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show work
,rotate
,rotate
leave out no details
that's all fine
how are you going from
$$\br{\frac 34 - \frac92 + 6} - \br{\frac{48}{4} - \frac{36}{2} -12}$$
to your value
ℝam()n()v
how are you simplifying that to get 33/4
@civic geyser Has your question been resolved?
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Hello, A = 23!
In how many different combinations will A be a product of consecutive numbers?
The answer seems to be 3, but how?
23 fact. ?
Yep
what does combination mean here
like 1.2.3....23 and 2.3.4......23
do you think the question lacks something?
the other one seems to be 5.6.7.....24 but how do we determine if these are all
yep
so we'll need to write 23! as the multiplication of consecutive numbers like 2.3....23 and 1.2.3....23
if we take the 1.2.3.4 as 24 in the beginning and add it to the end it will be 5.6.7...23.24
Oh ok
yes so these make 3 combinations, and I'm asking how do we determine there's just 3
intuitively these are the only possible
haha yeah
yes
Otherwise it is less than 23!
I'll go eat real quick brb
ok
so we nneed to prove that 23!=m!/n! has only one solution if m and n are int
oh 24!/4! is 1.2.3. 4.5.../1.2.3.4=5.6.7.8.9...
But it is also
1.2.3.4.5.../1.2.3.4=1.2.3.4.5.../24 = 23!
we remove some largest nums using ONE factorial
Btw i noticed
24!/4!=(4!)!/4!
it is equal to (4!-1)!
Wow
It doesnt help
Nvm
Product of removed numbers from start MUST equal product of removed nums from end
So since we use only one factorial we cant remove things like 24.25(4!.5.5)
That means that with one factorial we can only remove 24 but not 25
YES
My "proof" is a mess but hopefully you can see an idea
@crimson sedge
@crimson sedge Has your question been resolved?
back
exactly
@sudden pivot thank you so much for your help
if I recall correctly someone here tried to solve it with polynomials and derivatives, they were probably chai trex
I will work on what you said aol
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Δ = 18abcd – 4b³d + b²c² – 4ac³ – 27a²d².
wat
What class/year is this?
Depending on that, you could try guessing with remainder/factor theorem.
Do you use factor/remainder theorem
Basically trying in numbers until it works and then factorising the factor out
Yes, but before dividing you try numbers
Well, if you haven't been taught another method, I'd suggest you try that
Can you explain this
I googled it
Do you know how to work with derivatives?
yes
Impose a condition on a such that the cubic must have two extrema, the values of which are of opposite signs
you should find two local max/min points
,w graph x^3+x^2
,w graph x^3+x^2-0.05
do you see how to ensure 3 x-intercepts?
yes
but the equation is x^3+ax^2-1
and we only get min max points
which aint x intercepts
are they in the middle?
yep
the second x intercept must be betweeen the min/max points
how do we use that to solve the problem?
what is it
,w graph 10(x-1)(x-2.5)(x-3)
k
it just have to be between
how do we ensure it pass through x=0 between the min/max points?
this will be easy to understand using the intermediate theorem
whats that
it basically said if you have two points of a function a,f(a) and b,f(b)
there exist point c between a and b such that f(c) is between f(a) and f(b) for any f(c) between f(a) and f(b)
so what would the middle intercept be?
it depend on a
and we just need to make sure middle intercept exist
the middle intercept must be y=0
we want y=0 between two min/max points
let's consider three cases
don't care about a for now
try drawing a cubic graph for the three cases
you'd see how the min/max value affect the middle intercept
ok
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please help with iii
<@&286206848099549185>
@wanton summit Has your question been resolved?
@wanton summit Has your question been resolved?
@wanton summit Has your question been resolved?
Use the fact that in terms of its argument $\theta$, z can be written $e^{i\theta}$.
Enemagneto
Actually don't even need that.
Show then.
perpendicular bisector means theres a right angle
at
at OMA
where M is the midpoint of OC
Why do you wanna do it with geometry ?
its a lot more elegant
It's a cinch with algebra.
ok how do you do it algebriaclally
its asking about the modulus
not the argument
You mean... in general, geometry is lot more elegant than algebra ?
Yeah. I can read. Lol
Many would disagree. Nevertheless, we digress.
really
What's your approach geometrically ?
With algebra, I can do it in my head. 😐
we have proven BOA is theta from b
and a rhombus splits theta in 2 from a diagonal
let M be the midpoint of OC
diagonals bisect perpendicular on a rhombus
so OMA is a right angle
we work out costheta with right angled trig
and multiply by two
for the magnitude of OC
im not sure how to do it algebraically
algebraically thats twice now
Wait... I'm confused. So you have done it geometrically? What's your doubt then?
Just put z = cos(x) + i sin(x), i have replaced theta with x for ease of writing.
In |z+z^2|.
Wdym whats my doubt i already said i’ve done it i just forgot to close the channel
sorry about that
what about the radius
or modulus
Gosh. Lmao.
That just means that you take mod at end.
anyway, your |z| = 1
oh
right yes
how do you arrive at the half angle expansion for cos though
in your head in particular
|z+z^2| = |z| |1+z| = 1 | 1 + cosx + i sinx| = Sqrt(1 + cos^2(x) + 2cos(x) + sin^2(x)|
= sqrt(2(1+cosx))
Now, use that 1+cosx = 2cos^2(x/2)
There's your answer.
Now, i gotta go. Close this after you are done.
.close
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a1! * a2! * ... * an! <= (a1+a2+...+an)! It should be proven by the method of induction, so we have the base for n=1 and it's trivial and it's equal a1! = a1!, and we have a hypothesis that it is correct for n=k, so we should prove it for n=k+1
I think we should probably use the a_k+1 ! member and say, a_k+1! = a_k+1 * a_k * a_k-1 * ... * a2 * a1, and the hypothesis covers the a_k-1 * ... * a2 * a1 part
But I am not sure, it's just an idea
so it's a_k+1 * a_k!
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hi i have a quick question on parametrization
so lets say I have a surface S: x+y^2-z=0
and lets say that $0 \leq x \leq 1$ and $0 \leq y \leq 2$
jriver
and i want to parameterize this in terms of $u$ and $v$, where $x = u$ and $y=v$
jriver
what would my position function $\vec{r}(u,v)$ look like?
jriver
thanks in advance for the help
btw in case i did not phrase this clearly, this problem is from: https://www.khanacademy.org/math/multivariable-calculus/integrating-multivariable-functions/surface-integrals-introduction/v/surface-integral-example-part-1-parameterizing-the-unit-sphere
im just confused on how he created his $\vec{r}$ function
jriver
@bitter wadi Has your question been resolved?
@bitter wadi Has your question been resolved?
rip
Can you post screenshots
Or timestamp
its pretty much what i wrote above but sure
10:02 is timestamp
nvm i get it now
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Hello there, so I am currently learning calculus and am hell bent on the idea of learning the proofs, whilst learning the material as I find it fascinating. Anyways, so I am in the midst of learnign the power rule for the derivative where we have x^n, differentiate it and we have nx^(n-1). Now I know that if I implement the definition of the derivative I will ultimately get the same result as nx^(n-1), after going through some nasty algebra. After this, I noticed another way of proving it which was using the binomial expansion theorem, which I have no knowledge of as my Pre Calculus 12 Course did not cover combinatronics. With this said for learning future calc proofs and calculus will the fact that I don't knwo combinatronics come back to haunt me? Should I learn it now or perhaps later in my own time?
May I speak with you in DMS for a second?
No
May I speak with you in discussion?
Anyone in #discussion can help you
Right, and not discrediting anyone, but I've seen you on this server and you have a great deal of knowledge according to what I've seen, so I would appreciate if you had the time it would be nice, but if not no worries and have a good day or night. Heading to the discussions channel.
No, anyone else can be just as helpful
Alright thanks. Cya.
Just at the very least learn binomial expansion
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the original question is to look at arrays of length 6, and to answer if we have more arrays that the sum of all digits is 27 or that the sum of first three digits is equal to the sum of last three.
the first answer is binomial coefficient 6 + 27 - 1 choose 27. i'm trying to solve the other part now, i tried writing the numbers to try and see some kind of logic but just from 0,0,0 to 1,1,1 we have like 38 combinations or more, maybe i missed some, from (0,0,0),(0,0,1),(0,1,0),(1,0,0) combinations to (9,9,9)
that was my initial idea, and we have to restrict a,b,c,d,e,f to digits from 0 to 9
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7:30 i think
Do you know what the minute hand is?
short line = hour
long line = minute
@hot python Has your question been resolved?
oh no i cant read
let me
so like
3?
1:30
7:30
10:15
10:45
but these are my options
Do you know which way is counter clockwise?
First do you know how to read an analog clock?
Lol
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i am stuck on these ! could someone pls help ?
uh, which question
all of them, idk how to do it
is there something in particular that is confusing you?
why don't you give it a shot and then if you get stuck somewhere come back with your work so we can help you through it
look up a formula for the average rate of change, that first question should be fairly straight forward from there
@crimson sedge Has your question been resolved?
i have, but it didnt rlly gelp idk 😭
i mean you use 2 coordinates to get the rate of change right?
$rate of change: \frac{y_2-y_1}{x_2-x_1}$
Wumbo
then plug the coordinates into this equation to get your rate of change
%
^
or 1/2
would that be it then ?
what are the 2 given points on that graph?
(1,6) and (-1,2)
i think that 6 should be a 5
yes
okay so then what's the average rate of change over the interval [-1, 1]
yesss
oh yayy
okay try the next one
oki
same thing different coordinates
7/3
correct!
the third one is only slightly trickier
but it's the same thing, different coordinates
just mind your signs
should be -2/1 but yes
yes
yes
ohh okay
between that interval
what abt the number 4 question?
so for this one, it's the same question as before, but instead of a physical graph, it gives you the function of the graph
and the interval
use the given choices to figure out which interval gives you a negative rate of change
uhh
you can use the function itself to find the coordinates by plugging in the intervals
how could i do this
so for the first one you have -3 and 4
plug those into your equation to find their y counterparts
yesss
then find the rate of change
and figure out which interval has a negative rate of change
the first coordinate would be (-3,5), yes
you're talking about 4a?
^
for a your x-coordinates should just be the intervals
i dont understand
-3 should be the x1 coordinate and 4 should be the x2 coordinate
ohh
you have an interval for the function right? -3<t<4
yes
yes that makes sense
plug -3 into h(x) and it spits out a value, that's your y1 coordinate, and you do the same with x=4 to get your y2 coordinate
i got 5 and 54
is this how yo do it ?
@hearty arch
<@&286206848099549185> 😭
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Is the answer 3/2 or 3/root10
This is her work but if I follow it then idk where 2 came from in the bottom
I get root 10
OK, let me try.
3 squared is 9 plus 1 is ten
(x - 1)^2 + (3x + 1 - 1)^2 = x^2 - 2x + 2 + 9x^2 = 10 x^2 - 2x + 2
20 x - 2 = 0
20 x = 2
x = 1/10
(1/10 - 1)^2 + (3(1/10))^2 = 81/100 + 9/100 = 90/100 = 9/10
sqrt(9/10) = 3/sqrt(10).
So, I think you're right.
😭
So annoying this TA keeps getting stuff wrong and she’s the one grading my exams
Also one more thing I don’t remember how to solve
happened to me once, a quick email to the professor fixed everything
Plus, you can prove it's not 3/2 by using x = 0, so you get (x, 3x + 1) = (0, 1), which is 1 from (1, 1).
So, the minimum distance is less than or equal to 1.
Where do I even start here
derivative of the inverse
Idk any other way
@nova pendant Has your question been resolved?
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I have a question about this
For the 15 degree angle in the semi circle
to find the area of it
do we plugin 30 degrees into the sector formula
30/360 x pi3^2
or 15 degrees
because its an inscribed angle
@crimson sedge Has your question been resolved?
<@&286206848099549185>
You find the area with the 15° and then subtract it from the area of the big sector (the 30°)
I’m not sure about the use of the semi circle
thats not my question
i just wanted to ask if we input 30 degrees or 15 degrees into the sector formula
as it is an inscribed angle
Yeah I mentioned those two because I wasn’t sure which sector you were talking about
For the smaller one, 15
Bigger one, 30
lol still not my question
okay lemme explain
for that small 15 degree angle in the circle
since its an inscribed angle
do we say 30 degrees?
as it means the actual sector is 30 degrees of the circle?
Ahh you mean should we use the central angle or not
Uh I don’t think so (?) Every sector you solve you always take the inscribed angle
ok its fine
thanks anyways
ima head to sleep gn
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jstn please be patient because i was literally trying to help you figure it out two channels ago
have you tried starting from the right... that looks horrendous
where abouts
sin(2A) + sin(2B) maybe
should i phase shift cos into sin using pi/2
definitely not?? dont do things that you dont have to
i.e. dont introduce a pi into the mix
its worse enough
ok
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why can't P(A)+ P(B) exceed 1?'
as in independant even if it exceeds p(A*B) will won't allow to go beyond 1 as a whole
I am not so sure what if A and B both are guaranteed to happen then won't the sum be 2?
like take A to be the event of getting 1-6 on a dice roll and B be the event of getting either a head or a tail
then p(A)=1 and p(B)=1, then the sum is 2?
the probability of getting both 1-6 on a dice AND either a head or tails on a coin is still 100%
not any greater
oh wait i understand you, p(A) + p(B), not p(A and B)
@raw wren Has your question been resolved?
yep, it's just given that they are independent NOT that they're mutually exclusive
yeah sorry i was misunderstanding the question, im pretty sure p(A) + p(B) can be independant and still greater than 1
so can it be greater than one
yeah
answer is D though
yeah because you cant figure out anything just from that
so does it mean it can be greater than 1 also less than 1 is possible
but in the explaination they said it can't exceed 1
it can be less than that but can;t exeed they said
that confused me
im pretty sure it cant exceed 1 if they are mutually exclusive, but if they are independant they can be
is the explaination wrong
exactly
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Quick question: does anyone know why reversing the process of differentiation over a specific interval yields the area below the curve at that interval?
it's called the fundamental theorem of calculus
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f : R --> R is a non-constant twice differentiable function such that f(x) = f(4 - x), and f(x) = 0 has atleast two distinct repeated roots in (2, 4). What is the minimum number of roots for f''(x) = 0 in [0, 4]?
heavy machinery, this server
!show
Show your work, and if possible, explain where you are stuck.
i would if i had any
i cant seem to wrap my head around how id go about doing this
What is the minimum number of roots for f''(x) = 0 in [0, 4]?
is the question about roots of f(x) or f''(x) ?
do you recognize symmetry of f?
about x = 4?
nah

f(x) = f(4-x) implies f is symmetric about x=2
so whatever repeated roots in f(x) on (2, 4), it also has those on (0,2)
I see
which means theres a total of 4 distinct roots in (0, 4)?
or more specifically (0, 2) u (2, 4)
if they're repeated it implies the curve is tangent to the axis at that point, right?
yes
right uh so f'(x) has 4 roots as well?
you're on the right track

is it necessary for those roots to be repeated as well?
cuz if I take a function that has repeated roots and has the axis as a tangent like x^3
0 has multiplicity 3
and the derivative has multiplicity 2
if f(x) has a root repeated n times then its derivative has same root repeated n-1 times
oh is that a property?
well more of a result
interesting, which means none of the roots are repeated
i.e. the graph cuts the axis
i can see it for polynomials
i suppose it only happens for polynomials though 😅
@dire geode is the answer 3? (sorry for the ping)
its 2 i think
4 roots, none repeated, implies theres 2 minima and a maxima right?
wait a minute let me process
there are 4 DISTINCT roots yes
each with multiplicity 2
the derivative is 0 at those points since the x axis is tangent to the curve
which implies f'(x) has 4 roots?
wheres the fallacy here?
no no
the graph cuts x axis
that doesnt mean x axis is tangent to graph
if f(a) = 0 that doesnt mean f'(a) = 0
it can be both right, tangent and cutting
no
yeah but repeated roots implies tangency?
what about the tangent to y = x^3 at x = 0?
it is the x axis
tangent, and crossing
not with every graph
was riemann incorrect though
idk
or am i simply being narrowminded and viewing this whole concoction through the eyes of polynomial functions
but f''(x) = 0 implies an inflection point for f(x)
and isnt it standard nature for the tangent to cross the graph at an inflection point?
yes
when talking about "repeated roots", what other types of functions come to mind?
surely only polynomials, i cannot think of any others
yeah
so why again am I incorrect to assume that the x axis is tangent to the curve
regardless of wether or not it cuts the curve
,w plot x^2 + 2x + 1
yes my point exactly imagine 4 of those bumps
,w plot y = ((x - 1)(x - 2)(x - 3)(x - 4))^2
this sortathing
oh wait, you talking about just repeated roots?
um
i wanted to know if this was incorrect
,w plot y = d/dx(((x - 1)(x - 2)(x - 3)(x - 4))^2)
oh boy
yeah so notice how this particular one CUTS the axis at all those points?
but since we're talking about minimum...
(in my question)
ill figure something out
thank you @junior dome and @dire geode ❤️
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How do i continue?
is this supposed to be generating functions?
yes
apologies for the writing 🥲
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Please explain the red highlighted part:
what is the definition of a (cumulative) distribution function
@crimson sedge Has your question been resolved?
That I know.
I can't understand why it's 1 if x > 2pi
Explain what the definition is and then perhaps it will become clear
I think, this sums it well 😀
@crystal raptor Sorry, but I still don’t understand why it’s 1 if x > 2 * pi.
You have only shown the density P(x). you need the "cumulative distribution function"
find that in your notes/book
Thank you for this hint.
take that, @crystal raptor
I am sorry, I still don’t understand it.
I understand for continuous random variable but not for the discrete random variable.
Please help.
show the cumulative distribution function
this is a continuous random variable
you gotta point out where you don't understand the definition of distribution function
Red underlined part.
that's a specific distribution function
correct
calculate this
for three cases of x
Yes, I understood the first two cases.
I can’t understand why it’s 1 for the third case?
Did you calculate P(X <= 2pi)?
Do you know how to calculate P(X <= x) using integrals?
Okay, yes. Now it makes sense.
Thank you for being patient and explaining me this.
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is cos3AcosA the same as cos(3A+A)?
no, cos(x)cos(y) is not generally equal to cos(x+y)
I see
I'm guessing you've been studying double angle identities
and sum/difference identities?
I haven't tried this yet but that seems like the most straightforward approach, yeah
alright, btw quick question, why is cos 3A not the same with CosA
not sure what you mean by 'not the same'
maybe I should clarify, why can't I merge them onto cos4A
oh, well, basically same answer as this
cos(3A)cos(A) is not the same as cos(3A+A)
oh is it beccause if we were to assume A is a number, 3A and A are not the same number
hence we can't just put them together?
even if they were the same number, cos(A)cos(A) is not the same as cos(2A)
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no prob 👍
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can someone help me
Use linearity probably
i'm not certain you can even apply this
the expectation of a ratio isnt the ratio of expectations is it?
i cant solve it
but there is some discussion https://math.stackexchange.com/questions/2136004/expectation-of-ratio-of-sums-of-i-i-d-random-variables-whats-wrong-with-the-s
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So I’m trying to learn about sufficiency and completeness of statistics.
A statistic is just a function of my RV’s.
A sufficient statistic is one that contains enough information about the sample to create a MVUE? Or just an unbiased estimator of my parameters
I’m given both that sufficient statistic corresponds to particular parameters and also a sufficient statistic could be a vector
.coose
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Suppose $T$ and $U$ are linear transformations from $\R^n$ to $\R^n$ such that $\map T{U\vb x} = \vb x$ for all $\vb x$ in $\R^n$. Is it true that $\map U{T\vb x}= \vb x$ for all $\vb x$ in $\R^n$?
I'm trying to prove this, but I am quite lost on how to word it exactly
Can I just say something like "Let A be the standard matrix of U, then the transformation U is invertible iff A is invertible"
I already proved that earlier, so taking it as fact, if U is invertible and T is inverse, then it should be symmetric because AA^-1 = I and A^-1A = I?
Am I bullshitting this too much or
well you have to use that the matrices are square
the claim wouldn't be true otherwise
this mostly is a question of what theorems you already know
no
And like, the opposite
that it implies A^-1 A=I
well the notation is bad because we are already assuming its the inverse
Is it common to just branch out this much
Like to prove x you have to prove y and to prove y you to have to prove z
well proofs get longer
although so far you haven't really done anything except use that linear transformations and matrices are essentially the same thing
you just translated it, but all the next steps you could also write in terms of linear transformations directly
This feels like something I should know
Can't you just say like
A = B^-1
By right hand multiplication
Then like
I already found myself answering a question in 2 pages in exams. Sometimes it's the simplest way, sometimes it's the expected way or even the only way
B(B^-1) = I
you dont know that B^-1 exists
in terms of injective and surjective, you have to show that if A is surjective, then it is injective
(prove that AB=I means A is surjective)
Well
This amounts to proving that A is a n x n matrix of linearly independent columns
yeah at some point it gets natural. "oh we just have to show this and that. oh whoops that already took 2 pages"
You can build a counterexample?
do you know the big matrix invertibility theorem?
Suppose there exists a m x n matrix A such that AD = I_m, but this just implies that A is square either way
with like 10 different statements which are all equivalent to a matrix being invertible?
This feels easy to do but somehow I am always getting it wrong
Idk hmm
I mean if a is true, then A^-1 works for C, so (a) -> (j) and (k)
But we are not supposing A is invertible
Yeah sorry I will close this channel I'm just massively confused at the moment
Maybe I'll get it soon
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any idea how to simplify it?
what should I do?
I am not sure how will partial fractions work here
I have to find it's laplace inverse transform
Anyone?
don't worry about this part, Simplifying it is all what matters now
just help me factorise this fraction somehow
oh
Why didn't I try finding its roots
okay good idea
wow it works
thanks
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I have to look for asymptotes
Do periodic functions not have a non vertical asymptote?
tan(x) is periodic and has vertical asymptotes for example
I mean non vertical
Oh sorry, then the only case would be a constant function
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Hi
I have a dumb question
🙂
I want to transform the next general conic equation to the equation of a hyperbole
$x^2-y^2+6x+8=0$
Kangaroo
Kangaroo
$(x+3)^2+6x-1=0$
Kangaroo
oh
where is the y²?
$(x+3)^2-y^2-1=0$
Kangaroo
then first try it by urself dude
why you say that ? I already tried, I am stuck here
Talk me with respect, no body is asking for your help
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it's geometric series where $a = 1, r = 4$, sum is:
$$a\frac{1-r^n}{1-r}=1 \cdot \frac{1-4^n}{1-4}=\frac13 (4^n-1)$$
Modus
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I need to show that this limit exists and then find the limit
My intuition says 1 but
I gotta use concepts ive learnt in class, which include epsilon n or sandwich theorem
@unborn pike Has your question been resolved?
you can use l'hopital
write n^(1/n) = e^(ln(n^(1/n))) = e^(ln(n)/n)
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hey i need help with math
?
please can you help me with math

Nobody can help, until you ask.
look, here is the old guy
i cant do linear equations
old guy
HELP PLEASE
ask a specific question
We can't help if you don't tell us what to help with
@winged lagoon Has your question been resolved?
this was one of the help channels of all time
read all the advice people gave and open a new channel
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How do i find this
,w solve 1/2 - xe^x = 0
Wihtout calculator
learn Lambert W function
Ok
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I need help with this question. I initially god 3/5 as an answer.
I know that since they are similar triangles and that the sides correspond to one another, they would share the same triginometric values.
Answer is B though
triangle is suspicious
that diagram doesnt make sense
How so?
how can hypoteneuse not be the biggest side?
i dont even know tbh'
yeah
in a right triangle the hypotenuse is always the longest side
oh wait yeah how even am i supposed to do this question without where the angles are located?
there's a very famous theorem about right triangles
probably the most famous theorem
ok what is it?
the Pythagorean theorem, have you heard of it?
yeah so it applies here
I don’t understand how it would apply in this scenario
ah, see it works both ways
if you have a triangle that satisfies the Pyth theorem then that triangle is a right triangle
Okay
So because it’s a 3 4 5 triangle it’s a right triangle
Got it
I just don’t get how that would take us a step closer to finding the answer
well, now we know it's a right triangle
and we know which side is which
in particular we know that BC is the hypotenuse and is 5
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I need help it says find each value if g(x)=x^2-x and they give me g(5n) to plug in how do I solve
As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.
oh apologies
And your solution was wrong at that.
it wa a substitution, not a solution
I'm saying your solution, as in the answer to the question, was wrong.
x, the parameter of the equation is a number.
5n is also a number.
How would you find g(2)
Plug in 2 for all the x’s
Oh ok
So what would you do for g(5n)
No, consider this:
Rather than 2
substitute in 1+1
(5n)^2 but yes
and tell us what you get
??? How is that incorrect guys
!nosols
As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.
Can't you see what I'm doing
He got it?