#help-28
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The given adjoining solid object is formed with the combination of a pyramid and a square-based prism where the slant height of the pyramid is 13 cm and the length of the side of the prism is 10 cm. If the volume of the solid object is 900 cubic cm, find the height of the prism.
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From point A to plane a, an oblique line AB is drawn. Find the projection of this oblique line onto plane a, if AB = 26 cm, and point A is located 10 cm away from this plane
I drew this, but I don't know how to continue(
How do you get the distance from a point to a plane?
You draw a perpendicular line from the point to the plane, right?
i dont know 😭
So you do know)
If its a perpendicular line then what is the angle formed by it and any line IN the plane?
You can imagine a stick that is held perpendicular to the floor
What would be that angle then?
90 degrees
90?
Exactly
So AC is the given distance of A from the plane
AB is given too
Do you know what is the projection of AB to the plane?
no
You draw perpendicular lines to the plane from the endpoints of AB to get the projection
So whats the projection of AB?
The projection is the line that connects the points where these perpendicular lines meet the plane
If you dont see it just draw perlendicular lines from the endpoints of AB to the plane and show it here
@ocean linden
look as we have a sqaure base
which means the base of pyramid is the same as the width of the square base
which is 10
we get this
and now can you find the height of this triangle?
hmm
like this?
quite not
oh
like imagine in your mind a tright angle traingle
Nope. Didnt we say that AC is perpendicular to the plane?
with slant height given
And B is on the plane
and the base same as of sqaure
I dont know how is it related to the problem
He doesnt even know what is a projection
to find the height of pyramid
this question is of simple maths
not higher grade
like pyhtagroes theorem
Its exactly pythagorean theorem here
let's uh, try to help instead of being condescending?
@ocean linden do u have the answer
I am literally explaining what a projection is
Waqar is telling something else
i apologise if i was not in same boat as you
There is no need to apologize. If you know a better way to explain, go on
i jsut used pythagoroes theorem
as the question has given that the height of pyramid is 90 degree to the plane of sqaure
which means it divides it in two equal halves in 5 and 5
why is a pyramid being mentioned here...
like this? 😭
use a shadow to explain projection?
I have no idea
nope
Okay look AC is you
we need to find AB reyl
the answer is 24, we all can agree on that at least I think
Your head is A and C is your feet on the ground
yeah 24 is what i got
You are perpendicular to the ground
So if I say draw a perpendicular line from your head to the ground you just draw your body
Your body is AC
and u can find AB by pythagoroes theorem
Yep. We can also agree that pythagorean theorem wont help since we need to explain what is a projection first
yes
So again. Which one is a perpendicular line from A to the plane? @ocean linden
Plane is the foor
A is your head
And you are standing on the floor
this? 😭
A
And your feet?
C
And your body?
AC
Which is perpendicular to the floor right?
AC?
Yes!
AC aint perpendicular
like this?
wrong
ohh
No
ohh
Can you connect A to C?
yes
Show me
And AC is your body right?
yes
So doesnt it mean that the perpendicular line is AC?
Cause your body is perpendicular to the ground
yes
if they understand it's perpendicular, proceed,
the figure doesn't have to be pixel perfect...
Im sure he didnt get it
We agreed that AC is perpendicular and he showed me this
@ocean linden what does perpendicular mean?
could be just bad drawing?
Nope
@ocean linden we got this! Which one is the perpendicular line connecting A to the plane?
this is the same question
Not at all but lets not argue
this?
lines that intersect
Told ya @cyan walrus
No no
Perpendicular lines are the ones that form 90° angle after intersection
reyl you should really check again what all these terms mean
In a nutshell. AC is the perpendicular line that I am asking you about
And the projection of AB is BC
We get ABC triangle where ACB angle is 90°
And use pythagorean theorem to calculate BC
But you need to find out what perpendicular lines are and what projection means
btw Fen
oh, thanks
the diagram provided in the book is this
for the questio and ABC is 90 degree
so how can ABC and ACB be 90
It has nothing to do with this problem
that would mean these two add up to 180
where did you even get that...
it wasn't sent by anyone other than you
Waqar, again, these are two different problems
This was the given task
Suppose you have a random stick AB obliquely on a plane,
to find the projection of the stick,
you shine a light source directly above the point A of the stick.
the shadow will be it's projection.
shining a light source straight above means the shadow will start from a point on the plane straight down from point A, which is C.
since C is straight down from A, they form a 90 degree angle with the plane.
in the figure, the red line is the shadrow or, projection
once you get that much, it's just applying the pythagorean theorem
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@misty lodge
i sincerely apologise
i was looking at this the whole time
Nah all good
still pyhtagroes theorem
Yea we use it in the end
middle school paid off
Heh. All the best mate
Goodbye
@torn jolt Has your question been resolved?
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ask the question
What step are you on?
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2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
hm , ok so , do you know this is called a quadratic equation
do you know the quadratic formula?
and this?
since it's a polynomial of power 2 you can reliably factorize it as two terms, thus (x+a)(x+b)
middle term breaking
think what values of a and b would lead to (x+a)(x+b)=x^2+9x+14
that's x^2+(a+b)x+ab
so a+b=9 and ab=14
type .close
for b part can you tell the type of graph it will form ,
like this is also a quadratic equation
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hello
I am trying to find if this function is differentiable
using alternative derivatife form
my question is when the piecewise function has a function for x = 0, where do I use that?
for example here when finding the limit from the right, instead of f(0) do I input x + 1?
the function is not differentiable at x = 0, because f is not contnues at x = 0,
lack of continuity of a function at a point, it is enough to state the lack of differentiability, because if a function is differentiable, it is continuous,
exactly, should be written 1
Thanks @buoyant pewter @rare dock, btw this is not real exercise its just something i came up with to check if such thing is even possible lol
Also if it was 1 it wouldnt change anything right?
Still not differentiable
if you put, 1, still lack of continutiy
since the left and rgith sided limits are diferent
you need to change form of yoru function
Thanks
yw)
@compact cipher Has your question been resolved?
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For which X does the following makes even sense:
[ x \in X \ , \ k \in \mathbb{Z} \hspace{1cm} x \leq k ]
Tobi
Clearly for
[ X = \mathbb{N \ Z \ Q \ R } ]
But are there others
Tobi
well you can for example set X=some function space and then partially order that
and then f<=k means that f(x) <= k for all x
or you can have something like hyperreals or whatever
True okey , then I have to define myself somthing to make sense, are there like already existing definitions I can use
I mean if you want to use the <= as you are using it right now, then by definition that only works for real numbers
so X some subset of R
so that kinda makes the question pointless
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I know the answer is A
I dont know why
I also know that f is concave up and $f^{'}$ is strictly increasing
Fen
And I know that f(x) decreases from -2 to 0 and increases after that
<@&286206848099549185>
Well guess we aint sleeping this night
Its not even about math anymore. I have a personal beef with this problem
Yes
The derivative is negative
Actually you know that f' is <0 for all x<0, f'>0 for all x>0 and f'=0 in x=0
So you can say that f is strictly decreasing from negative infinity to 0, then in 0 there is a minimun and then it is strictly increasing from 0 to positive infinity
Yeah I think I got that part

<@&286206848099549185> 
.close
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help?
you can call the total number of new at-bats "n"
so you add "n" to the denominator, and a multiple of "n" to the numerator. then solve for "n"
well ik the thing is that its 24+.35x/110+x=.3
right?
yes, so just solve it
why why is .35 on the numerator
? you just showed it yourself
ik the answer but i dont get how
why is .35 on the numerator?
re-read the problem carefully
i am tho
you responded too quickly to have read it carefully
so future at bats will be average of .35
and at bats is denominator
yes
so the denominator is. 35x?
no. the denominator is what you wrote above
denominator is at-bats. numerator is hits
and the problem says for all of her futurare at bats she will have a batting avg of .350
yes
there will be N additional at-bats. 35% of those (0.35N) will be hits. so you add 0.35N to the numerator, and just add N to the denominator
wait how do u know 35% will be hits?
wait thats what batting avg means?
you are given that
which is 35%?
re-read the problem
can u just clarify this one thing? why do we add 24+.35x?
here?
@ember shadow do u have any tips for these types of world problems?
just read them carefully and use what is given to you
bro please
@harsh elk Has your question been resolved?
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yo
I have a calculus problem under the packet “6.5 Behavior of Accumulation Functions”
I am stuck on #’s 3 & 4. If someone could give me detailed instructions for #3 I could try the same combination for #4. Thank you.
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Hi there, I am trying to solve a second order differential equation (non homogeneous and also its an amended particular integral) to find the general solution
I have found so far, GS = Ae5x + Bxe5x + Ce5x, where *C * is a constant.
However after solving the equation, I have found C to be 0. Is this possible?
Where this was the original equation;
So therefore, GS = Ae5x + Bxe5x
?
yeah
Ce^5x is already one of your homogeneous solutions when you think about it
you'd expect it to end up being 0 after plugging it in your DE
so you have to use the same old "multiply by x trick"
https://math.jhu.edu/~brown/courses/f18/ExampleProblems/UndetCoeffBadGuesses.pdf here's a pdf which explains that in more detail
@clever zodiac
@clever zodiac Has your question been resolved?
Ohh, I see where I went wrong!
I forgot to include the x in the working out, meaning I came to 0.
Therefore, I couldn't find the constant for C.
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Help
!status
What step are you on?
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2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
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Where did I go wrong? Apparently there is a simplification where (N / (20-N)) = Ce^(1/4)
You're not wrong but when you e both sides you get $$e^{t} = e^{4 \ln \lvert \frac{N}{20-N} \rvert + C}$$ which using the index laws becomes $$e^t = e^{4 \ln \lvert \frac{N}{20-N} \rvert} \cdot e^C$$ and $e^C$ is itself a constant (another number) which you could probably rename to $A$ so you end up with $$e^t = Ae^{4 \ln \lvert \frac{N}{20-N} \rvert}$$
I can't believe you've done this
if you used your value of C you got you would still end up with the correct answer albeit a bit different because ln(6561) = 4ln(9) (= 8ln3 but 4ln9 is more useful) and when you combine the ln using the logarithm rules you get t = 4 ln (9N/20-N)
@rugged plank Has your question been resolved?
I see. So how would you get (N / (20-N)) = Ce^(1/4) ? Like if you move A to the other side I could see (e^4)(N/(20-N)) = Ae^(1/4) but not (N/(20-N)) by itself
@rugged plank Has your question been resolved?
e^(4ln(N/20-N)) doesn't equal e^4 * e^ln(N/20-N) since theyre multiplied by each other in the power
it's also probably better that before solving for c you make N the subject since imo it makes calculating the final answer a lot easier
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I have gotten 8pi/3 is this right?
Show your work
@calm trail Has your question been resolved?
<@&286206848099549185>
@calm trail Has your question been resolved?
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hi no one answered last time hoe to do part b
<@&286206848099549185> i know it hasnt been 15 mins but my previous attempt to ask was timed out so
It's not easy to read that
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not sure what to do with this
Plug in the solutions
for b and c?
or plug in for x
and solve for b and c
solutions are pi/6 and pi/4
but how would you solve with two unknowns
system of two linear equations you receive, ...
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hello, what is the inverse of the isomorphism of the chinese remainder theorem between Z/aZ et Z/bZ?
$\phi : \mathbb{Z}/ab\mathbb{Z} \longrightarrow \mathbb{Z}/a\mathbb{Z} \times \mathbb{Z}/b\mathbb{Z} \
\quad x \mod ab \longmapsto (x \mod a, x \mod b)$
lilisworld
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what part of this are you struggling with
did you directly plug in 13
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how would i approach this?
are you trying to differentiate it
yes
i assume product rule
yeds
1/y= sin(x) * 5/5x+2 + cos(x) * ln(5x+2)?
you forgot one term
then multiply the orignal function over to the other side
well yeah
which?
you right
you multiply y, the original function, to isolate dy/dx which is your derivative
not plus
would be yeah
thank you
so (5x+2)^(..) * (chain term 1 + chain term 2)
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for part C do I have to consider whether or not the set spans H (I don't think I do) or can I just say whether or not the set of matrices is linearly independent? Additionally, for part D, if the answer just false because the set only has two matrices, but the minimum required to span is 3 since the dim(B) = 3?
For c) you only have to see if the given matrices are in H and linearly independent of each other
For d) I think you are having the right thinking
alternative phrasing: can 2 2x2 matrices form a basis for all upper triangular matrices?
So since the matrices given in the set for part C are upper triangular matrices and since they are linearly independent, can we say that the set is a linearly independent subset of H?
there's two aspects to this, are they in H? clearly
are they linearly independent? if you say so ( i dont care to check)
If both are fulfilled they are a linearly independent subset
the definitions are just legos added to each other
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I think i found a mistake in a problem
Each afternoon Enrico rides the 20km from work to home but one day he got a flat tyre and had to walk the rest of the distance. He rides at an average speed of 30km/h but walks at 6km/h. If the entire journey took one hour, how far did he have to walk
wait brb
@marsh tusk Has your question been resolved?
ok
so basically
i did this:
x/30 + y/6 = 1
x+y=20
and through substitution, i got y=2.5
and since 2.5 is the time
and the question is asking how far
so distance = speed * time
so 6 * 2.5 = 15 as my answer
but in the solutions they just had 2.5 as the answer
am i corret
<@&286206848099549185>
yo
i get 2.5 as answer
30x +6(1−x) = 20
24x + 6 = 20
x = 14/24
6(10/24) = 2.5
x/30 + y/6 = 1 clearly uses y to mean how far
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Z-test with an alpha level of .05
@rough temple Has your question been resolved?
<@&286206848099549185>
.close
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<@&286206848099549185>
how do you do this quesiton?
this is based on poisson's distribution
<@&286206848099549185>
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wrong one.
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f
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@odd bloom Has your question been resolved?
no
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we can start by substituting cosx = (e^ix + e^-ix)/2
right
but then when you sub t = ix (i - iota)
is it possible
because then what is the new upper limit
inifinty times iota 🤔
@ionic path Has your question been resolved?
why are you doing this substitution?
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I don’t understand this at all, he kept doing so much and I just couldn’t understand it
And I thought that X would be half of 49 but it was 10 so idk what to do
wouldn't the angle be the same?
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could someone show me why C isnt the answer? whats an example of a function defined on [0,3] that doesnt have an extreme value??
@ocean urchin Has your question been resolved?
bunch of horizontal lines
like, the last line is "all maxima" but no point is special, they can't all be extremal at the same time
i think it's like that
hm maybe not
yeah i agree with you now
@ocean urchinthis one
not on [0,3], just generally
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when you bring the constant out of a integral do you have to multiply the bounds by the constant?
like if i have
pi/4
| 1/2(cos^2(2x))
-pi/4
I dont multiply the pi/4 by 1/2?
no
idk what im doing wrong in this problem but i keep getting the wrong answer 1 sec
you are still integrating from the same bound
okay thats what i thought
why am i getting pi/16 w instead of pi/8 which is the right answer?
ive done it like 5 times i dont understand where im going wrong ???
oh i forgot ab -pi/4 so when u minus the neg pi/16 + pi/16 = pi/8 ok
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,tex .log rules
riemann
Second row
So we did not need to replace Ln(r) at first
since it cancelled out
or change it to square root form
There are a lot of different ways to simplify
An arguably simpler way is to use the first row in the first line
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If n, m ∈ N\{0}, the number of functions f : {1, 2, ..., n} -> {1, 2, ..., m} that are monotonically increasing is C(m-1, n-1)
is that true? Answer given by Bing AI
or
Nah, doesn't look true to me.
Can you take an example like n = 2, m = 2. Then Bing AI claims that there are C(1,1) = 1 such functions.
chatgpt said using the principle of inclusion/exclusion which sounds ok until I try to use it
and idk how
It's a so-called stars-and-bars problem.
alright, I'll look it up
These chat bots are still horrible at math, I haven't been able to get a right answer out of any of them for any non-trivial problem.
indeed there's only one mapping of 1..2 to 1..2 that's increasing
the question can be reframed as: how many ways are there to map the range 1..n to 1..m
can anyone help
Agreed, but according to the picture below, the term meant is "non-decreasing".
Find the smallest value of N for which we can say: among any N number of numbers, there are 18 numbers such that their sum is divisible by 18
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i see, that is peculiar
but it wouldn't make as much sense anymore, no?
For strictly increasing, it would be C(m,n).
How so?
right, but for >/= what is the answer?
I saw the stars and bars problem and understood it
but how do I apply it to find the number of functions here
It's C(n+m-1, m-1)
if they're nondecreasing, i could just map everything to 1, i don't think any degree of surjectivity is specified
you're right, but could you explain it, please? where does -1 come from?
ik C(stars+bars, bars)
oh wait
bars is m-1
right
but why?
Indeed that is a possible map.
It's like, let there be a star for each number in {1, 2, ..., n}. Perhaps ¤¤¤¤¤¤¤
If I put the first bar somewhere, it means that everything to the left of the first bar is mapped to 1 in {1, 2, ..., m}. The next bar I put, it is everything between the first and second bar that is mapped to 2.
So ¤|¤¤||¤¤¤|¤ corresponds to the map 1 -> 1, {2,3}->2, {4,5,6}->4, 7->5
right, ok
if you guys don't continue your topic
I'll close this
We won't continue.
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I know this is true but I forgot why you put ln there again?
my question is just basically why the answer to the 2nd one is ln3 * 3x
because of the formula. x is an exponent here.
what formula
Have you seen the limit definition of the derivative?
because d/dx = a^x follows the rule ln(a) * a^x
oh I just remembered
thanks
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just to make sure, the answer is c?
@torn jolt Has your question been resolved?
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ρ = {(1, 2),(2, 3),(3, 4),(1, 3),(2, 4),(4, 4),(1, 4)}.
this relation is only transitive right?
which properties are you checking?
it's also antisymmetric
oh because there's 1,3 and 1,4 but nothing to compare them to?
or am i misunderstanding?
what do you mean by 'nothing to compare them to'? there's nothing special about those
yes
now i might be blind but there's (x,y) but there's no (y,x) so it's automatically antisym?
ah
yes
sorry you bringing in specific examples confused me
actually
yes with the one exception of (4,4)
now i'm confused
oh i see your point
nvm me
may i ask you another question? another exercise is unclear to me
go ahead
The relation ρ is defined on the set of N natural numbers
m ρ n ⇔ 3m and 5n give the same remainder when dividing by 7.
Examine whether the relation ρ is reflexive, symmetric, antisymmetric, transitive
so am i to find what m and n is here
you're meant to either find m,n naturals that are counterexamples to the properties
so e.g. if it is irreflexive, find specific n s.t. 3n and 5n have different remainder so not n ρ n
OR show that whatever you're picking, the property holds
i.e. work with completely general m and n
if you can see how to use properties of natural numbers and remainders, you can use those
or you can brute force
(in this example the counterexamples to the properties seem to be small)
what do you mean by this?
just that using things you already know about how remainders work might help you guess which properties hold, or how to find counterexamples
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Does anyone know
@wraith river Has your question been resolved?
It means the graph is lower than 0 at that point.
The underground part.
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i have to graph the antiderivative of this function
doesnt seem right? it appears to me that it should always be negative
wait wdym?
im honestly pretty confused on how to graph this
antiderivative is signed area under the curve
alternatively, you can consider what the derivative of your function should look like
if your answer was right, the slope should be positive from 1 to 2.5, and the original graph definitely isnt positive from 1 to 2.5
like this?
no
it should be decreasing from 0 to 2, increasing from 2 to 3, and decreasing again from 3+
but it definitely never goes positive
you are graphing how much area is under the curve from 0 to that point (not really but its close enough for this)
how come its never positive
theres never a positive amount of area under the curve!
theres always more negative area than positive area
how do you know this?
ohhh
the antiderivative is graphing area under the curve of the original function
but isnt the area from 2-3 positive?
so why did you say the whole thing is negative
do you think theres more positive area between 2 and 3 than negative area between 0 and 2?
I dont think so, so the total area will stay negative
oh
remember total area from 0 to the point
right
in reality its actually total area from some previous point to that point, which means the "starting area" by the time you get to 0 can actually by any amount
im rooting this at 0 for intuition purposes, but the integral graph is allowed to shift up and down freely
so something like this?
yeah thats much closer
what am i missing?
well you drew it by hand so its gonna be a bit off by default, but you can try thinking about how fast area is changing to play around with the slope
i think thats probably in like good enough territory though
derivative is the slope at each point
f' is positive when the slope is positive and negative when the slope is negative
the more positive the slope, the more positive f' is
i see
btw, did we have to take the critical points of f in account for the graph of F?
@left bone
@left bone
?
what
Are u good at trig good sir
critical points are just the zeroes of the derivative
so yeah i guess those would help
but it should like end up coming naturally if you do what i said
so my sketch is innacurate?
im good at everything, but this isnt your channel and im not going to help you here
idk i havent seen your sketch for f'(x)
Wow
That hurt my feelings
Ngl
i was talking about F
oh no critical points dont really matter for F
in fact i think they matter like not at all
ah got it
here is my sketch for f'
wait i messed up
here @left bone
wait no i messed up again
you there?
something like this
yeah looks about right
my lines are straighter, but i suppose its plausable it oculd be a function such that they could be curved
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can any1 help me solve this
(11+n) *400-20n=4760
what does n represent here?
@glad umbra Has your question been resolved?
@glad umbra Has your question been resolved?
N represents the tickets price going up by 1
Its 14$
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how do i find the average daily balance?
Why is balance increasing
my teacher said something about it increasing because on a credit card it charges
something like that
Oh I see
The +55 is correct because of what u said, but the +20 should be -20 because you are paying it back
ohhh i see so that was my only mistake
And the # of days thing
why do i have to add 1?
and for the balance for the july 3-14 the balance stays the same as the july 1-3 right?
@strong apex Has your question been resolved?
how can i tell the difference between simple and compound interest in these word problems
@strong apex Has your question been resolved?
not yet
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Can someone help pls? I’m not sure on how to find x
pythagorean theorem
It’s special right triangles how I do that
do you know trigonometry?
No
Idk it just says to find x
I already have all the stuff for the first triangle I js don’t know what to do for the second
Wait why did u do this
@glossy isle Has your question been resolved?
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Can anyone verify that a few relation proofs are correct/
Just send one at a time
And wait until someone checks one question before asking another
@pliant heron Has your question been resolved?
Okie will do!
Yup for sure got it! wouldn't want to overwhelm anyone : )
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Where did the 2pi come from on the last step
length of interval
How does that appear
It doesn’t look like ML inequality since that has the absolute values on the outside
they are bounding the integral by $\int_0^{2\pi} number dt$ which is equal to length of interval times number
Denascite
where number=the supremum
yes
Then you evaluate the bounds and get the 2pi
yes
Ah
or just geometrically, its a rectangle
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Find the volume of the solid generated under the region when $y=\frac{1}{x^{4}+1}\left{0\le x\le1\right}$ is rotated about the y-axis.
water beam
(do I have to integrate $\frac{1}{x^{4}+1}$ is there no way around this?)
because like
it doesnt look fun
water beam
@twin wolf Has your question been resolved?
$\left| V_{OY} \right|=2\pi\int_{0}^{1}xf\left( x \right)dx=2\pi\int_{0}^{1}\frac{xdx}{x^{4}+1}=\\=2\pi\int_{0}^{1}\frac{\frac{1}{2}dt}{t^{2}+1}=_{\cdots }$
Joanna Angel
so I don't have to integrate 1/x^4 + 1?
write it in your exercise book and continue solvign ti, it is alsmot done
water beam
I forgot the shell method saves this whole thing with the x
it's ok
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continuity question:
let f(x) be some function that is defined this way:
for any x e R \ {-1, 2}:
for x=-1: f(-1) = A
for x=2: f(2) = B
how can I show that continuity holds at the point x=-1 for certain A using epsilon-delta?
I know that I can show lim[x->-1]f(x) = -2 and therefore A must be -2, but I want to show it using epsilon-delta
what I have so far:
$0 < |b- a| < \delta$
tales
For $b\neq a$, we have $f(x) = $ something defined at x = -1
tales
ys
how would you continue from there
,w (x^4 -5x^2+4)/(x^2-x-2)
$f(x) = \dfrac{x^4-5x^2+4}{x^2-x-2} = x^2+x-2$ for $x\neq 1$ and $x\neq 2$
tales
ys
Call $g(x) = x^2+x-2$
tales
g is continuous
yup
I tried applying it here, but from then onwards I don't know how to fetch a delta
what I essentially need to show is that there only exists a delta for A=-2, but I can't yet presume that I know it only exists for A=-2
From continuity of g, applied on x = -1, you have
$\forall \varepsilon \exists \delta ( |x +1| < \delta \implies |g(x) - g(-1)| < \varepsilon )$
tales
ys
I dont wanna do the math, but you should get the same inequality
but how does that prove that A must be -2
or generalised, how does that limit the possible values of A
I'll repaste the question, but thx for the attempt @dusky locust :)
@sacred sparrow Has your question been resolved?
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!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
1
What is "amplitude", "period", and "angular frequency"?
How do I find amplitude, period, and angular frequency? Is there a formula?
What does your math textbook say about that?
amplitude is easy it, is apparently the absolute value of a or the number in from of cos or sin
period is 2π/absolute value of b (which b is the number being multiplied by x or in the case of this problem t)
I think I am fine for the rest of this problem now, thank you!
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STATISTICS
When I am harvesting 2,000 silkworms, I am expected to get 11,000 threads of silk
How do I get the standard deviation for +/- threads from harvesting all the 2,000 silkworms?
info:
Silkworm drops between 1-10 (ONLY INTEGERS) threads and you can assume each value (1, 2, 3..., 10) are equally likely
STATISTICS
Please guys, im trying to find if I have a reasonable suspicion for my worker to have stolen some of the silk threads
Its for hit game Growtopia
Calculating the precise standard deviation most likely would require the use of the multinomial theorem, which would be pretty tedious to have to use
Your best bet would probably be to run a simulation
@foggy shore Has your question been resolved?
Wait, actually? So thats why they always give you the standard deviation in high school statistics problems
I was also surprised how no one else commented anything on this
Well, for some distributions the standard deviation is pretty straightforward to calculate
What you're describing is the sum of 2000 discrete uniformly distributed random variables
