#help-0
1 messages · Page 738 of 1
What other forms can we use it on?
1/x is not defined for all real x. your example does not work.
you can't use lhopital's in the first place if f or g is not differentiable, lol
(II) is not true. take f = 0 and g = any discontinuous function you want
Ann i think he was providing an example to show that II was wrong
Take sinx and 1/x
learn4math, 1/x isn't defined for all real x.
you cannot have it be one of the functions for the purposes of this problem.
@dusk wedge sorry, this channel is busy right now. please move to a different questions channel or #linear-algebra.
Counter example for 2nd
Ops i made mistake
G is not continuous every where
Apology
are u guys still using this channel
apparently not
can anyone help me for this question please with solution
Use the identity $1+ tan^2 (x) = sec^2 (x)$
HELLOBELLO
than?
do you know how to subtract fractions?
ya i think
Then do it with this
$\frac {tan^2 (x) - ((sec(x) \times (sec(x) +1)}{(sec(x) +1)}$
HELLOBELLO
$\tan^2(x) +1 = \sec^2(x)$
Beluga
I just gave a hint above
Ok
oh wait, it does not work like that, answer could be -1 or tan^2(x) - sec(x)
@sage bronze
Its -1 ithink
yeah, but its confusing. According to your bracket placement it is tan^2(x) - sec(x)
should i be solving the de with separation of variables and then setting that solution equal to the kx*arcsin(x) expression and solve for k?
no you're way overthinking it
just plug in y = kx arcsin(x) into the DE and solve for k
@fleet marsh
is it really you ?
Oh
Why do we write Ax + B and Bx + C instead of A and B like with the case of linear factors?
Is it because it's one degree lower...
Huh
because B may not equal C
wait i misunderstood the question
Ax + B and Cx + D
instead of
Ax + B and Bx + C
because when we combine the dissimilar fractions, we multiply both numerator and denominator of either fraction by the denominator of the other fraction
which would indeed result in having not just the same denominator for both fractions but also a third-degree polynomial in the numerator
ohhh
in other words
so that these when multiplied give us the 3rd degree polynomial that we see on the left
got it, thanks
can someone help me
no
you still have to add the (now similar) fractions
yes, I know, but adding them won't change the degree
it won't, but (Ax+B)(x^2+2x+5) is not equal to x^3+5x^2+6x+21 contrary to what you said
not necessarily, at least
hey fellas
im kinda dumb
but i need to find x
this is the last step
and heh
im asking in a diffrent channel
oh ok
do you know how to deal with logarithms?
can you rewrite that equation as a logarithmic one?
no.....
for example
2^x = 4
how do you turn this into a logarithmic equation?
log_base (result) = exponent/missing power
ok so once i turn this into log
can you?
so write it out here
no
oh
is 8/10 the exponent of 9/10?
^
If you have a log base button... or change of base
im using casio 570 ms
find the button named log
?
i clicked the log button
smallest whole number than be split into 25%, 35% and 40% (whole number)
20
Can we? If yes, then how? If no, then why?
Yes
Hint : Area of a triangle is half of length of a side times the altitude
it's ||impossible. imagine dragging the apex of the triangle parallel to the base as far as you want in either direction; the height stays the same, and so does the area, but the perimeter can be made arbitarily large||
Heron's Formula?
Oof
heron's formula lets you find the area of a triangle in terms of its sidelengths
My brain ain't working, sorry
it's somewhat unwieldy unless it really is all you have to work with
I do not understand the big words you used.
which big words?
triangle wasn't given to be a right triangle
I dont think you can find perimeter, knowing only 1 side and 1 altitude
Yeah exactly.
Yea you cant
But maybe I can.
which big words, senku ishigami?
Well.
If there was more info
Apex, arbitarily large.
i am happy to explain what i meant, but i do not know which part(s) of what i said you don't understand.
Not enough data maybe, unless I missed out on smth
And I am lazy to google it.
"apex" in this case just means the vertex opposite to the fixed-length side.
i.e. it's the vertex from which you would drop the altitude.
Oh.
Okay.
I see.
"arbitrarily large" means "as large as you wish" or "larger than any number you could give me"
You have to make another point for it in 1 of the sides on the triangle?
Les say
Triangle ABC.
And les say
We take the height from angle A.
So it has to land somewhere on angle BC.
So that point.
Will be the apex?
Oh. What is it?
Woah this is SICK!!!!
it is extended until it meets the straight line which contains BC
But big :|.
that is how you determine its length
Yes.
I mean thaat.
here is an illustration, albeit using different notation than you.
Hmph?
dragging C along this horizontal line will not affect the area of the triangle, no matter how far you go
however, the perimeter of the triangle will increase, as should be obvious.
also, regarding heron's formula
Would not it be this line?
i did say this
yes, what you have drawn is an altitude.
here is what an altitude may look like for a very 'stretched-out' triangle, for lack of a better word.
can you please help
Wow you were so smart in 8th grade then @vale wigeon ?
eh?
can you please help?
A+B+C = 180 degrees
B+C = 180 - A
(B+C) /2 = 90 - A/2
I dont remeber what exactly sin(90-A/2) is, but there may be a table on which one would that be
did i say so at any point?
a/2 is in all options
i didn't??
There is a table what sin(90-x) is equal to
sin(90-a/2) = cos(a/2) ithink
So I interpret from that information that you were very smart and intelligent when you were in 8th grade.
sin(90-x) = cos (x)
Yes you do?
Then I guess that would be the answer
the "yes" does not apply to your calling yourself dumb.
Just appreciated you anyway.
if it did, i would have said "yes, and what you have drawn is an altitude"
yeh cos a/2 is answer, thanks
but the lack of this and changes the meaning of my sentence enough to make it so that i take no stance at all on your dumbness, senku.
like anonymity allows people to say whatever they want
And I am dumb, even I know Lmfaoo.
i don't appreciate having words put in my mouth, i will say that much
1 mark??
i did it using the cross product
since its 1 mark there must be an easy way to do it right
that im missing
yes, using the cross product
is there no other way
consider certain properties of a parallelogram
and you should be able to get the area from something you obtained earlier
did you do the area of the parallelogram/2 for part b?
no i did 1/2ab sinc
and i found the angle c using the dot product
truth is the cross product isnt even in my course xdddddd
they just gave u what u need lol
yes i realized that
Please tell me
Sec theta + tan theta =x, then what is relation of sec theta - tan theta in terms of x
can you send screen shot please?
Okk
Can somebody help me on this one?
I need to find the vector which is a linear combination of x1, x2 and x3
UP
what have you tried?
i computed all the combinations of x1, x2, x3 and the other ones in an online calculator, and all of them are linearly dependent
surely your textbook or teacher taught you a method for finding linear cominations of vectors?
im studying on my own
Please support my work on Patreon: https://www.patreon.com/engineer4free
This tutorial goes over how to determine if one vector is a linear combination of a set of vectors. It is part of a full free course on linear algebra.
Links:
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i cant figure out a way to do this without just trying all the combinations in the answers
and seeing which ones don't have contradictions
??
maybe you can do a matrix with a determinent of 0?
It would be a 4x3 matrix
the co-efficient matrix will have det of 0 by FTIM since it's somewhat implied {x1,x2,x3} isnt a basis of R^3
ohh got it
x3 is a combination of x1 and x2
then i can do a matrix with x1, x2 and the other
since x3 was the linearly dependent term, it was obscuring the result
Answer is letter C
All the others span R3, so they are independent, and only C spans R2, so it is dependent
@alpine sable you have the solution on paper?
like with the method and stuff, wanna practise some vector stuff
ye
was wondering if there was like
a more systematic solution
like using a b c as the third vector
but this is simple enough
thanks my dude
To find the dependent vector you could make a system with the 3 eq if you didnt figure out just by looking
sounds reasonable
No problem my man
i have this issue. gotta find AD lenght.
It's not that hard as a problem i think but don't remember the formulas or the theory.
Anyone knows what can i look up for ?
i don't even know what to look for tbh
maybe doing a proprotion with the angles ?
First, is this drawn to scale, because that 45 degree angle looks really wrong
And that is not the best way to denote 90 degress
Ofc is not to scale as it doesn’t really matter
As well as u denote the 90degrees
How that even matter ? Lol
It does matter because if you labeled that angle as 45, then the other angle at point D is 135 degrees and that does not work at all
And for this, the convention is to denote like this, with the square looking symbol, not an arc
I had to get it the correct info first
so, what can i look up for ? what formulas ?
can someone help me out with this question?
i know one of the answers is 6arcsin(5/8) / pi
but I'm not entirely sure how to get the second answer, do I just do the same thing but 6 - 6arcsin(5/8) / pi to have arcsin by itself?
Of the lower triangle, you have all 3 angles, and one side length, you can use the sine rule
if ADB is 45 degrees, then so is ABD, hence AD is the same length as AB
Actually, the triangle is 90° 45° 45°, it's isosceles, AD = AB
Yeah what they said
uh should i take my question to another channel?
Yes
gotchu
An inactive channel
ok let's do a step back because in scale u can see what i mean
difficult
to write on pc
draw*
the scale is around the height being 6 times the base
Since triangle ABD has a right angle and angle ADB is 45, you can conclude that angle ABD is also 45
Therefore making it isosceles
If you are using chain rule here
what happened to the tan in the 2nd time differientating the inside?
Ask in an inactive channel
????????
u cannot conclude that what the heck
u can even see it
Yes you can
all right i understand gonna move to someone that knows what is talking about
Sum of angles in a triangle equals 180
woah
what kind of question is this
@north goblet calm down, all you do is play arknights man
we gotta evaluate math step by step
So 180 - 90 - 45 = 45, therefore ABD is 45 degrees
I know what I'm talking about, you don't apparently
Not to make anything bigger than it is but it's so funny to me that a person joins a math help server, gets told a triangles angles sum to 180, then just denies it and leaves
@obsidian cave what do you mean the earth is obloid and not flat? blasphemy I say
lmao what is going on in this channel
How do you make a 3d function of 2 variables that has at one point a minimum in one direction and a maximum in another direction
On an obloid earth the angle sum of the triangle is 270
lmfaoo
Or it can vary actually. It just has to be greater than 180
Angle sum on a sphere is 180(1+4f) where f is the ratio of the enclosed surface area to the area of the sphere
So if f is small it approximates euclidean geometry
log_a(b) = log(b)/log(a)
okay, i feel like this should be easy but im so confused
i've got a table of user's percentage who use certain programming language
how can i know the given population out of it?
for example c++ is used by 12%, c# by 3% etc etc
and what do you want to find?
if you know the total population you can just multiply it by the percentage
eg if 150 people took your survey, 150*0.12 use cpp
I am not sure if high school level stuff is allowed here but I need some help with this!
I need to find the inverse function of this, but I have trouble solving it for x... Can somebody help me?
high school stuff is most of what populates these channels so its definitely allowed
what have you tried so far?
I played around with properties of logarithms and exponents to see if I could get anywhere but I keep getting stuck...
I simply rewrote the function in different ways like
e^y = (e^x)/ (e^x-1)
And much much more forms that wouldn't help me get anywhere
,w inverse of y = x - ln(1+e^x)
I'm convinced that wolfram alpha is wrong here, If you put both functions at desmos you can tell that is not the correct inverse
,w simplify e^x/(1+e^x)
ah there we go
According to my book the correct answer is f(x)=ln(e^x/1-e^x)
this only has one variable, and should be easy to invert
i knew that simplified somehow
but I can't myself get to that
divide each term by e^x
once you get them all in one log
$y = \log\frac{e^x}{1+e^x}$
bunny
multiply the fraction by e^(-x)/e^(-x) to get what Wolfram gave you for simplification
can you get the rest @winter token
Hope so, wish me luck :Ρ
i can latex it all out if you need, ping if you do
latex?
the typesetting
like this
That would help yeah
I am just kind of lost on where I start in this I don't need the entire procces
okay one sec
$e^(x-y) = 1+e^x$
-KlariNoX-
wait what is this
This is as far as I got, (x-y is an exponent)
i dont think we want this
no we dont
ok here we go
Original thing is
$$y = x - \log(1+e^x)$$
right?
bunny
yes
do you agree that is equal to
$$y = \log\frac{e^x}{1+e^x}$$
I need to solve that for x to find the inverse function
bunny
using log rules
Uhh... which rule is being used here?
$x = \log(e^x)$, then using that $\log(a) -\log(b) = \log(\frac ab)$
bunny
ohhh thats genius
yeah I realised what you did now
I think I got it from here, Thank you so much!
okay now we want to simplify our $\frac{e^x}{1+e^x}$ by multplying it by $\frac{e^{-x}}{e^{-x}}$ to get $$\frac1{e^{-x}+1}$$
bunny
@ionic jewel I was able to solve it, though I have to admit I probably wouldn't have if you didn't show me how to simplify that fraction in the last text 😅
Thanks a ton for the help! I've been scratching my head for hours on this problem
You're welcome, glad it worked out!
[Laplace transforms, Control Theory, Electronics] I'm trying to figure out why I need to subtract LsI_2 in eq1 and LsI_1 in eq2. It looks like I_2 doesn't run through the inductor why do I need to subtract it?
I don't recall much about circuits but this looks like mesh analysis, do you know how that concept works?
Can someone explain tan to me? (Imma move this to a diff channel cause there’s a discussion I realize)
yea it is mesh analysis. I am reading a textbook and this is an example problem... just trying to figure out how they got there
actually I got it... it makes sense because I1 and I2 are closed loops which I didn't think they were
So in meth analysis, in that example the current convention is ccw, where the arrow enters the component, it's positive, and the other side, it's negative. So in the left loop, I1 enters the component so positive, while I2 enters from the opposite, hence negative. In the right loop, I2 enters the component so positive while I1 enters on the opposite so negative
is my math right here?
im fairly confident but at the same time i couldve overlooked something
<@&286206848099549185>
not completely
look at your second line, the implicit derivative is wrong
try to fix it
you mean the cos?
also the cos, I didn't understand if it's argument is a x
of if I'm seeing things
but more specifically the h/4600 derivative
what's wrong with it? seems right to me, dh/dt is the speed of the rocket
the speed
No, what's the derivative of the variable h?
It's dh/dt.
So, it's 1/4600 dh/dt, not h/4600 dh/dt.
That's one error.
The other error is you have tan(theta).
Somehow theta becomes x.
The derivative of tan(theta) is sec^2(theta) dtheta/dt.
ah somehow changed that
then remember some trigonometric identities
deriv of tan theta is also 1/cos^2
so something more like this?
also i did forget to do pythag for sec/cos theta last time just realized
Yes, except minor error, the cos^2(theta) is missing the closing parenthesis.
gotcha
oh srry will do
okay here's the revised version
the number does makes more sense in terms of the question
@oak chasm how's this
You can't get 0.75 from a number about 1/7 times a number less than 1.
Also, it's probably radians instead of degrees.
well that part is about 0.147
You're going to get a number close to 1/7 times 7/9 or 1/9.
well idk what i did wrong considering those are the correct numbers
maybe i could change the unit to radians
instead of degrees/sec
,calc 68/460 * 2116/2792
Result:
0.11203438395415
680 not 68
Yes, 680/4600 = 68/460.
oh right
So, 0.112 radians per second.
How did you get 0.14?
,calc 68/460 * 2116/2792 * 180/pi
Result:
6.4190973609213
6.42 degrees per second.
thanks, turns out i forgot to multiply the two numbers and the 0.75 comes from the 2116/2792
can't believe i made that mistake
yes
I’m learning about toolkit functions never heard of it
What are they
(via self studying a pre calc testbook)
a quick google search yields this https://math.libretexts.org/Courses/Monroe_Community_College/MTH_165_College_Algebra_MTH_175_Precalculus/02%3A_Functions_and_Their_Graphs/2.03%3A_Transformations_of_Functions
you also could use #precalculus to debate some more if someones interested
then you open this channel to another questions
Is self studying math good?
At least to get the basics in
the best thing you can do for sure
this feels like a really non-sequitur reply
That’s literally the textbook i’m working in
lmao
what a coincidence
it was the first google hit
but yes self-studying math is good i guess???? it depends heavily on what youre studying from
openstax pre calc textbook
That good
I understand learning from a course(a textbook is a course in book form)
Depends on how good the course is
and how much human feedback you have
(mine is from here…..)
but this is the information I have
I have gotten to the stage where y/2x = 1
but can you tell me what the math principle is for this?
Not the answer, just what it's called.
I want to solve this myself as I'm sure it's not difficult
Good luck with it
But what is this called?
a good chunk of algebra is governed by the same principle
"do the same thing to both sides"
in your case, you can multiply both sides by something to progress towards the solution.
the teacher gave me this link:
https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:solve-equations-inequalities#x2f8bb11595b61c86:linear-equations-variables-both-sides
but that doesn't help.
you are familiar with "do the same thing to both sides", yes?
what does in terms of n mean?
I can’t help this person unless I know what that means
Yes, I'm familiar with it.
The issue is that y numerator.
'solve for x in terms of y' means the same as solving for x, except that the answer will be an expression involving y rather than just a number @native temple
but also you don't need to interrupt
@floral willow well why not multiply both sides by something?
okay
Yes, I understand, but I'd like to read a link about it.
give me a minute
I can't find it in Google.
It will stick better if I have a guide to fall back on.
mm
i cant think of any guide to give you here unfortunately
this is the sort of stuff you learn by doing rather than by reading
hmm, there must be some guide about this type of problem.
I mean, I already have the solution, but that doesn't help me if I don't understand the mechanics of the problem.
Imagine telling me to delete my hint, when they have the full solution in front of them 🤣
Well, I was trying not to look at it, but since no-one is aware of any guides for this, I felt I had no choice.
But I did try not to look at it and solve it on my own.
"Rearranging algebraic equations" is the lesson title
ok, let me try to google that, one sec.
Yes that's similar
What specific link were you referring to?
Here’s how to solve step my step
the principle of algebra is the golden rule
to do operation $n$ on $ Expression A$ do operation n on all sides of expression a
Nerdy_Coder
in other words simply do operations on all sides
like with fractions
to convert s fraction to it’s equivalent operate on both numerator and denominator
I think I finally found a link:
https://serc.carleton.edu/mathyouneed/equations/index.html
I think what I was missing was this rule:
RULE #2: to move or cancel a quantity or variable on one side of the equation, perform the "opposite" operation with it on both sides of the equation.
oh
Next is this -> "Solve for x in terms of y"
I think I can feel how to solve this problem, but I don't know how to explain what it means.
I'm trying to search for a link now.
thank you for the help!
hey i need a help for my assingment can someone help?
,w complex conjugate of (z-i) = 6-2z
so my solution was wrong D:
dont ping
is there an explanation of how this solution was derived?
because I've clearly gotten
not sure how Wolfram went from that to z = 2-i
that's basically what I was trying to do yeah
is implicitly saying z = x+yi incorrect?
I was just going off my notes which says that z* + z = 2x
based on a conjugate of x+iy + x - iy = 2x
The abscissa of the point R that divides the line joining the points A(2, 3) and B(7, 3) in the ratio 3:2 is???
@dusk schooner channel busy please move
aight
@faint steeple if you introduce the variables x and y for the real and imaginary part of z then you have to do so explicitly
otherwise nobody will know where this mysterious x comes from or what it has to do with z
ah, I see...
let me go back and try my solution again with explicit declarations then
and also in full as you said
thanks 🙂
may be back in a bit if I need help
channel's free now
Given that 0 < a < 360, then the equation sin(a) = cos(a) has how many solutions? How would I work this out?
||45°,(180+45)°||
Do u know the geometry of sime and cosine in unit circle
Convert the problem into an equivalent problem, we may divide by cos(a), where cos(a) is non-zero. Then we can answer the equivalent question tan(a) = 1 on the interval 0 degrees <a < 360 degrees.
Would it then be four? It's equivalent in four spots
No, u have to notice abt the signs in the 4 quads
Oh, 2?
How do I solve this, not the answer, just how do I figure it out?
first consider setting up a fraction
Understanding that billion is 10^9 might help.
then express 75billion in scientific notation
and apply exponent laws
I appreciate it but this is a question for my daughter and I have no clue how to even work it or what you guys mean, can you explain the steps?
no
nope sorry, like I said all of this is new to me.
yes foreign to me sorry, like I said trying to understand to help my daughter.
it would be a lot better if we could get your daughter on the line, but i suppose she may be too young
this is going to be very difficult
because you would basically need to learn about exponents before even beginning to approach this problem, as understanding scientific notation is impossible without understanding exponents.
trying to think about where to begin explaining this...
I think you should direct this to a teacher or something.
There's only one way for you to be able to do it, learn maths yourself. I can give you resources but it will take you a long time, more than you are willing to commit, assuming we're not being trolled.
True but her teachers are not available. but again ty
khan academy is decent for learning basic stuff like this. the key words are "exponents", "exponent laws" and "scientific notation".
Get her on the line, she can't be that young if she's learning about scientific notation...
she may well be 11 or 12.
They don't teach nothing in the UK then, I didn't see that till college (16-18 years old).
I definitely learned scientific notation in middle school, so something like 11-13 sounds about right
but it was in some sort of intro to science class or something, not in algebra iirc
(I told you, they don't teach nothing in the UK, what is going on.)
Maybe they did and I just forgot.
yes
I can try to give a brief explanation, but it will likely be specific to this kind of problem
Exponents are a shorthand way of writing "i want to multiply something by itself N amount of times". For example, 2^4 is the same as 2x2x2x2 which is 16.
On an unrelated note, its hard for us to comprehend really large numbers quickly. For example, if I told you to multiply 10 million by 20 billion, how could you do this in your head?
One way to do this is to try and write large numbers in a shorthand, easy to understand method, usually with some estimation and "rounding". 2,345,678 could be estimated as 2,300,000 which is the same thing as 2.3 x1,000,000 (2.3 million)
I would start here:
https://www.khanacademy.org/math/in-in-class-7th-math-cbse/x939d838e80cf9307:exponents-and-powers/x939d838e80cf9307:large-numbers-in-standard-form/v/scientific-notation-old
If you don't understand that, then start at the very beginning of the math section.
It starts with 1+1 = 2, I think.
If you notice something about multiplying by 10s, each time you multiply by 10 you simply add a 0 to the end of the number. So 1,000,000 has 6 zeroes, and is thus equal to 10x10x10x10x10x10, or also 10^6.
If you convert large numbers to this kind of format, it makes dealing with large numbers a lot easier. That last time about 10 million x 20 billion? Its the same thing as 10^7 x 2 x 10^10, and now you can simply count the number of 10s and get the answer of 2×10^17.
ty all for trying to help, I am going to take your advice and look at khan.
Good luck!
Khan is good enough for beginners from what I've seen so far, although it would be much better with real world applications. But then again, there are hardly no textbooks that cover real world applications. Anyway, be sure not to skip around, as the concepts build upon each other.
Is the second variable numerator a fractional exponent?
You mean the $v_0$?
dldh06
Hmm, I'm not sure how to write it.
$v^2_0$
That's a v with a subscript zero, known as naught
bunny
So v naught
oh is that how you spell it lol
Yep
,w naught
dldh06
I don't know what to do with it.
What do I search in Google to research this math process?
I tried "v naught", but it showed Physics.
dldh06
Hmm, this is confusing, but let me try.
It's just a variable, that's it
I'm stuck at:
$v^2_0$ = 1/-5x_0$
Willow
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
What happened to $v^2$?
dldh06
Willow
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
Like I said treat $v_0$ as a variable
dldh06
So like $y^2$
dldh06
I still don't get it.
Any links to other examples, maybe?
Or at least the name of what this part of math is.
I know it's "v naught", but that doesn't yield results in Google.
If you had $v^2 + y^2 = \frac{1}{-5x_0}$, how would you solve for v?
dldh06
It's just isolating variables, but with different variable names
let me try the example you just posted
The example I posted is exactly the same as what you have, I just used a different variable
Also, why do you have divided by $-5x_0$?
dldh06
That's wrong
The opposite of $v^2$ would be the square root, yes?
Willow
Yes
Does that fall under the Law of Exponents?
Not sure what that's exactly called
I don't know how I remembered that either. But I'd like to update my notes.
I don't see it listed here:
https://www.mathsisfun.com/algebra/exponent-laws.html
Hopefully, someone comes along that knows what its called.
It's just known that the opposite of squared is square root
What's actually happening when we 'eliminate the third column'? I really don't get this (trying to put something in RREF for Linear Algebra)
Ask in a different channel
What's the term for the opposite operation of addition is subtracting?
I mean, you can apply law of exponents for that
Back to this problem you posed.
I'm stuck at $v^2 = \sqrt{\frac{1}{-5x_0}}$
Willow
Where's the y?
I don't know what happens to it.
but one second please, an additional video resource was just posted to us students.
I'm going to try and watch it to see if it helps me understand.
On what specifically?
On this problem
Not your problem, but the original problem I posted
I guess other students were also confused
let's see if it helps
Like I said, those are just variables
Does this mean that the probability of X1, X2,.... of occurring is p?
and that the distribution is geometric?
No, means X_i is distributed with Geom(p). iid means independent and identically distributed.
It is
Using variables and operation symbols, express each of the following verbal statement
The product of two successive odd number is 35
someone help me with this, my tiny brain is so confused
How can you write an odd number? How can you write the next odd number? How can you write a product is equal to 35? Just combine all these and you are done.
yeah its answer is x(x+2)=35
but i am not getting the numbers with solving this!!
what are you getting?
or am i doing it wrong
the numbers which multiply to 35 are x and (x+2), as you should remember from the equation you wrote yourself.
how can we put if on the equation tho?
what do you mean?
You found x=5 is a solution - then the pair {5,7} is a solution for example
okay so we put one at one time lol sorry
you used the letter x for the lower of the two numbers you're multiplying
the other number is x+2
you should have understood this much when writing the equation
i was getting confused cause i was thinking to put both of them at once
Hey
find two different paths, with the same start and end points, such that the integral of F · dr along one path is not the same as the integral of F · dr along the other path
yeah the part im stuck with is i don't know how to find two different paths
sorry i still dont understand :/
@native cloud channel busy please move
@limpid aurora you have a lot of wiggle room here lol
pick any two points you like, literally any two points
and connect them with two different paths
you might, for example, go with the straight-line path
or a three-segment path which first goes parallel to the x-axis, then parallel to the y-axis, then parallel to the z-axis to get from the first point to the second
those are just some examples of the possible paths you could take
don't overthink it basically
do you want me to get you started with some example paths
yes pls
take A = (0,0,0) and B = (1,1,1)
the straight line path from A to B: r(t) = (t, t, t) where 0 ≤ t ≤ 1
the 'parallel to axes only' path from A to B: r(t) = (t,0,0) for 0 ≤ t ≤ 1; (1, t-1, 0) for 1 ≤ t ≤ 2; (1, 1, t-2) for 2 ≤ t ≤ 3
a twisted path: r(t) = (t, t^2, t^3) where 0 ≤ t ≤ 1
please note that you do not need to take these exact paths. if you think you can see a path that makes calculations easier, then by all means go for that instead.
and don't overthink it.
Hey, i also attempted this ques , but taking the odd numbers as 2x+1 and 2x+3 , odd nums can also be represented like this but then the answer that comes after putting solutions of x , is wrong. Can someone tell if there's mistake?
can you show it to us?
you're conflating the zero product property
ab = (something that isn't 0)
doesn't necessarily mean that a = that something or b = that something
well you have a quadratic equation, (you could solve that using appropriate methods)
however
since you're looking for consecutive odd numbers,
you should be able to find the solutions relatively easily in that form from the factors of 35
using complete the square is also another way ,ig
alright got the right answer, thx for pointing out my mistake
anyone know how I can start this question? It was in our end of year exam (first year robotics) and i had no idea how to start it as you cant seperate the variables to diff sides easily?
i obviously gave it a full page try but looking back through notes i dont think you can just open up with a divide by tan x llol
hm maybe I could subtract y then factorise the right as y(2secx-1) ?
and divide by (2secx-1) might go try that while waiting for a tip here 😄
ok i definitely can't do that 😂 typing without thinking...
feck this question 😂
@turbid harbor Try multiplying the equation by cos x
shall do 😄 ty
tanx is sinx/cosx no idea how this is gonna hellp but i trust you 😂
ooo ok
clever
Got it then?
i think so TY 😄 definitely got a route to go down
Are you guys finished?
that means you're learning 😉 shoot the question
the equation for gradient is m=(y2-y1)/(x2-x1)
6-2/3-1
yes i think 😄
change in Y over change in X is an easier way to remember it imo bc then you know you need to subtract the ys and xs without looking at weird symbols like y2y1 😛
easily done!
Gradient is 2
you got it 😄
@turbid harbor let’s try with one more
then try again in a day or 2 and in a week and a month to drilll it into your long term memory 😉 (something im bad at personallly but working on)
looks it bro! im a lowly first year uni student who did A levels 8 years ago and only brieflly touched on this stuff in first year 😛
so dont take my word as gospel, but yeh pretty sure you got it
Lmao im yr 9
you could always use an online checker to double check your answers
And i keep being confused in the arrangements
impressive mathsing like this in year 9!
just keep practicing, you're setting yourself up to do well in maths in the future 😄
our university teacher for maths said to switch around topics more, as its easy to be "on a roll" on one subject and just forget it if you dont repeatedly do them
Alr thanks
:)) GL
definitely don't got it, gonna go watch videos on implicit differentiation tbh 😂
After the hint you should have sin(x) * y' + cos(x) * y = 2
With the equation in this form it's not too hard to realize that you should look at (sin(x) * y)'
im gonna write some of these on post it notes around my house bc i reallly need to remember to llook for them more
You can also just divide by tan(x) and do the usual process to find an integrating factor for equations in the form y' + p(x)y = q(x) but you'll end up with the same result and it's more tedious
it's bad that "y' + p(x)y = q(x)" confuses me 😂
got a feeling second year maths I will be coming in here crying a lot
:3
@wary stream My current answer is $v = \sqrt{5x_0+v^2_0}$
Willow
Could someone help me with Nonlinear Differential Equations and Stability? I don’t understand the bottom part of the solution. I know how to get the determinant and the trace but how do we know that it is the only critical point and that it is ass. stable spiral point?
i am not too good at this but critical points are points where both x' and y' are 0, in this case you get 2 simultaneous equations which give one solution x=2 y=3. As for the type of node you need to look at it's position in the trace determinant plane:
this one lies above det(A) = 1/4 (Tr(A))^2 and to the left of the y axis so it's a spiral sink
That is a great explanation and picture :). I just didn't copy the last part, is my plot wrong? It looks like a spiral source to me
no the plot plot of the soutions is different to the diagram i gave
you plotted on the x-y plane and the diagram is of the trace-determinant plane
Ohhh I see, my bad
no worries
Yea I recognize the D T plane picture
I’ll look more into it now, thank you for the help
welcome
What is confusing you?
Do you know how to find slope for a given equation?
Yes
Yeah so gradient is just another term for slope
you said you knew
Do you know how to find slope for a given equation?
Yes
To find the gradient its y2-y1/x2-x1
assuming you intended the appropriate parentheses,
that's the slope from two points, not an equation
Yeah this is when you are given the two points
are you familiar with the slope-intercept form of an equation of a (non-vertical) straight line?
Not really
y = mx+c
many other places use b instead of c
is the equation of a line in slope-intercept form
it is called the slope intercept form because the slope and the y-intercept can be read from that equation directly
well so that’s the equation correct?
Isn't the point of this question to introduce slope intercept form by having them find gradient from rise/run and relate that to the equation? part b asks you to find a pattern that is obviously meant to be discovering slope intercept form
i don't think they're supposed to be looking at the equation for a), just the plot of the line
ig
in that case, choose two nice points on each line and apply the slope formula, and/or rise/run
Any points?
what i initially mentioned applies to part b)
(3,3) and (-5,-1) but yes
please use appropriate ()
yeah thats it
cool
log 3.109 is equivalent to log 31.09 × 10^-1
then you use logarithm's multiplication rule (rule 1) to separate 31.09 and 10^-1
so you should get log 31.09 + log 10^-1, using the power law, bring down -1
then its 1.4926 - 1, so log 3.109 = 0.4926
oh uh thankyou vm
ah yea i saw the other channel HAHA sorry
never mind 🙂
is it true to say that if A=2n, B=4n (n in N) and B subseteq C subseteq A
then |P(C)|=א?
and is it true to say that the power set of all infinite size subsets of an א_0 sized set is size א ?
i made a ski resort on a map, the ski resort is 200cm long on paper, I need a conversion for every 1 cm = x km on the map, i need it to be more than 80km in total
need help asap
im trying to find out a website to figure it out for me but i cant :((
if you take 1 cm = 0.4 km then for 200 cm you'll have 200 * 0.4 = 80 km
I don't understand the more part tho
homie can you reask the question powerset of a finite set is also finite
thank you so much, i hope everything goes well for you
is this channel taken?
n in N is implied
c meaning what here
continuum
whats that
size of reals
so.. א?
no
the wiki page says its א
if by aleph you mean aleph_0
aleph_0 is the size of naturals
2^(aleph_0) is size of powerset of naturals
א_1
which assuming CH is aleph_1 = continuum = size of reals
so it is true then
right
which = א
WHAT DO YOU MEAN BY ALEPH
the size of c
aleph is not size of anything


