#help-33
1 messages · Page 107 of 1
u waited like a total of one minute
sadly not uncommon
i am an impatient man
valid ig
patience is a virtue i do not possess
and no actually been asking nutka here to expand cos(2x) for approximately 6 minutes
jesus chr7st
XD
what-
i dont know
okay let's go back for a second
okay
you've already figured out that sin^2 2x + cos^2 2x = 1
we know that sin 2x = 14/19
yes
so sin^2 2x = 196/361
all good so far
after that we get sqrt 165 / 19 = cos 2x
,calc 361-196
Result:
165
yep
yes
we know that sin^4 x - cos^4 x = 1(sin^2 x - cos^2 x)
what's the expansion of cos 2x?
sin^4x-cos^4x
okay look
hahah
^ can you justify this answer?
I have weird "5" in my hand writing
I understand
wait
?
but it dont have any sense
I cant solve it
i don't know what any of this is
weren't we talking about sin(2x) and cos(2x)?
i don't see either of those in your work
.
first I had sin2x = 14/19,
then => cos2x= v165/19
<=> cos^x - sin^x = v165/19
and I have to solve |sin^x - cos^x|
yes look
answer this. please
its the literal last step
@static quarry help me out here bro
^ this stuff
thanks bungo
you have established that $\sin(2x) = 14/19$
Bungo
then you used $\sin^2(2x) + \cos^2(2x) = 1$ to get $\cos^2(2x) = 1 - 14^2/19^2 = 165/19^2$
Bungo
so far correct?
I think this is the answer
well the problem is i have no idea what cos^x means
^
and your v165 apparently means square root of 165
this is hard to read
that's why i want to typeset it
and |-v165/19|
i think you probably did the right thing you're just not expressing it in a legible way
yea sorry
Its easier to write that and I ussualy using that way to write
okay so I uderstand it
thank you so much
i get it
but if you want people to help you have to make a bit of effort to make it more readable, learning a bit of tex will take you a long way
okay sorry I thought it is understable
no need to apologize
my handwriting isn't great either haha
i compensate for that by using tex 😆
okay
If you are done with this channel, please mark your problem as solved by typing .close
Can I dont close that, and ask for more help for few minutes?
yea sure
although if it's a new question/doubt, you should just open a new channel for that
okay
helpers are more likely to reply to new channels
cheers
.close
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I to show that v has a potential, and calculate all the potentials of v.
I kniw that i need to do rot=0 but i don’t understand how i can calculate all if the potentials
since you know that the components of the vector are the partial derivatives of the potential function, you can find it by integration. some examples here: https://tutorial.math.lamar.edu/Classes/CalcIII/ConservativeVectorField.aspx
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So I’m confused the work done by a force F WF = |F| * |deltax| * cosa. If a object’s moving down and a force acts down then the work is positive since the direction of displacement and force is the same cos0 = 1. Why is work by gravity negative when Wmg = |mg| |deltay| cos0(since it’s falling and force is also down). So it’s |mg| |deltay| how can that be negative ?
it isnt
work done if the object is displaced downwards due to gravity is positive
if the object was going upwards then work is said to be negative cuz cos180 is -1
That’s what I’m thinking as well
is there any context to this question? like something from ur textbook or smthing
where they took work as negative even though displacement and force is in same direction
The teacher drew some ball that’s falling down and it’s work is mg * (-deltay)
I was confused
Nope its under the influence only of gravity a conservative force
@sterile scroll Has your question been resolved?
Ok all good she’s assuming that we plug in for deltay the negative y since it was displaced down. - - is positive
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what is the question
Prove it
,rotate
apply $tan^{-1}(a) + tan^{-1}(b)$ formula on lhs
{-1}
swerriee
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can someone help me read my teacher's hand writing?
just this part
the inner loop (shaded ?????) has ??? graphed ??? 7pi/6 and11pi/6 set r = 0
help me with the question marks 🙏
maby like the inner loop (shaded margin) has been graphed btw
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this is pretty simple, just split the summation
ren
switch indexes and solve
dang i didnt even think to split them
you shouldn't go splitting things up like this without knowing if they even converge
To make it more rigorous you could put a limit in front
as N goes to infinity
and take the sums from 1 to N

im sorry but im still lost ,how can i find the limit if i dont have an exact function
@helper sorry..
Did your sir not teach you about uniform convergence
The value of the infinite sum if it converges
Is the limit if its partial sums
Do you agree
yes
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can someone quickly help. I am conducting an experiment on transformers to test the efficiency of various materials in the core, I have the input voltage at 10V and a 1:2 coil ratio so i'm expecting 20V, how would i calculate percentage error? Do i calculate how close each value is to 20V, to me that seems wrong since I should be expecting a different voltage for each material since they have varying efficiencies, but at the same time i am expecting 20V due to the coil ratio
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help ive been trying to connect tthem but i cannot find the right sentence and it doesnt sound right, decided to get help
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How to start this one?
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I need to use TFD [series] to state if it diverges or converges
This is what i think i need to do:
arctanx = tan^-1x
= 1/1/tanx
= tan(x)
but im unsure where to go after this
btw this is not correct
arctanx is not 1/tanx
think abt what happens to arctan(n) as n goes to infinity
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ABCD is a parallelogram. m and n are trisecton points of AD. find the ratios of regions, III:I, II:I, and triangle MDC:AMCB
i know the ratio of III:I is 9:1 because similar triangles and areas^2
but if you know how to find II:I or triangle MDC:AMCB plz help because ive been stuck on this question for 5 hrs
<@&286206848099549185>
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@amber viper Has your question been resolved?
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How do i find the volume? is the volume of a right triangular prism (1/2) Base * Height * length?
If so, how do i also find the length?
They give you the lenght
are both legs 6 and 6?
for the triangle sorry
Is my formula correct for the triangular prism?
Yes
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so what is the right solution?
I haven't done inequalities for a long time, I'll have to think
First we know by applying AM-GM inequality (AM ≥ GM) that (a⁴ + b⁴)/2 ≥ √(a⁴b⁴), right?
how can you get a^4?
oh, let me show you the process first
ok
so do u get this
no i dont
oh ya i get, but u got the a^4 by power it right?
wdym by this?
r u indonesian ppl im sorry
i mean like square the equation
idl how can i sa y that in english
What he is saying is right
no, im not, sorry
i dont know bro, im very confusing rn
What you are saying is right @still temple
no, dont worry
do you mind if I take over rq
sorry I don't mean to hijack
sure
no prob
no worries!
okay so basically a good way to solve this question
is to look at the RHS and first come up with a common denominator
we still use AM-GM in my solution
but I think it's a lil more clear
once you find a common denominator and multiply
yes, you should do this
RHS what is that mean
the problem becomes $a^4 + b^4 + c^4 \ge a^2bc + ab^2c + abc^2$
Right hand side
nosqldb
you can simplify rhs further as abc(a+b+c)
yes but I will not bc I want the AM-GM to be clearer
but basically b4 I go
apply AM-GM to two copies of a^4, one copy of b^4 and one copy of c^4
then also apply AM-GM to two copies of b^4, one copy of a^4 and one copy of c^4
two copies of c^4, one copy of b^4 and one copy of a^4
the kinda AM-GM hint is there when u reformulate the q like this
a^4+b^4+c^4/3>...
like that u mean
inthe right side apply GM formula
@boreal rose , do u know how to hide whatever im saying because i want to share the solution with you but in the hidden form
||yes||
the /spoiler
||thank you||
||@boreal rose , here is my solution to this problem: by AM-GM inequality, (a⁴+b⁴)/2 ≥ √(a⁴b⁴)=a²b² so a⁴+b⁴ ≥ 2a²b² , similarly b⁴+c⁴ ≥ 2b²c² and a⁴+c⁴ ≥ 2a²c². adding the inequalities we get 2(a⁴+b⁴+c⁴) ≥ 2(a²b²+b²c²+c²a²) and thus a⁴+b⁴+c⁴ ≥ a²b²+b²c²+c²a². on similar lines if we apply AM-GM inequality again, (a²b²+b²c²)/2 ≥ √(a²b²)(b²c²) and thus a²b²+b²c² ≥ 2b²ac, similarly b²c²+c²a² ≥ 2c²ab and c²a²+a²b² ≥ 2a²bc. Adding these three inequalities again, we get 2(a²b²+b²c²+c²a²) ≥ 2(b²ac+c²ab+a²bc) and thus a²b²+b²c²+c²a² ≥ abc(b+c+a). now since a⁴+b⁴+c⁴ ≥ a²b²+b²c²+c²a² and a²b²+b²c²+c²a² ≥ abc(b+c+a), we must have a⁴+b⁴+c⁴ ≥ abc(b+c+a). Now diving by abc on both sides of the inequality, we have a^3/bc + b^3/ac + c^3/ab ≥ a+b+c hence proving the inequality given a, b and c are positive numbers||
sorry, but im a bit confused. could u explain each line of working?
wait
ok
our way is a bit same
here you proved that both a^4+b^4+c^4 and a^2bc+b^2ac+c^2ab are greater than or equal to (abc)^4/3, but that does not mean that a^4+b^4+c^4 ≥ a^2bc+b^2ac+c^2ab
do u get this solution?
i need time for understand this
but if there is smth i dont understand is it okay if i dm you?
sure, im sorry i wasnt much help to you. im bad at explaining things. but i shared with you what was my solution to your problem
sure, feel free to dm me!
but i think if u could write it in the note
it will be more easier for me to understand
@whole hinge Has your question been resolved?
@whole hinge Has your question been resolved?
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can someone explain me why is 5! needed here
i understand we chose 5 men and 5 womenes and combine them together for every such choice bu using 10C5 12C5
but why 5!
please tag if you answer
may i?
?
Im just trolling

Because the 5 men can be switched around
5! is for the differnt combiantions that can be made
you mean they can have different partners?
Yuh
but can't we use combinations instead
10!/5! * 12! * 7!
sorry permutations
the first one was combinations
Now im just confused, are we not using permutations in the first place?
nope
5p5?
its 10 c 5
anyway acn i do this instead 10!/5! * 12! * 7!?
why are you using permutations
10c5 is 5! ?
is 10!/5!*5!
why do you thinkl this would work
try explaining your reasoning
@proud zealot
becuase it takes care of the order
permutations don't care about the order the cancel the things that repeat
WHAT?
isn't clear what i said?
Permutations does care about the order tho
anyway im confused with the terms
however we have to choose 5 men from 10, here the order of the men doesnt matter
thats why i wanted to do this 10!/5! * 12! * 7!?
could you write it in latex
its pretty confusing
do you mean this
$\frac{10!}{5!} \times 12! \times 7!$
flurry
He does but that looks wrong
yeah the 7! is in the denominator
so when expanding it becomes
$\frac{10!}{5! \times 5!} \times \frac{12!}{7! \times 5!} \times 5!$
flurry
no bro
yes bro
its (10!/5!) * (12!/7!)
what
never mind
He meant 10!/5!
that still isnt correct
this is the answer i get it
my question is why mine is not correct
could you write yours in latex
its very diff to interpret it in text
or just handwrite it and send a picture
i don't know how to use latex
is it that hard to understand this
$\frac{10!}{5! } \times \frac{12!}{7!}$
add a $
lordi
there should be another 5! in either the denominator of 10! or 12!
thats wha i don't get
ok thank you very much
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How do I answer this
@desert prairie Has your question been resolved?
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"a )For what values of the constant k form the vectors a base for R^4?"
how does he breakout k from the matrix here?
This is just using the definition of a determinant
This is a really good video going over the concept of a determinant
While this one shows you how to compute it
The idea is that for a set of vectors to form a basis, it must have a nonzero determinant. So by finding which values of k give you a zero determinant, you can deduce that the remaining values will form a basis
The determinant measures how much volumes change during a transformation.
Help fund future projects: https://www.patreon.com/3blue1brown
An equally valuable form of support is to simply share some of the videos.
Home page: https://www.3blue1brown.com/
Full series: http://3b1b.co/eola
Future series like this are funded by the community, throug...
When it comes to matrices, beyond addition, subtraction, and multiplication, we have to learn how to evaluate something called a determinant. This is a new concept that only applies to square matrices, so let's learn what it means and how to do it!
Watch the whole Mathematics playlist: http://bit.ly/ProfDaveMath
Classical Physics Tutorials: ht...
hmm okay!
You can see also in the thumbnail of Professor Dave's video how he is "breaking out" one of the values. This is how your problem is doing it, but for k
I'm glad 🙂
but why does he take this here can´t i just do k | 0 2 0, K 3 2, 1 1 1 |?
You have quite a bit of freedom in choosing how you compute the determinant. The way that it is written is easiest IMO since a lot of the ocmputation is multiplied by 0. You could do it that way and get the same answer, but the computation will be a bit more hairy
oh okay i am not sure how to do it the way he does
but what do i do know that i have -K |0 2 0, K 3 2, 1 1 1| + 3 |0 K 0, K 3 2, 1 1 1| - 1| 0 K 2, K 3 3, 1 1 1|?
Now you take the 3x3 matrices and repeat the algorithm to get 2x2 matrices. The algorithm is recursive, and each step reduces the matrix down. Follow along with the professor Dave video. It might be easier to start practicing determinants on a smaller matrix
ohh i see! yes okay i will
i dont quite understand what he does in the last step here
Ahh yes, so we \textit{define} the derivative of a 2x2 matrix as follows
$$
\begin{vmatrix}
a & b\
c & d
\end{vmatrix} = ad - bc
$$
So once you get to that step, you just use the definition of a 2x2 determinant to evaluate
curry
that.... that is a good question
hold on, let me check to make sure there isn't a mistake in that
Ohhh I see what they did
They combined a few simplification steps together
I'll explain in just a sec
yes okay!
wait ...... so I'm not too sure how they did that step either. I'm going to assume that there was a mistake, and the missing parenthesis suggests to me that they were being a bit sloppy. I think for you, what is best is to ignore that last step and chalk it up to them making a mistake
yes okay i agree!
yeah Looks like it was a rush job and the professor messed up the algebra a little. The determinant is still correct, however.
yes he has done that a few times before also
okay i will try to calculate it and see if i get the same answer
Free Pre-Algebra, Algebra, Trigonometry, Calculus, Geometry, Statistics and Chemistry calculators step-by-step
But careful not to 100% rely on it as it does things slightly differently than you may have learned.
yes okay i won´t, thank you!
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Derivative
its in a textbook chapter on combinatorics (chapter on permutations and combinations)
yeah that makes sense
So I'm thinking something like this
$$
\sum_{k=1}^n \frac{k}{(k+1)!} = \frac{1}{(n+1)!}\sum_{k=1}^n \frac{k(n + 1)!}{(k+1)!}
$$
krotkin
here
i think
since
its from combinatorics
you should try
turning it
into a sum of binomial
coefficients
$\binom{n}{k} = \dfrac{n!}{k!(n-k)!}$
yes
this form
try to get it into this form
Derivative
the general term of the summation
then it can get easier as you can do alot things
once you have the operator nCr
in the summation
ok
let me try
welll thats what ive been trying to do for the past few days 🤣
uh
Derivative
im trying to get it in the form $\binom{n}{k+1}$
Derivative
so which means
$\sum_{k=1}^n \dfrac{n!(n-(k+1))!}{n!(k+1)!(n-(k+1))!}$
Derivative
now:
$\dfrac{1}{n!} \sum \binom{n}{k+1} \cdot \dfrac{1}{(n-k-1)!}$
Derivative
but now i dont know what to do
There’s an easier way
what if you just had sigma 1/n!
Note that $n=(n+1)-1$
Civil Service Pigeon
From here, ||the series telescopes||
yup
you know whats funny, the moment i looked at this a few days ago, i said telescoping series 🤣
lmao
i just didnt know what to do
just down write down the terms
Oh I didn’t notice that mb
they cancel
I just saw the barrage of Texit lol
I’ll leave you to it 👋
so i manipulate k?
write k as
(k+1) - 1
now simplify
the expression in the summation
\sum $\dfrac{k+1-1}{(k+1)!}$
Before simplifying u need go rewrite denominator
Derivative
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
yes
As (k+1) * k!
now
simplify
ok let me see
finally i get
$\sum_{k=1}^n \dfrac{1}{k!} - \dfrac{1}{(k+1)k!}$
Derivative
and yes this is telescoping
but, why is this problem in a combinatorics chapter?????
so weird
cause maybe you can turn it into a sum of
binomial coefficients
then solve it using combinatorics
( which i won't recommend you can do it with simple summation or differentiation or integration if some constants are multiplied with the binomial coefficients
yes but i think i should learn it the combinatorics way
so i have the above equation
its telescoping, yes.
but can i convert telescoping into a sum of binomial coefficients?
no
idk
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if two planes have two points in common, then their intersection is a straight line
no, not really
The two place can stick to each other
Their intersection would be a plane under that circumstance
yes
which would be a straight line
That happens when the two plane are separated
also in the book it is written that if it is in more dimensions (space) the intersection could only become a point. But I can't understand how
I wrote it wrong, they were two separate plans
if two distinct planes have a point in common, then their intersection is a straight line
if I considered 3 planes their intersection could be a point
This is from this tutorial https://understandinglinearalgebra.org/sec-expect.html
Three lines, and no common point that is common to all three
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Hello
Can someone explain to me what is arccos and how it works?
Asking because i'm using this formula: $arccos(deltaZ / hypotenuse) * (frac{180 / pi})$ to calculate the Pitch angle..
Cut
Its the Inverse function of the cosine
yea
just like e and ln are inverses
The thing is, i don't know anything about it, my school isn't teaching it, none of my teachers know this
I'm studying all alone, so all this is new to me
its like division and multiplication these are also inverse operations for non zero numbers
arccos takes the ratio from a supposed right triangle and finds the angle that makes that ratio
What is this ratio?
so let's say cos(θ) = R. Then arccos(R) = θ, or some angle within its proper domain that kicks out
adjacent/hypotenuse
cos
so arc(whatever) is like inverse(whatever)
arcsin is inverse sin
arccos is inverse cos
etc
Is what i said correct?
Well do you even know what sine, cosine, and tangent do
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: https://www.khanacademy.org/math/geometry-home/right-triangles-topic/intro-to-the-trig-ratios-geo/v/basic-trigonometry
Introduction to trigonometry
Practice this lesson yourself on KhanAcademy.org right now:
https://www.khanacademy.org/math/trigonome...
no idea
Okay
Can it be like
Go to the right too?
Ay, @nova totem, thank you very much for the video
May i save your DM so we can chat sometimes?
I think so, but this is how the unit circle is usually oriented
Okay thanks
Yeah, thanks !
THIS IS SOO GOOD
Thanks
You are welcome!
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any suggestions
on how i can approach this
i was thinking of using bayes thereom
but im not quite sure on how
@cursive jolt Has your question been resolved?
😢
Bayes theorem will probably be useful here. Have you drawn a probability tree yet?
Actually, you can substitute from the word problem itself
In Bayes' theoerm, based on the probelm, what is A and what is B
A could be the result being positive
and B could the aliens having bleep blop condition
Read the question again, what is the probability that you are asked to find?
the probability that the alien has Bleep Bloop given that the test result is positive?
this is how i denoted my p's thus far
then i believe P(Bleep) would be 1/5
(the probability that an alien has Bleep Bloop)
P(Zp) would be 2/3 i think
Yeah, so A would be probability of bleep bloop and B conditioned probability of being positive
I agree yeah
Oh switched, Yea makes sense
What might be tricky here is finding the denominator
do you know what P(B) stands for in the equation you shared?
the probability that the test result is positive
i think
the probabilities for the two conditions (Bleep Bloop and not Bleep Bloop)
yeah the total probability of having a positive test
You will have to find this based on wether the alien has had a ZAP or a ZOP
and the numerator?
P(P|B) (P(B)
would that just be
multiplied by P(B) which is 1/5
P(bleep bloop|positive)P(positive)
right
@cursive jolt Has your question been resolved?
for P(P)
which is the probablity the test is positive
how would you approach this
I haven't reread the question but were you given P(positive |bleep) or were you given P(positive|bleep, zap) and P(positive|bleep, zop)?
if it's the former then yeah, if it's the latter you need to go down each branch of the probability tree to get the total probability
P(positive) @cursive jolt
your approach is correct, just check to use what you are given 👍
thanks
this is what i ended up cooking
sort of just found each part of bayes thereom
and put it all together
Your approach looks right, i didn't check the number but symbolically it looks correct
you found the marginal of probability of positive which is the long part
and yeah you put it together
@cursive jolt Has your question been resolved?
@cursive jolt Has your question been resolved?
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I want to know about area under a graph by double integration
We do double integration by limits of x and y of a function f(x,y) in 3d to find out the volume between the graph and the limits of x and y right?
For area of a surface we use
dydx straight double integration and limits of surface we use f(x,y)=1 so it is a z=1 plane and we calculating volume between the surface and z=1 plane so why it is equal to its surface area please help
@serene basalt Has your question been resolved?
<@&286206848099549185>
You've seriously misinterpreted the surface area formula
The surface area is the double integral of 1 ds over the surface
You can imagine it as taking the arclength in the x-direction
And then summing all of these arc lengths as you move along the y-direction
The formula here comes from the distance between (x, y, z) and (x + dx, x + dy, x + dz)
Which is approximately sqrt(dx^2 + dy^2 + dz^2)
Take sqrt(dx)^2 = dx out and you get sqrt(1 + (dy/dx)^2 + (dz/dx)^2)) dx
https://math.libretexts.org/Bookshelves/Calculus/Calculus_3e_(Apex)/13%3A_Multiple_Integration/13.05%3A_Surface_Area
There's a better derivation here: it should indeed be dA and not dx
In my textbook let's say we have to calculate area of Circle x^2+y^2=1, I use limit x 0,1 and y -(√1-x^2) , √(1+x^2) and integrate by double integral
Here I say f(x,y) integrand is 1
Oh that's not a surface area then
So basically it is the volume under circle and its image
That's just regular integration with respect to dx dy (or dy dx)
Ya
Nope, the circle is already an area
So you don't have to take the area under a multivariable surface
No like we use double integral we have to integrate some f(x,y) and we have limits of x and y like I have for circle so we get volume between the f(x,y) map and circle
There's absolutely no volume in a circle
So here f(x,y)=1
No we are in 3d because z=f(x,y)
Like volume of 1 height cylinder is same as 1 radius circle surface area
Fair enough, okay so in the formula
The partial derivative of 1 w.r.t x is 0
The partial derivative of 1 w.r.t y is 0
Ok
So we have sqrt(1 + (fx)^2 + (fy)^2) dA = 1 dA
It's literally the same double integral
Okay yeah so that's kind of nice it simplifies down like that
You not getting me
In my question f(x,y)=1 so it's a surface z=1, in 3d and by double integration we get volume of a cylinder which is 1 height,1 radius and its same as surface area of circle
Yes I understand you now
If you take the area under that 3D surface, the integral becomes the same as if you use regular double integration
Ya
I not read it anywhere is it true
If again we take a sqaure like length 2 and width 2 so double integral taking f(x,y) =1,is give us a cuboid of height 1 ,now the volume of cuboid is 4, and surface area of square is 4 ,my mind is blown right now
It is like we increase the height of any surface by 1 and calculate volume it is same as curves surface area
@amber birch
Yeah that's what the formula tells you, it's the same if your surface is a constant
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npnp
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What have you tried
What do you mean by "I have tried to just do the root"
You have to look at what happens when you differentiate x^2+1
You get 2x
ye already... oh
so I need to do by subtitution and the i will get it?
Yes
wait but that would be a chain derivative
I was trying to tell you what substitution you have to make
And in order to see that, differentiate x^2+1
u=x^2+1
du=2xdx
or
$u=\sqrt{x^2+1}$
$du=\frac{x}{\sqrt{x^2+1}}dx$
So the integral becomes,
$\int 1 du$
$u+C$
$\sqrt{x^2+1}+C$
The Prophet Of The Damned
wait why 1?
the derivative I already did it
but never understood why the 1?
oh
thx
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how do i find the sum of this series? i just dont know what to do with (-1)^k, if we wouldnt have had it, it would be just geometric series which is easy to calculate
((-1)^k\left(\frac{1}{2}\right)^k = \left(\frac{-1}{2}\right)^k)
maximo¹
He is not the one with the question
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Hi, just wondering does anybody know how to do question 5(a)?
You can substitute the values of x given, you will get two linear equations
Ok
So for f(2) for example, since f(x) = mx + c
f(2) = 2m + c
And it's given that f(2) = 7
Therefore
2m + c = 7
Ya
Similarly do for f(4) and solve the two equations
Yes, that is correct so far
Ok
So while solving a linear equation with two variables, we try to eliminate one of them.
So that we can get the value of one variable, and then with that we get the other one
So you can subtract the two equations
I will send a picture, I don't know latex to type it in discord
Ok
I got it
I think so
Ya
I got it
M=-4
Now i need to find c
C=15
I got it already
Thank you soo much ya!
Uhh sorry, I don't know how to do that question either
Maybe another helper can help
Glad to help
Maybe I'll ask my school teacher
Okay
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hello
yo so i need some of my work to be checked
i’ll send the work when someone is online cuz i have a feeling most of these are wrong tbh
so lmk when ur online
<@&286206848099549185>
i’ll just send it afchalky
for question 4 would the domain be (-infinity,infinity) and the range (4, infinity), the vertex (-2,4), and the axis of symmetry x=2, and the function increased on the right and decreasing on the left
also would it be as y increases x increases when x < -2
i’ll just post this for now and then when someone responds i’ll post the rest
Everything seems right except the axis of symmetry
@rocky lava Has your question been resolved?
oh shoot sorry for the late reply
r u still there
and also what’s wrong with it
wait
sorry i meant x=4
@past frigate
idk why i typed 2
this is true also right?
4?
is this true tho?
oh right
Another(better) way to say that would be that y decreases in (-inf,-2)
Yeah
aight ima send the best question
*next
for 8, i put the vertex is the same and the axis of symmetry is the same also, and the transformation is vertical compression by a factor of 0.75
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✅
ok look up here to see it
The same as what again?
both graphs have the same vertex and axis of symmetry
vertex is (0,0) and the axis of symmetry is x=0
y=x² and y=0.75x² you mean?
and then i think it’s vertical compression
yes
One sec
Ok yeah that's right too
Coz 0.75 lies between 0 and 1

ok so for 12 i got the axis of symmetry and vertex to be the same, and it is a vertical compression by -2/3 and reflection in the x axis
👍
14 i got the axis of symmetry and vertex to be the same again, and it’s. a horizontal stretch by -4
It would be -4 if the function would be -4x²
In this case it's (-4x)²
See the difference?
What is (-4x)²
i forgot to say this is by -2/3 also
16x
16x²**
It's similar to the last few so I'm sure you'll be able to answer this on your own
oh would it be compression then
No it'll be a stretch itself, you're right
oh
I said similar coz
In the last few we multiplied with a constant too
yea
In a, do you think it's a vertical stretch or compression?
compression
oh yea true