#help-10
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i forgot about the theorem
so then x would equal 16
i have one more question, is that okay?
ok
what 🥰
@mighty carbon Has your question been resolved?
<@&286206848099549185>
the height of the equilateral triangle is 3
use that to find the length
wait no
I meant 9
wait what question are you trying to do
I just wanted to check the first three and I didn't know the last one
is the perimeter 9?
nope
consider triangle AEC
you got all of its angles and its height
you can use trigonometry to find it's hypotenuse
@mighty carbon Has your question been resolved?
Do you still need assistance on this question?
I could help while I am waiting for a helper to help with mine (:
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hi
@mild stag Has your question been resolved?
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does this method work for every 3x3 matrix that has a determinant
ah
beware that it doesn't work for 4x4 or larger matrices
yeah i got that
seems too simple to not have been taught first
if it worked for every 3x3 matrix
thank you
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I need help understanding the monty hall problem
what are you understanding?
Ok
typo
So I watched the scenario with 100 doors and after the first round the host takes away 98 doors
yes
I get that on the next round the door you chose has a 99 chance of being wrong still but I dont understand how the other door wouldn't have a 99 chance too
the other door havae 99% chance
what do you mean
the original door have 1% of being right and switching the door have 99% of being right
How
so if you choose 1 door out of 100 doors you have 1% of being correct
Yes
if you choose 1 door, open all wrong doors and switches
then you will be correct if the original door you choose is wrong
which is 99% of the time
Yes but the other door only had a 1 chance of being right in the first round as well
How
because we eliminated all the wrong doors
if I roll a die, what is the possibility of it being 6
if I give you additional info, for example the result is even, it changes the probability
it is called conditional probability
Yes
But
The chance would still be 1 percent for both doors out of 100
The door you choose and the one not eliminated are essentially the same right?
Like
the doors opened are the WRONG ones EXCEPT the original door and the correct door
Yes
nice
the probablility of winning if you dont switch is 2/3
and only if you picked the correct door, a random wrong door is opened
and you have 1% of getting the right the first time
that's probably all we can teach
I still dont get it
Let's say I chose the car first time
Then the middle goat is gone
It's still between the goat and the car
And vise verse
initailly:
probability: 1%
probability of failure: 99%
in the end:
2 doors but the first one still has the same probability
but the second door has the remaining 99%
or you can just brute force it
like in this diagram
but dont do that for 100 doors 💀
also watch a yt video!
@languid arch Has your question been resolved?
@languid arch Has your question been resolved?
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Hello sorry i was to late to reopen the channel just had to do something suddenly Ill just post my question here again
Taylor series expansion of this function about a= -3
I managed to get this answer
Here are my derivatives. sorry kinda messy
The thing that was bugging was that this was a practice problem on our textbook and its answer confuses me
the textbook's answer was similar to this but its denominator had 6•3^(n+4)
i have no idea how that 6 got there
I dont know if the textbook has a wrong answer or im just dumb asf to realize what went wrong in my solution
@flat snow Has your question been resolved?
If u look at ur solution for example, for the first red circled its 5!
and the second circled it didn’t take into account the /3!
i havent put the n! at the denominator yet
i was solving the f^(n)(x) first
This is my f^(n)(-3)
then i put this in here
after simplifiying, this is what i got
i still have no idea how there is a 6 in the denominator of the supposed answer in our textbook
oh wait i think i got it
.close
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Could someone explain to me why Void is always a subset of any given set?
void as empty set?
The empty set contains no elements. A set A is considered a subset of another set B if every element of A is also an element of B. So empty set is a subset of any set because it has no elements, and the condition for being a subset is automatically satisfied due to the absence of elements.
thats the best i can explain it
@hardy coral Has your question been resolved?
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im having trouble isolating a
once i substitute it into the function using f(b)-f(a)
show your work
it seems like you didnt integrate
isnt it f(x)x' - f(a)a'
,w integrate -10/x^3
what about a
how do you differentiate x
thatw ould make everything 0 cause they should be constants
@echo jackal Has your question been resolved?
x would be a constant here
isnt it a variable tho
$\int^x_af(b)db=F(x)-F(a)$
yes
Arctic
are you able to tell me how u got 5/x^2
@echo jackal Has your question been resolved?
Can u go step by step for me
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You are having a conversation with your friend, who is trying to convince you that since ordinary traffic is about 60 decibels and a rock concert (with massive speakers and amplifiers) is 120 decibels, you don’t need to worry about your hearing at the concert since a rock concert is only twice as loud as normal city traffic.
Using your knowledge of the decibel scale, explain to your friend why this reasoning is wrong.
Is the difference supposed to be that big or m I tripping?
Not twice as loud, but 1 million times louder?
$$ I_{0} = 10^{-12} $$
kai_funaba
"how loud is something" is kinda subjective
but yes 120dB has waves that are 1 million times stronger than 60dB
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I have a few matrix questions
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what's the proof that y^2 = ab?
!status
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2. I have begun but got stuck midway
3. I got an answer but I'm told it's wrong
4. I got an answer and would like my work checked
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6. None of the above
?
1 2 3 4 5 or 6
what have you tried?
i dont have any idea, i thought about the pythagorean theory, but it doent work, cause there is multiplications, and not the additions
You need to use similarity
hmm is it like:
start with labelling any angle as theta and try to find rest of angles in terms of theta
$\frac{y}{a} = \frac{b}{y}`$```
pl_ans_me
did you find this using similarity or you're just guessing
use pythagoras theorem on 3 right angled triangles, which will give you 3 eqns from there you can eliminate variables
I am not really sure if i used the corresponding angles
does this makes sense?:
opposite side to the 🔵 angle opposite side to the 🔵 angle
------------------------ [left part of the triangle] == -------------------------- [Right part of the triangle]
opposite side to the 🔴angle opposite side to the 🔴 angle
does this make sure that I am using the corresponding sides?
.close
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Hi, I was wondering why we can assume that density is 1 in this example?
to be honest, I don't think it's a good practice to do that, but since it explained that
when we are calculating M_x/M and M_y/M, the constant density would be cancelled out, therefore you can take the density to be any constant without affecting the final answer
Oh, it just devides out of the mass and M_x
thats kinda stupid but yeah i get it
so we just assume its one because it makes no impact on the answer as it crosses out on the final step
we assume it's one because for "the ease of calculation" and yea, it will be crossed out in the final step
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how can i increase and decrease percentages for example increase 24 by 5%
<@&286206848099549185>
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and also
ok
if you have done anything, you can post it out so that we can have a look
24+5% of 24 5/100x24 . cancel 100 until 4
ohh
29?
so it's 24 times 105%
nope
try and work out the math
24x105%?
24×105%
ye
24×(100%+5%)
=24×105%
=...
2520
did you forgot something?
percwent
yea
2520%
yea, but do you know decimals/fraction?
ye
try answer in decimals 👍
2.0
.
oh great
yea?
power cut sor
no worries
2.52
nah
25.2
you moved a digit more than it should be
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Is it correct to say that x^2-t, the minimal polynomial of \sqrt(t) on F_2(t) is not separable?
I need to show that the extension F_2(\sqrt(t))/F_2(t) is not a Galois extension.
consider the derivative
I didn't understand what you mean
do you not have a lemma about separability vs the relationship of f and f' ?
you need to argue why x^2-t is not separable
Perhaps but I didn't know it then 🤔
something about gcd(f, f') ?
I have to go now. head over to #groups-rings-fields and also ask there
ok thank you
@tight wadi Has your question been resolved?
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Can I get some help with matrix qudstions?
Express both of b and c in terms of u and v and find their dot product
what do you mea
Oh
as in like
b = u + 2v
c = 2u + v
what do I do njow
@sage geode
Take their dot product
and then what
And then calculate it using the given information
That's the same question
What's your question?
where are you stuck on this question
the most recent picture
No shit
I just don't know where to start
Do you know how to find the distance between a point and a plane
@pearl charm Has your question been resolved?
No not rlly
how would I do that
<@&286206848099549185>
<@&286206848099549185>
.close
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,rotate
@timid silo Has your question been resolved?
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the question asked to evaluate
!status
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6. None of the above
Use the theorem log(a)/log(b) = log_b (a) where log(?) is base 10.Use a calculator to finish off calculations. Alternatively observe 27 = 3^3 and 4^(1/2) = 2. From there you can use the theorem (a^b)^c = a^(bc).
this is your teacher's work?
i dont get why there is 4^2 on third line and also why there is 9^1/2
$\log_4(8) \neq \log_4(4^2)$
yes
Ann
your teacher fucked up
seriously?
unless this was some kind of elaborate "sPoT tHe MiStAkE!!!!" thing
8 is not 4^2
4^2 is 16
bruh lmaooo no wonder i didnt get it
Ann
to what power do you need to raise 2^2 to get 2^5?
uh multiple 2 cubed?
doesn't answer my question.
2^2 raised to what power gives 2^5?
$(2^2)^x = 2^5$, what's $x$?
Ann
yeah, 5/2.
in the same vein, $\log_9(27) = \log_{3^2}(3^3)$, so what's that equal to
Ann
we cant use the calculator is there a way to do it without a calculator?
So I have explain how to do it without a calculator but briefly. Have you read my post?
yes i read it i kind of dont get it
3/2 i think
yes
alr do i make it into 3/2 log 3 3
ℝamonov
oh okay
as (3^2)^(3/2) = 3^3
bringing it back to the original question i just replace log 9 (27) with 3/2
so i can basically apply this technique to the other stuff
ℝamonov
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The perimeter of an isoceles right triangle is 20. Show that its area can be written as a + b sqrt (2), where a and b are integers to be determined
so i assumed it was a right-angled isoceles triangle
and the hypotenuse was y
2x + y = 20
2x^2 = y^2
x^2 = y^2/2
x = y sqrt(2)/2
idk how to do from there
sub it back into 2x+y=20?
Do you know what would the area be in terms of x and y?
It would be x^2/2, wouldn't it?
So maybe divide both sides by 4, to get x^2/2 = y^2/4
Just x^2/2, lemme draw a diagram...
I think its x^2/2 my Windows keep casting so I cant draw a diagram :/
it has to be written as a + b sqrt (2) 😢
yep
^
After you do this, try expressing y using 2x+y=20
x^2/2 = y^2/4 so 2x^2 = y^2
y = sqrt(2x^2)
Or just use this to find X and y and then find the area
So y = sqrt(2)x
yes
You know: y=sqrt(2)x and 2x+y=20
Now by substitution 2x+sqrt(2)x=20
Can you solve for x?
uh i'll try
This is oné equation with oné variable
You dost need anyrhing else
Hint: try factoring out x
im bad at algebra 😭
x(2 + sqrt(2) = 20
so x = 20/2 + sqrt(2)
so now i need to solve for x^2/2
yeah, just with parenthesis, $x=\frac{20}{2+\sqrt{2}}$
methisalwaysright
so just square both sides and then divide by 2
x^2 = 400/(6 + 4 sqrt(2) if i'm not wrong
dividing by 2, $\frac{x^{2}}{2}=\frac{200}{6+4\sqrt{2}}$
methisalwaysright
Great, so multiply numerator and denominator by conjugate of 6+4sqrt(2)
do you know how to do that?
is the conjugate 4sqrt(2) - 6?
Yes, this would work too
common convention would be writting the conjugate as 6-4sqrt(2), but it doesnt really matter
800sqrt(2) - 1200/4 ?
did i multiply wrongly
$\frac{200\left(4\sqrt{2}-6\right)}{\left(6+4\sqrt{2}\right)\left(4\sqrt{2}-6\right)}=\frac{800\sqrt{2}-1200}{32-36}$
methisalwaysright
i understand where i went wrong
so $\frac{1200-800\sqrt{2}}{4}$
methisalwaysright
just simplify this
Which is something around 17.157
That's x^2/2, which is the area
tysm
So you proved that the area can be written as a + bsqrt(2) where a=300 and b=-200
how do i close this or smth
wait don't close yet, gimme a sec
okay, you can close this now
.close
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yeah gonna need help for this one
@royal basin
repost the problem
yes
i did 99+ 54= 153 something
then I did 180 minus that
then it worked out to be like 27degrees
Lemme get rough work and show u where im at
you can use sine rule
yes, and the sine law relates two sides and two angles
ye
weird
my example looks diff than my book https://i.imgur.com/jLnvND6.png
much easier
that literally is sine rule
okay ty i will try to work on it
just in this case u gotta find the angle opposite to the 8cm
which u did
then use that for sine rule
ye
u dont even have the length of side c
but even if you did have both since its equal it wouldnt matter
im so confused arnt u sppose to label ur triangle?
yeah
like if i get a question like this
whats A and whats B?
isnt the left side C?
that unknown corner
it doesnt matter
you can consider that yourself , use any variable to do so according to me
but the opposite should be the same letter just has to be capitalized
i can label anything I want A B C any point?
see how the angle and its opposite side have the same letter
just lower and upper case
yes
those can be anywhere?
okay ty
the small letters yes I get that
those are opposite to angles
yep
just as long as you understand
that the label is the angle itself
anyway back to the question
so here
oh my days i didnt see the C on the left side
youd use b and c
so using the sine rule, whats ur equation?
okay
so assuming u use my labels
youll use a and c
since you have angles A and C and have side a
you have angle A though
your equation is right
i must be blind
oh im using A and C
yeah
okay
8sin54 over x sin A
but angle A is pointed towards 8cm
yeah ur meant to use that angle
oh x over sin54
actually idk
im just gonna get marks on cosine
and forget about sin
.close
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First one
,rccw
Isn't the sum -b/a?
tanAtanB=-1
yes yes mb
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any one can help me
What
it might help to substitute the definition of f into the definition of g and simplify
@solid harness Has your question been resolved?
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Someone explain how to solve this pls
X^3-x^2<0
< or ≤?
Do I need Ruffini for this
It doesn’t matter cuz I checked and by doing both I don’t get the answer
Do I need Ruffini?
what's ruffini
oh we usually call that synthetic division (for some reason...)
I can't really read your sign table
you have the right roots
The sign table is wrong I tried
I don’t know what to do
your equation factors as x^2 (x - 1) right?
Ye
Sorry I don’t know what a root is, I study math in Italian could u pls show me
just a sec
Ty
where the y value is 0
Ok but how do I solve the inequality
What does the double root mean in the sign table
means that y=x^2 is always either positive or 0
So in the sign table I just put +++
yeah on the top row
Instead of +—
Ok
Ty
But if the exponent is 3
For example
What do I do
Do I put +—?
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Hello. I am a bit stumped by this question. I have no idea how I’m supposed to find roots of these partial derivatives for q9 in my textbook which is asking for the critical points and what is their nature I.e max or min or saddle and what is the value of D.
I have no idea how to pull roots from equations like this. I want to say do simultaneous eqns but I’m like that might be wrong and just complicate it further
Never solved for roots like this before with an eqn like this with a xy term together
After differentiating I mean
I don’t want to keep going encase I keep messing it up further
well in the first equation find x
then replace in the second
surds tho
if u dont want them then try something else
That was my first thought but we have a problem of 1/y in the eqn
If you try and pull factors n stuff to try and get rid of the xy term
For the x derivative
Well divide by y in this case
I’ve done this but I’m not sure this is correct
This is the Fx eqn btw I’m playing around with. Like I’m just unsure about this.
And that did not work
Hang on
Simultaneous eqns does work
Lemme see if this works
It does work
Thank you though.
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If (-2,3) lies on the terminal side of an angle theta whose vertex is at the origin and inital side is along the positive x-axis, then costheta = ?
answer should be in fraction form as well
i tried to solve for an angle in a 2 3 sqrt 13 angle
and then subtract 180 from that angle
and then take cos of that
but the answer is not a fraction
You were on the right track initially. cos(180-theta) is known, i.e. base/hyp = 2/root(13). After that, you can find cos theta. 2/root(13) is a fraction, because fraction doesn't necessarily need to be rational, its an ambiguous term
after getting -2/sqrt13 as cos of 180-theta, what should i do?
2/sqrt 13 is cos(180-theta), don't get confused by the negative x axis, you only consider length in ratio
No worries
What do you think cos(180-theta) should be, its straight forward if you understand the unit circle
yes
ty
wlcm
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what is the derivative of f(H*G) with respect to x in H where H,G are both tensors and * denotes convolution?
i gave the chain rule an attempt but
d/dx f(H*G) = f'(H*G) d/dx H*G
what goes between f'(H*G) and d/dx H*G? it cant be scalar multiplication they're both tensors
f is a function that takes a tensor and returns a tensor
@mental cosmos Has your question been resolved?
Would it also be convolution?
I dont know tensor calculus but if the chain rule extends nicely to it then the * operation should be preserved
Wish i could help otherwise
im really not sure :/
if it was convolution it would just become a dot product with one of them flipped 🤔
cuz f'(H*G) and H*G have the same dimensions
Well if * is the "equivalent of multiplication" for these tensors that would be my first guess
@mental cosmos i looked up the definitions a little and it seems im way out of my league offering advice xD
Hope you get someone that can help
all good, thanks 😄
@mental cosmos Has your question been resolved?
not so sure about that, if you think about the 1D case, f takes a vector and gets out a vector, f' would be the jacobian matrix
i define f myself
its an activation function basically
only changes the values of the input tensor
I mean you said it takes a tensor and outputs a tensor
I just took a special case of that to show that your logic doesn't hold
yeah my comment still stands
wdym
this one?
yes
f and f' shouldnt change the dimensionality
atleast in my use cases
f could be sigmoid for example
sigmoid applied to each entry in the tensor
f' is sigmoid's derivative applied to each entry in the tensor
you should have said that you apply your f element-wise earlier :/
sorry, im not very familiar with tensors, i didnt know there could be cases where f doesnt?
even then, if we're being strict about it, the derivative of a function R^n -> R^n is still a matrix
u mean if f was some sort of linear transformation or something?
in your case most entries will be 0 though yes (the non-diagonal ones)
i didnt think about that
just some function R^n -> R^n, doesn't have to be linear
so is there a way to apply the chain rule to f(H*G)?
been looking for a few hours didnt find anything
i can provide my work so far
i mean i was stuck at that part
but i dont think my notation is good lol
yeah, if we stay on the 1D case for simplicity, let's say n is the simension of H*G, f'(H*G) is a nxn matrix (with a bunch on zeros true), d/dx H*G is a n-dim vector
if we do the matrix product f'(H*G) * d/dx H*G, we get the composite derivative we want (it's like using the multivariable chain rule a bunch of times)
now I'm not saying this is efficient or anything, that's just what we get when we stay on the laid-out multivar calculus path
im not sure why f'(H*G) would be a matrix
f' applied to a 1d tensor would produce a 1d tensor
i know, im only considering the math, not optimiziation, not yet
the usual defn of derivative of a vector input, vector output function is that it's the matrix of partial derivatives of all the outputs wrt to all the inputs
it is true that most entries would be 0 cause you apply the same function element-wise, so you could consider it as pretty much a "1d tensor", but you're already optimizing your computation then
In vector calculus, the Jacobian matrix (, ) of a vector-valued function of several variables is the matrix of all its first-order partial derivatives. When this matrix is square, that is, when the function takes the same number of variables as input as the number of vector components of its output, its determinant is referred to as the Jacobian...
this is like the generalization of the gradient when you have multiple outputs to your function
idk prolly some kind of "higher-order" matrix-vector product
i thought that was convolution, lol
or cross correlation
not sure
cuz convolution can be considered a matrix multiplication in the 2d case
idk a lot about tensors tbf, just wanted to work a special case to see what we could learn from that (and maybe generalize)
that's not even a mouthful, that's a complete bucket of stuff
why are you trying to do that by hand ? just wondering
like I've done that kind of backprop computation for more modest networks
but doing it for a convnet, that's brave
hmmm dunno seemed like the appropriate way to do it
might try another approach tho
every blog seems to just convert convolution into nested sums
probs gonna do just that
yeah I'm not saying it's a wrong approach, it's just gonna be hard to do by hand I guess
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Hi, I keep getting this problem wrong and I have no idea where I am messing up, can anyone take a look?
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i dont even have any work to put here i been looking at this for like 10 minutes but i got no clue where to start
Does you recall the definition for basis?
set of linearly independent vectors that span a vector space
I will assume you know vector space and span definitions as well then
yeah i do
cool
So you need x to be a vector such that, for any vector that exists in U, it can be written as a linear combination of the three vectors in your basis.
Any guesses on how to start here?
not really
im not entirely sure how to use the span that they gave me in the problem; ig i could write out 4 equations with the coefficients id be using for each vector from it?
That sounds like a good start yeah.
You may need just 3. Been a while since I did this, so I could be wrong there.
like
-3a - b - 8c = 0
8a + 6c = 0
-3a + 2b + c = 0
2a - b - 5c = 0
maybe i solve this and determine the coefficents' relationships to each other?
That's definitely one way I believe. You can create your own basis that way, and then maybe transform it into the basis that the answer wants, but that may take some extra work.
do you have another way in mind
I'm working through it right now to see if it works.
In the meantime, here's a free <@&286206848099549185> ping while I work on it.
ty
@strong python Has your question been resolved?
youre still working on it right?
i solved for a b and c and all i found was the trivial solution which doesnt really help me i think
Its a change of basis type of problem i think
Its been a long time since i did something like this but if you review your notes or book look for change of basis
i will
Im sure you'll find an example like this if you have notes
im looking in my book and this is actually a couple sections ahead lmao (ty prof) so i dont have any notes but i can read up on it
this actually doesnt seem like that
change of basis assumes i already have both bases
Yeah this is wrong. All the bases of a vector space have the same number of elements which is the same as the dimension of the vector space
Yeah it's been forever
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Let x,y,z sastify the thing you can see on the first line. Don't care about part a because I just solve it. Find the minimum value of P (in part b)
x,y,z is real positive numbers
@pure glen Has your question been resolved?
<@&286206848099549185> , @left basalt
oh sorry got distracted
first thing you wanted to do is look at 2P
like ive said before
this will get you $P=\frac{2x+2}{2x+1}+\frac{2y+2}{2y+1}+\frac{4z+6}{4z+2}$
garlicbredfries
so then you can simplify the fractions a little bit by changing the improper fractions to mixed fractions
@pure glen
👍
ok, so what do you have now?
this should be 2P by the way, my mistake
you were close, there was just a 6 in the numerator of the last term
$2P=\frac{1}{2x+1}+\frac{1}{2y+1}+\frac{4}{4z+2}+3$
mendeleevpro
now another thing you can do is the z term has a common factor 2
so you can clean it up a little bit more
$2P=\frac{1}{2x+1}+\frac{1}{2y+1}+\frac{2}{2z+1}+3$
mendeleevpro
ok, now im gonna divide everything by 2
$P=\frac{\frac{1}{2x+1}+\frac{1}{2y+1}}{2}+\frac{1}{2z+1}+\frac 32$
garlicbredfries
i want you to use am-gm on the big fraction
$P\geq\sqrt{\frac{1}{2x+1}+\frac{1}{2y+1}}+\frac{1}{2z+1}+\frac 3 2$
mendeleevpro
not quite
hmmm ...
remember, its (a+b)/2 >= sqrt(a*b)
mendeleevpro
$P\geq\sqrt{\frac{1}{(2x+1)(2y+1)}+\frac{1}{2z+1}+\frac 3 2$
mendeleevpro
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
it sucks
$P\geq\sqrt{\frac{1}{(2x+1)(2y+1)}}+\frac{1}{2z+1}+\frac 3 2$
garlicbredfries
there you go
im going to simplify the square root a little bit
$P\geq\frac{1}{\sqrt{(2x+1)(2y+1)}}+\frac{1}{2z+1}+\frac 3 2$
garlicbredfries
do those first terms look familiar
yes
so that means?
P >= 2/3 + 3/2
indeed
so P >= 13/6
ye
we have to find the condition for P = 13/6 can happen
@wooden cipher ?
oh we have to do that too?
uhh by observation x=y=z=1 works
but i dont know how to rigorously prove that
,w solve (x+1)/(2x+1)+(y+1)/(2y+1)+(2z+3)/(4z+2) = 13/6 and sqrt(1+4xy+2x+2y)+2z=5
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,w solve for x,y,z if (x+1)/(2x+1)+(y+1)/(2y+1)+(2z+3)/(4z+2) = 13/6 and sqrt(1+4xy+2x+2y)+2z=5
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I guess P = 13/6 when 1/(2x+1) = 1/(2y+1) <=> x=y and 1/(2y+1) + 1/(2z+1) = 2/3
@wooden cipher
another thing you can do with x=y is plug it back into the original equation
then you later find out y+z=2
so i guess you can do the substitution y=2-z
then solve for y
cool
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Hi! Is this channel available?
Yep
No I'm stealing it... Jk
I have an exercise from the Schaum's of Calculus, it is about finding area under a curve, it is a case that our teachers have not explained to us, and I've been trying to solve it but i don't think i have all the knowledges that it need to solve it. I found the area of the circular sector using that formula, but I don't know how to find the area by integrals. I'll send a picture now of the exercise as it is solved in the book and another picture of my progress with it, i'm from a Latin-American country so my notes are in spanish but the exercise is in english so you can help me, i hope🥲
did you send the picture? :)
Okay, so let me give you a visualization.
So, we want to find the smaller area of the circle.
Now, we want to decide between intergrating along the X or Y axis. For this, we'll choose X.
I do see that you constructed your integral, and it seems almost correct: you might want to watch out that the integral only computes the area of the area above/below the x-axis, not both.
And since the area above and below the x-axis looks pretty much the same (and in theory, it is.) We can just multiply our integral by 2.
Now, let's see the integral we have to work with here.
(I'm using styling common in North America, so it might be different from what you are used to.)
So far so good?