previous question
okay so you can prove the general case with induction
oh if you didnt learn it then no let it go
I just want to know if my proof makes sense
@flat saddle Has your question been resolved?
.close
Closed by @flat saddle
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Remember:
• Ask your math question in a clear, concise manner.
you have an exam going on right now?
and you want to cheat on it using this server?
that's against the rules
We can't help
Nice try
.
Don't help someone cheat
joking about committing bannable offenses is frowned upon.
I'm not
They're literally doing an exam rn
ok that just looks like an insult at this point
That means you don't even need help and you're just wasting everyone's time, which is against the rules too
<@&268886789983436800>
.close
Closed by @lilac nest
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
<@&268886789983436800> before this channel closes for good: OP ( @static raft ) is a spammer and self-admitted exam cheater
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
I need help with part c)
Would this be P(1-t,-3) ?
Because answer says P(1+t,-3)
Closed by @cunning trout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Hello! I am looking at inverse trigonometric derivatives at the moment and am struggling with a concept. I am aware that the derivative of arcsin x is 1/sqrt(1-x^2) and this is achieved as cos(y)=1-sin^2(y) hence 1-x^2. however 1-x^2 and 1-sin^2(y) are not the same thing so why is it allowed? sec(y) is not equal to 1/sqrt(1-x^2) when plotted. Can someone explain?
how'd u get this
this is achieved as cos(y)=1-sin^2(y)
can u show ur derivation for sin inverse x
sorry i meant cos y = sqrt(1-sin^2(y))
y=arcsin x therefore x=sin y, dx/dy = cos y. [ cos^2(y)=1-sin^2(y) =1-x^2] therefore dx/dy=sqrt(1-x^2) therefore dy/dx = 1/sqrt(1-x^2)
but this implies that 1/cos(y) = 1/sqrt(1-x^2) but thats not true when plotted
why isnt that true
u assumed y=sin inverse x
oh a sec
so its just the fact that we made the variable x = sin y and so under that condition the derivative works?
cos^2(y)=1-x^2, ( we know x=siny ), how is this expression wrong
well i guess its just i plotted sec y and 1/sqrt(1-x^2) and they didnt equate thats all
perhaps i did something wrong
yes, maybe
@flat walrus Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Guys, can anyone help me prove why 0^0 = 0?
well you can't prove it because it's not true
limits of the form 0^0 are indeterminate
often it is convenient to define 0^0=1
Oh, desmos wrong?
did you plug in 0^0 into desmos?
it tells me it's equal to 1
So how do I prove 0^0 = 1? @mortal trellis
Can't you still use limits to prove?
no, limits of the form 0^0 are indeterminate
Not sure how but
they can be anything
it's undefined unless we are in a context where it's convenient to define it as equal to 1
Closed by @native cloud
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
yeah
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
is there any way to take a random number and figure out either what polygon(s) it is from or the value of n to where it is contained, or if its just a polygonal number?
without looping / testing every number
for say a large number like 32098402374, is it possible to find either the value of n or what polygon sequences it is in?
basically i need to tell if a large number is figurate really quickly
<@&286206848099549185> is this in any way possible to do?
You have the first step
Multiply it by 2
To get rid of the one half
Have u heard of a ticker function
no i have not
Why don't u just use recursion for this?
im not sure what that is
right now im just checking it against every polygonal number
there are infinite types of polygons as well as an infinite number of polygon numbers
So u can. Only determine the polygon when n is 1 from first glance
theres got to be some way to backtrack a number, or at least make it smaller while keeping it in the same row/column?
im having a script do the work, but when its working with big numbers looping through this many times it would take years to get the answer
Every one of these can be written as a triangular number plus kn
Where k is s-3
AHH yeh I don't think there's another way
Where did u get this idea from
Closed by @split pine
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
.
what are you getting in online calc
@ocean ravine Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
$$(fog^{-1})(x) = x+6 \quad \text{and}\quad g(x)=3-x \Rightarrow f(-4)=?$$
Gl1tch
I'm stuck with this question how do I solve it
first find the inverse of g(x)
Try to find what is x when g^-1(x)=-4
or that too
x - 3 right?
thats make sense too
g(x-3) = 3-(x-3) != x
so no
g(x) = 3 - x
y = 3 - x
♻️
x = 3 - y
x - 3 = -y
y = 3 - x
g^-1(x) = 3 - x
then what should I do
do I get f when I subtract g^1 from fog^1(x)
wait
f(3 - x) = x + 6
f(-x + 3) = x + 6
f(x + 3 ) = -x - 6
f(x) = -x -9
f(-4) = -(-4) - 9 = 13
found it
.close
Closed by @burnt elk
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
how do i multiply a 3 x 2 with a 2 x 2 matrix
so what you can do is multiple each row by each colmun on each matrix
that's a 2×3 matrix in green
so you can't
so start on the green matrix and multiple it down the first colmun with the first row of the red matrix
(2×3) * (2×2) is undefined
that sounds like red*green
i want green*red
yeah thats impossible
green*red is undefined.
theres not enough numbers to multiply
To multiply an nxm matrix by a pxq matrix, m must equal p, and the resulting matrix will be nxq
@polar zealot Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
thanks
.close
Closed by @polar zealot
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
I want to prove this.
some kind of base two multiplication
Do you have to prove it by multiplying the left side?
@inland oriole Has your question been resolved?
@inland oriole Has your question been resolved?
I assume that’s it bc there is an equal sign
I just would like to figure out how to convert from base 2 with a decimal point to a base 10 number
you would just multiply each digit(1 or 0). for instance $1011 = 12^0+12^1+02^2+12^3$
Karter
which would equal $11$
Karter
@inland oriole Has your question been resolved?
How do you do scientific notation with floating point IDEE 754?
@inland oriole Has your question been resolved?
.close
Closed by @inland oriole
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
hey
$\forall x\in \phi$
dark
is an always true statement since there are no elements in phi
can someone explain this better?
i dont get it
why is it always a true statement?
?
is it not always a true statement?
Do you mean if you have a statement $P(x)$, then $P(x)$ is true for every $x\in \varnothing$?
Andrew071
yes
by the way, we usually use $\varnothing$ or $\emptyset$ not phi
Andrew071
oh ok
It's true because there are no elements in the empty set. So if you say every x in E is even, but E is empty, it's a true statement
It's called vaccuous truth
Closed by @abstract badge
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
i confused myself with how i formulated it
when you put it like you did it's clear
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Does anybody know how to generate easily pixel spline (discrete, rasterised)
I read some info on topic and usually it's done with things like gradient and antialiasing
it's not like it's not dooable, but I don't need efficient one, I just simply need ANY
is there any math here
I'm asking about way of generating a spline, any curve
that goes discretly from A to B by not the shortest path
math that comes for Brazier curves is just an overkill
Yeah, I was wondering if there'll be something not so profound, but faster
@tender dew Has your question been resolved?
I come up with something like that
I know that full shift in X would be equal to deltaX and in y to some deltaY
I know that one value is higher (generally speaking)
so I loop in dimension of higher value of delta
always increment one side till it's get it's value right
and the other one can be expressed as a table or column
that is the length of higher value of delta
and is filled with ones for length of lower value of delta
now if zeros are at even distances (have usually the same amount of ones between them)
then the curve will be linear
but any change, and merge of ones into twos and so one will result in more of a spline curve
now I don't need higher degrees to represent spline - if the function will be monotonic that would satisfy me
I also wanted to get rid of something like long intervals without jump
Altough I know actions on this column would be much easier to be done with that long jump
this can be represented by any translation
Obviously this will form a triangle
after figuring sign (for direction) and which side is longer the spline might be created
if x shift would be bigger than y shift, then we'd need to switch values of L and W for algorithm, but that can be easily figured out
In this case L>W
so we can say that in a loop incrementing in longer delta gets you in that direction
and sometimes a step in other direction has to be made as well
we can express how much by this column that can be rearranged to make linear shift or to make more of a spline
rearranging this simple column by hand can get a nice spline representation
But this column rearrangement takes a lot of action
This one was done by hand
but I think there is a way to get to it by cutting column into parts. shifting, readding, and so on in 2 more loops
that's a lot of information to process
<@&286206848099549185>
I thought some random step would be needed to it and thus limit's operations but needs more complicated distribution function
but maybe that method won't bee needed
maybe some istribution over a grid
of ones
@tender dew Has your question been resolved?
maybe try asking this in #computing-software @tender dew
thanks for advice
:)
@tender dew Has your question been resolved?
you should close this channel
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Hello!
Just post your question
ok, I need help parametrizing (?) conic lines
Well you're gonna need to post a specific question
Because like with conic lines, it depends
I'm assuming with any conic you wanna make a parametric for them
I need to discover the Vertex, Focal point and director line of one of each
ok, I thought you weren’t supposed to do that in the Elipse but i’ll try
with that I should get the canonical equation right?
Wdym canonical
sorry, language barrier,
like this one in the case of the parabola
Idk how it’s called in english
I've never seen this before
Idk what the 4p is supposed to be
I can put it into elliptical/conic form
ok, so I got to this
Can anybody explain the answer to this question in a more simpler way?
Note how this channel's been taken
ok
I'm doing a different problem
I'm doing the first one
The first one
Note that the 3rd line got cut off. It's equal to -36
ok, but what should I do if i don’t have a common factor
You normally would
like in the case of the (x-2)^2
Wdym
.
ok
$(x-2)^2 = \frac{(x-2)^2}{1}$
Umbraleviathan
Hey
Hello!
What do you need help with
.
now I’m stuck with this one
ended up using these ones
Can you type out the question here
That you need help with
Cause you’re showing me a bunch of stuff
@visual dragon
I need to parametrize these lines and I’m not really sure how
“Find the Focal point, Vertex and Director line of one of each following conic lines”
Do you know how to find the focal point
a/c right?
Yea
Closed by @visual dragon
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Hi, I need help on a proof:
In rectangle ABCD, E is the midpoint of BC and F is the midpoint of AD. G is a point on AB( extended if necessary); GF and BD meet at H. Prove that EF is the bisector of angle GEH.
I tried drawing a diagram, but honestly it did not help much. I don't know if I did something wrong, but it honestly doesn't look like GEH is being bisected by EF
<@&286206848099549185>
.close
Closed by @slender solstice
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
What’s the equation that looks like this
,w plot arctan(x-10)
,w plot arctan(3x-10)
,w plot 1/(1+e^(-x))
@tacit arch I’m asking about the one that is a straight vertical line
In the middle
read this
@sudden torrent Has your question been resolved?
Closed by @sudden torrent
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Is theta obtainable without calculator
Has making linear equations in two variables worked ? ...the unknown angle opposite to theta be x so sum of angles of the triangle OCD and sum of angles of ABDC quadrilateral
Let me digest it
this is what length-chasing gives me
there is a bunch of 30°-60°-90° triangles that can be exploited
eventually you get that BCD is equilateral
@cinder sundial
here is the approximate order in which i derived these things btw
Do you use the “formula” a^2=b^2+c^2-2bccosA. To get the length of CD
@cinder sundial Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
How can i solve this for x ?
cos^-1(z) does not mean 1/cos(z)
(yes the notation is stupid i know arccos is better)
So what does it mean?
arccos just like Ann wrote.
It's an inverse trigonometric function.
When you write cos^-1 or arccos you are solving for the angle. Using the ratio.
On the contrary, when you write cos(something) you are solving for the ratio, using the angle.
Ok ,
cos^-1(x)=?
An example would help better, probably.
cos^-1(1/2) would be 60 degrees.
so, for your particular problem, you should add phi to both sides, and then take cosine.
cos^-1(x) is cos^-1(x) but
cos(cos^-1(x)) = x
so i will understand ,
cos^-1(x) gives the angel based on the ratio ,
so when we cos(angel) we basicly solving again for ration ,
that is known as x .
am i right ?
thanks.
You're good.
@charred plank Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Do you use the “formula” a^2=b^2+c^2-2bccosA. To get the length of CD
.close
Closed by @primal quest
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
A circle has a centre O and a second circle passes through O. The second circle cuts the first at two other points A and B. Let P be a point on arc AOB and extend the line BP to intersect the first circle at Q. How to Prove that the bisector of angle APQ passes through O.
I drew diagram and tried constructing multiple things to manipulate any of the basic theorems I know but can’t get anywhere
Anyone have an approach on how to prove it?
unless if i'm being stupid $\angle QOP = \angle AOP$ iff $O$ lies on the angle bisector of $\angle APQ$
jasoon
let T be the midpoint of the arc AQ, then
∠QOT = ½∠QBT
= ½∠QAT
= ½∠AQT
= ∠AOT
i hate latex
forget latex this works
Would it be sufficient to construct radii OA and OB. Then construct common chord AB and chord OP.
Then we formed a cyclic quadrilateral ABOP
sorry i don't really see what you're getting at
Let Angle OBA = x
Then Angle OAB = x since AOB is an isosceles triangle.
Angle AOB = 180-2x because of angle sum of triangle
Then Angle APB = 180-2x because they are subtended by same arc.
This means Angle APQ = 2x to be supplementary with line BQ.
Since ABOP is a cyclic quadrilateral the exterior Angle APT = x.
Therefore the bisector of Angle APQ must pass through O?
that only proves that PT is the angle bisector of ∠APQ though
@past valve Has your question been resolved?
Closed by @past valve
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Nilai dari=Score from
@fair ingot Has your question been resolved?
Closed by @fair ingot
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
hi
y_1 ~ a e^(-b x_1) sin(c x_1 + d)
please do not call me bro.
type what i said into desmos
it will run a regression on your data
and produce a sinusoid that matches it as closely as it cna
$y_1 \sim ae^{-bx_1} \sin(cx_1 + d)$
Ann
this is what you should've had
oh ok i try again
oh ok it works
but i need the formula now
ok thanks man
ill try to find it
@vale wigeon
look in "parameters"
it literally gives you the values of a, b, c and d in the formula
ohh ok thanks
also if you consider my help unsatisfactory then don't spit in my face by thanking me with "ok thanks man"
@gaunt stone Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Let a, b be odd perfect squares\
Then, a = $(2m + 1)^2$ and b = $(2k + 1)^2$, m, k $\in \bN$ (by T1)\
a + b = $4m^2 + 4m + 1+ 4k^2 + 4k + 1 = 2(2m^2 + 2k^2 +2m +2k +1)$ (by basic algebra)\
a + b = $2(2(m^2 + k^2 +m +k) +1)$

sorry one sec
it's \bN if you want natural numbers
