#help-0
1 messages · Page 426 of 1
$\sum_{k=0}^ {k} a_k= a_0+a_1 + a_2 + a_3 + \ldots + a_k$
.doc
oh yeah, so i can treat it as a variable right? it would make sense
yes
It’s really what a variable should be
plug k, you get sum upto (k+1)
i have to go now,
Regarding your question on integral as a sum
recall, integration can be seen as sum of rectangles
this means, it can be expressed as a series
i would suggest you to look into Reimann integral for this
yes no problem thank you so much great great great help
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Say u have 2 types of criteria, getting at least 1 spade and getting at least 1 face card
the user then draws 3 cards from a standard deck of cards
if x represents the number of criteria that is succesfuly met
then how would i caclulate the probability of 0, 1, or all 2 criterions being met
@eager cedar Has your question been resolved?
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can someone walk me through this one?
does this seem right?
The approximations look good to me.
how bout the equation of the line
Looks good, but I would write y = -6x+7.
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Statistics: not sure how to do it
thanks in advance guys
is it just 0.012 or 0.164?
<@&286206848099549185> sorry guys
0.164
On what occasion would the answer be 0.012 then?
wait nvm sorry
I'm stupid
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✅
Sorry, but isn't this a one sided test? So shouldn't I divide the P-value by two?
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That is a diagram and scenario of a satellite rotates around Earth
I just assume the mass of them as m and M respectively
rotating*
the Earth*
minor mistake tbh
Looks correct
My question is, if there’s some external force imposed on the satellite and makes the velocity of it to increase
no there isn't
I haven’t finished yet
you’re using a uniform circular motion model
okay continue
Would the distance between the satellite and Earth increase or decrease
Let just assume the distance between the satellite and Earth increase or decrease as r
the tangential velocity, I’m assuming?
Yes
then the answer would be yes
increase if the tangential velocity increases, decrease if the tangential velocity decreases
How would you justify your answer
hm
$\frac{GMm}{r^2} = \frac{mv^2}{r}$
dragonbreath
you can solve for v here
which gives orbital velocity at distance r
(technically it's the required velocity for an object to stay in motion around a center body without either (a) crashing into it due to gravity or (b) shoots off into space due a too large velocity)
and that too large velocity is given by this relation
The results seems like if the satellite’s velocity increases then the r would be smaller
dragonbreath
larger v = smaller r
Sure
which is kind of awkward

That’s quite counterintuitive isn’t it
yes
Do you have any clue?
For most of ppl think the r would increase if v increased
smth seems wrong to me...
use kinematics its already a satellite...
Currently you've solved Fg = Frot to r = GM/v² and under the assumption that the gravitational force remains constant, then yes, if you want your satellite to be closer to earth
me thinks these are two different kinds of velocities
then it has to move faster
If you move the satellite further from earth then it has to move slower to maintain its orbit
I mean that is what would happen, if somethings velocity would increase it does "escape" the gravitational pull of the central body
if r is too big then it won't be dragged by its gravitational force
and the first relation won't hold
OH, that's right something does have to move faster to remain in orbit if it is closer
Sure the pull is stronger
all above calculations were done with the assumption that the gravitational force remains constant
and only r & v are allowed to change
but we're talking about an external force are we not?
Yes
suppose the rocket suddenly turns on its boosters
think about swinging a ball tied to a rope around your head
if you spin faster and faster, but keep the radius the same
the rope will snap
then if the velocity is greater than sqrt(2GM/r) it will leave the planet's orbit
so the ball has been trying to move outwards, as the spinning gets faster
that's why I thought the rocket would move out too
as it's tangential velocity increased
What if gravitational force isn’t constant? Like I impose a external force to the satellite and makes the tangential speed of it to increase, then would the r become smaller?
I'm gonna hold firm to my position and say no
r should become larger
but
I am willing to be shown wrong
afaik, the GMm/r^2 = mv^2/r assume uniform circular motion
That force must lie in the center of the earth.
but turning on the thrusters is not uniform
otherwise you lose the circular orbit
which means your relation Fg = Frot with simple circle orbit isn't valid anymore
you can either alter the force of the earth (which would be your added external force)
or determine the properties of the satellite in a different system of forces
because if you for instance had another force outside the earth
The satellite won't follow a circle orbit anymore, but instead an ellipse, or an arbitrary connection of two ellipsis or it collapses
(well it'd only collapse if we're given starting conditions instead of the assumption of a stable orbit)
My mind blown
The fact that the track might become a ellipse is totally out of my expectation
Sure, 2-body-system
Ah, I remember it
What is “Frot” by any chance? I
Frot = rotational centripetal force
which means you have a force from a single point
I see
not multiple
Note that the centrifugal force
is a, uh how do you say that in english
"apparent force"?
wrong force?
inexistent
idk
normal force?
No it doesn't exist, there is no force pushing the satellite outwards
Fictitious Force?
Yep
You only have one force, which is your centripetal force
in this case gravity
If you look at atoms instead
It'd be a different force
But it's still centripetal
meaning towards the center
and what allows the circular movement is that the body which orbits already has an initial movement
so like in a carousel, if there was no force you'd simply move towards and fly off the carousel
Not directly outward, but in the direction you were moving
I'm not on my setup otherwise I'd draw it
the carousel is the typical example to exemplify that there is no centrifugal force
in any gravitational field
@cinder sundial ok but let's briefly look at what you mentioned before, changing the force
eg let's say we increase the gravitational force of the earth by a factor of 2
so now
2 Fg = Frot
Because the centripetal force is now twice the initial gravitational force
2 GMm/r² = mv²/r
which also solves to
r = 2GM/v²
Note that we now also have the factor 2 in this relationship
which means we can scale the radius of the satellite orbit by a factor of 2 with the velocity unchanged
to be stable in this new gravitational field again
or solving for v:
v = √(2GM/r)
we'd need √2 times the initial velocity to be stable with an unchanged radius
We could also change both radius and velocity, only the equation must be satisfied @cinder sundial
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is 0^-1 illegal
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How can I get X alone ?
okay
how can i factor out x here?
ok i got x now
thank you so much
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How do i solve this question? cant find their age
5 years (hence?) , the age of jacobs .....
well first write the question as a equation
Age of jacob = x, age of son = y.
what does 5 years hence even mean?
so 5 years later x + 5 = 3(y+5)?
yeah
5 years later
oh ok
no
actually nvm its correct
do the same with the other sentence
so then 5 years before x-5=7(y-5)
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If X1, X2,..., 1991 are strictly positive numbers and x1 + x2 + .... + X 1991 = 1, show that 2(√x1(x2 + x3 + ... + X1991) + √ x2(x1+x3 + ... + x1991) + ... + √x1991 (x1 + x2 + ... + X1990)) <1991
The square roots can be simplified to sqrt(xn(1-xn)). We know that 0<xn<1.
If you could prove that sqrt(xn)-xn is always smaller than 0.5, you would have the answer.
@scarlet drum Has your question been resolved?
Right, great tip
<@&286206848099549185>
@scarlet drum
I solved it
Imma send the solution as pics
Sry some photos are flipped. And also in the beginning I simplified the expression into a sum of square roots.
What does Df mean?
The domain of the function f
Or the values of x that f can accept in R(real numbers)
You're welcome
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Greetings.
Cash prize for 1st place in URFU math Olympiad is encrypted in this equation. I need help with solving it
If you have some free time, u can try to solve it
💀
ok
well so m! will be even integer for sufficiently large m
there is also pi
n....
well
hmm
it's sus
in all seriousness though, help channel is for asking, not giving question to helpers
but.....
this looks interesting
maybe the cos is jut meant to be 1
Ok, so I need help with solving this equation
then it's 10^1 which is 10
thats the spirit
what have you tried
I've tried to Convert radical expression in the numerator
holy fuck the product
okay so
ln(e^sink) is just sink
so its sin^2(tgk) + cos^2(tgk)
that's 1
so it's just square root of 5
wait no
2^kth root of 5
5^1/2^k
5^(1/2)^k
I think it will be 1
П is multiplication, right?
yep
5^0,5 * 5^0,25 etc.
mhm
What a thing
alright so that's 1 part
now this damn limit
pi * m! / n
well
both m and n approach infinity
m! will be some large even integer
have we found n?
Aha
I feel like the limit isnt even well defined
but my honest guess is that it's pi * even integer
cosine of that would be 1
1^n is just 1
10 ^ 1 is 10
so the whole limit would be 10 i guess
Nice
Is that answer?
now this thing
not yet
We need this
Fr
so lets start with this
the antiderivative
would be
umm
y^4/4
so it would be like
something large af
(xnk)^4/2
i think
Is it going to be 0?
now this scares me
wait yes
you are right
0
y^3 is odd function
and the bounds are symmetric
the integral is zero
therefore whole the sum is zero
so this is just
integral of cosx/mn + pi^-1
indeed
cosx/mn should be quite insignficant as m approaches infinity
so we can just ignore it ig?
Idk
well if we did ignore it
which i think is right
then we would be left with integral of pi^-1
which is constant
pi^-1(n+pi) - pi^-1(n-pi)
thats
pi^-1*pi
*2
that's 2
so whole that bullshit becomes 2
10^5/2 is 50,000
thats also the amount of braincells I lost solving this
Because the prize is in rubles(((((((
ye, it is bad
yw
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If I want to approximate the value of cos(32) using differentials, the function y = cos(x) and its derivative dy = -sin(x) dx, what is the value of dx? would it be 2 if we were using cos(30)?
The problem here is degrees/radians
radians
so dx = pi/180?
if you wish to you can convert it all to radians and work with standard derivatives
2° is pi/90 radians
so dx would be pi/90
and the derivative just -sin(x)
yw
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hi
i calculated that there is a 1/6 chance amy doesnt win both games
and so 21/6
so amy loses both on 3.5 fridays
but thats wrong cause 3.5 fridays impossible
@wet minnow Has your question been resolved?
hello there @wet minnow
Since Amy win both games on 21 fridays and she only had 1/4 chance to win both games on 1 friday
the estimated number of Fridays she played is not 21
so it's not 21/6
so
so the answer isn't 3.5
Since Amy win both games on 21 fridays and she only had 1/4 chance to win both games on 1 friday
we need to find the number of Fridays with 1/4 and 21, any clue?
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Examine the discontinuity of the function given below. If the discontinuity is removable, redefine the function to make it continuous.
f(x)= 2x²-x-3/x+1
I get everything I just need clarification on the piecewise function if I did it right this time:
Here's my piecewise
f(x)={2x-3, if x≠ -1
-4, if x= -1
Feel free to correct me though
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you hvae the first part correct
but when x=-1
y should be the limit as x approaches -1 of f(x)
you might have made an arithmetic mistake
@neat dirge
Ah so -3?
not quite
Oh it's -5
yeah there you go
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How to do number 7
,rccw
,rccw
,rccw
This much
hm
Umm
nvm this is beyond me
<@&286206848099549185>
Number 7
i think if u expand 2n! and n! u get ur answer
@plain flame
$$2n! = 2n(2n-1)(2n-2)(2n-3) . . . . 3 . 2 . 1 $$
JustToPro
now if we rearrange this a bit and get all the odd values seperate (cuz we want those to stay on the numerator)
$$2n! = 2n(2n-1)(2n-2)(2n-3) . . . . 3 . 2 . 1 = [(2n-1)(2n-3) . . . . . 3 . 1][(2n)(2n-2) . . . . 4 . 2]$$
JustToPro
now we see that in the second term (the even term) its has a common factor of 2 , we can rewrite that as
$$[(2 \cdot n)(2\cdot(n-1)) . . . . 2 \cdot 2 . 2\cdot 1]$$
JustToPro
we can factor all of those 2 out , cuz 2 is multiplied constantly with all the "n" number of terms
we get $$2^n (n(n-1)(n-2) . . . . . . 3 . 2 . 1)$$ which is basically $n!$
JustToPro
so we can rewrite what u have as
Okay
$$\frac{2^n(n!)(2n-1)(2n-3) . . . 3 . 1}{n!n!} \cdot (-1)^n$$
cancel those n! and we are left with
$$\frac{2^n(2n-1)(2n-3) . . . 3 . 1}{n!}\cdot (-1)^n$$
using exponential laws / law of indices we can combine the 2 and -1
cuz they are multiplying and have the same power
I understood it very well
good
Thanks for well explained steps
np
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Wdym by putting it back in the denominator?
If I understand corrently, you need to derivate that function in dx?
What are you solving for?
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thanks fam i got it
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hi
Angles on the bottom (U, B, A, P) would be equal since its an isosceles trapezoid. So those four would be 70 degrees like angle A.
The sum of angles of quadrilaterals is 360. So 360 - 140 = 220, and the angles at the top would be equal to 110
thxx
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2nd part
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Tennis players A and B are going to play a match against each other. Determine the probability distribution for the number of sets in the match if (regardless of the outcome of previous sets) the probability that A wins a set is 0.6, when a player has won three sets.
@valid veldt Has your question been resolved?
<@&286206848099549185>
Anyone? 🥺
the left is .6 * .6 * .4 * .6
and the right one is .4 * .4 * .6 * .4
oh you meant the coefficient
@wraith stratus Yes
is a match a best out of 4?
First one to 3 i guess
so if you've played 4 sets already
and one of the players has won 3, while the other player has won 1
how can you arrange that
For me its 0.6^3 * 0.4 + 0.4^3 * 0.6 But that is wrong somehow
answer this
They snuck in 3, don't see where it's coming from.
What do you want?
ok
you've played 4 matches
player A has won 3
player B has won 1
how can you arrange the order of these wins/losses
Hmm, dont know.
Yes' that I get, so AAAB + BBBA
Uh you mean I can combinded AAAB in 3 ways and BBBA in 3 ways?
no
Oh ok
Oh I see, so thats where the multi with 3 comes from?
First one
why
Because the match is over
yes
so only AABA, ABAA, and BAAA are valid
each of those cases has probability .6^3 * .4
so it's 3 * .6^3 * .4
np
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Hello, can you help me to solve this logic exercise please?
Ex.13) Write in symbolic form, after defining a dictionary and a universal set, and analyze the validity of the following categorical reasoning, proving by rules of inference or justifying correctly:
d) All matrices having two equal rows are not invertible. Invertible matrices have nonzero determinant. The determinant of the matrix "A" is zero. Therefore, matrix "A" has two equal rows.
How can I approach it?
@upper brook Has your question been resolved?
<@&286206848099549185>
is it necessary that this reasoning is true?
no
alr because it seems like it isnt. if matrix A was invertible it would have a nonzero determinant. but maxtrix a has a determinant of 0 . Therefore it is not invertible. However, that doesnt mean that it has 2 equal rows. All matrices having 2 equal rows are not invertible isnt logically equivalent to All not invertible matrixes have 2 equal rows. Now i am not sure how this can be written down probably but thats my thinking
the problem is that we have not yet seen any matrices! the invalidity would have to be proven by logic
wdym seen any matrices?
sorry, I am using the translator, I meant that we have not yet studied matrices.
yeah i know i have no idea what the text says
i am just concluding logically that matrix A is not invertible.
@upper brook Has your question been resolved?
I did this, I don't know if it is correct
at the end I put that it is not valid
PU is universal particularization and MT modus tollens
These would be the universal set and the propositional functions
U = {x / x is a matrix}
p(x): 'x has two equal rows'.
q(x): 'x is invertible'.
r(x): 'x has a non-zero determinant'
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For #6?
ye
cuz I think there is a theorem that states like general solution is equal to basic solution + particular solution
what's rref of that matrix?
what's tthe rref of it tho
Row reduced?
I have no clue what the question is asking since there are 5 variables so why are they giving us 4 variables?
also the solutions only three variables
Oh
The last row is the solutions of the equation
For example x+y+x=4
So 4 would be the rightmost column
The first row is: a + 0b -2c -2d = 1
oh
ohhhh
usually there's a bar
ok
that makes more sense
ye c and d are free variables
and u would solve for tha
t
and then u would find the basic solutions
Ye the bar is gone
and then add teh basic solutions to the specific solutino found
and then you would get the general solution
Ok how do we know d is free
np
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I need to write sqrt(3 + sqrt(5)) as a sum of two numbers
What have you tried?
nothing tbh, no clue how to approach it
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I've been taking a couple of shots at this problem - I just don't understand why it resolves in the way that it does. I immediately think to take the limit & use L'Hopital's theorem, but that ends up looping over and over again. It's a geometric series (from what the problem is asking, I would not have immediately known that). I'm not sure where to go.
Does something like this work?
Even if so, I'm not sure how I would apply the a/(1-r) way of solving geometric series to it.
split your fraction, it's the sum of two geometric series.
Something like this, then?
which would then be something more like...
Because N is going to infinity, that (n-1) is insignifcant, right?
It's still just effectively n?
it's important for the geometric series formula, that depends on the starting value of n and the exponent.
you can use that formula on each part, since theyre both geometric
I end up getting this if I apply the a/(1-r) formula.
This is the thought process behind it - unfortunately, though, says I'm incorrect.
a should be 7/8 and 3/8
Is that because of the parenthesis?
because they're all to the power of n
you need n-1
if you just factor out the 7 you still have 8^n in the denominator
and the same with the 3
the series starts at n = 1
my bad
$\sum_{n=1}^\infty \left(\frac{7}{8}\right)^n = \frac{\frac{7}{8}}{1 - \frac{7}{8}} = \frac{\frac{7}{8}}{\frac{1}{8}} = 7$
Mercurial
same for 3
7/8 is acting both as a and r here?
How does that work? I thought that it was one or the other - if A is 7/8, then r is 1, and if R is 1, then A is 7/8.
series formula is $\sum_{n=1}^\infty a\cdot r^{n-1} = \frac{a}{1-r}$\
You have $\sum_{n=1}^\infty (\frac78)^n = \sum_{n=1}^\infty\frac78(\frac78)^{n-1}$
Zybikron
so both a and r are 7/8
I'm still not sure I understand where the 7/8 is coming from, like -
$r^n = r\cdot r^{n-1}$
Zybikron
OH
OK. To make it a geometric series, though, don't I have to get rid of that r^n immediately? I'm not starting with
I'm starting with this.
@brittle osprey Has your question been resolved?
SollyPolly
hmm i've also just looked at actual origonal question
so forget that
$\sum_{n=1}^{\infty}\left(\frac{7}{8}\right)^{n}+\sum_{n=1}^{\infty}\left(\frac{3}{8}\right)^{n}$ if you're trying to find this you can use the geometric sequence solution right off that bat
SollyPolly
$\sum_{n=1}^{\infty}\left(\frac{7}{8}\right)^{n} = \frac{\frac{7}{8}}{1-\frac{7}{8}}$
SollyPolly
no need to m-1 it
I thought geometric sequences had to start at zero.
Like - with n being anything except 1, doesn't it also stop being a geometric sequence?
It makes sense to me if in converting the starting n to zero, it becomes (7/8)^(n-1), and in doing so I get the problem I had earlier - I can't decide exactly what a vs r is. In the step of converting (7/8)n to (7/8)x(7/8)^(n-1), don't I still technically have the original function? I wouldn't have changed the starting n.
i had written this before if this helps, but i thought it was too far off from the origonal question
oh that actually works really well in terms of getting rid of that -1 that was messing with me
Just not sure how I would decide a vs r here. I doubt myteacher expects me to use the method you're laying out, the whole separation thing.
7 can't be A because of the parenthesis, right?
In the notes I was given, it was split up like this - this is probably what's -
oh yeah this is 100% what's confusing me
yeah but you see here, there is only a k in the denominator
so they have factored out the 5
and now they have a = 5 and (1/4) = r because when k = 0 this whole thing is 5. as (1/4)^0 = 1 and 5*1 = 5
I see. That makes a lot of sense. I'm not very good with exponents - my best bet for getting rid of the (n-1) (or n minus whatever else) in future problems is to split it up like you showed, right?
yes
OK, thank you. Do you mind if I take a screenshot of this conversation so I can reference it in the future?
yeah sure, its a bit of a messy convo
👍
OH-
OOOOOOOHHH
Yeah. This makes a lot more sense now.
Thanks a ton.
was the "a's the first term" comment that made it all make sense.
:D
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how do i do 15 and the last part of 18 i been stuck on it for a while
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i got 3.34 from doing
tan^-1(500-20sqrt2/20sqrt2)
got 20sqrt2 from doing 40 * sin and cos pi/4
which is sqrt2/2
like more context
this spat out 86.56
so i subracted it by 90
gave me the answer u see above which aint correct
Why is it 500- and not 500+
isnt y sin in quadrant 4
negative
southeast is quadrant 4
If it’s blowing feom@the south it’s helping
wa
THis is a draw a pretty picture kind of problem
(They were prettier before I drew 8000 of these during flight school)
You're traveling north, the wind is pushing you from behind
It's blowing from the southwest, not to
ohhh i see
The acronyms stand for head and crosswind component but it's actually a tailwind (TWC) it's just 2am and I'm sleep deprived lmao
Either way it's 500+your tailwind, and then just arctan that with your crosswind
It's a pretty soul destroying problem after doing a bunch of them you're not wrong
It does work out as 3.06 though I did check
Counter point to the entire Q though, a) my autopilot knob has increments of 1 whole degree and b) if I'm not on autopilot lord only knows I'm getting nowhere near that accuracy, so if someone told me mid flight that I was drifting by 3.064682504082 degrees I'd die of laughter; so technically you answer rounds to what would actually be flown XD
@covert dune Has your question been resolved?
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I need find whether I include the endpoints
but it seems like I am failing to simplify the expression before using a test
<@&286206848099549185>
(13/12)^n tends to infinity faster than n i believe
i haven't learned tayler yet
if (13/12)^n >= n², (13/12)^(n+1) >= 13/12 n² >= n²+2n+1 = (n+1)² for big enough n
why do both of you raise 13/12 to power of n
idk I was just reading what he was saying and avoiding taylor series just to compare an exp and a linear
if you want to check endpoints just replace directly
-1/3 - 4 is -13/4
that's why your x wasn't in the good interval so checking endpoints didn't make sense
now you can just replace x with the correct endpoints
in the og expression
I don't have paper but from head, seems like it's the harmonic serie at endpoints
so doesn't cv
wait no exponent error
(-1/3)^n/(-3)^n is 3^-n * 3^-n = 3^-2n
no prob then
another way to see it is to set y = (x-4)/3
then you're summing (-1)^n y^n/n, which converges as long as y^n/n decreases by alternating series (when y positive), if I don't make any mistake, so when -1 < y <= 1
1 < x <= 7
@gaunt elm Has your question been resolved?
where did the - sign go in your simplification, and do you just not include the n in denominator?
about the - sign, that's where the endpoint matters, it's not the same for both
for one endpoint, you get -/- = +
and for the other it alternates
but the - sign is inside of the the exponent
(-3)^n = (-1)^n * 3^n
yes
(-1/3)^n = ...
(-1)^n is alternatinc
you get (-1)^n/(-1)^n = 1 for one of the endpoints
i feel like there's something weird with your endpoints or I did something weird
yeah that one is obvious just compare to 3^-2n
its sum converges
so 3^-2n /n which is smaller
same conclusion
yes\
and the other is the same but alternating so converges too
so what is the weird part
so I did have a mistake in my other point of view earlier
let's say you take x = 7, you get the sum of (-1)^n/n
which converges
7 should be in your interval too
it says wrong so
yeah
for x = 7 it still converges
I think I = ]-1, 7] by my point above
but what in your method didn't work is an other problem, I still don't see why
(-3)^n/(-3)^(n+1) = -1/3
not -3
well it is still wrong
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✅
you should find 1 < x < 7 too tho, and 7 should be included
yes i found -1<X<7
trying endpoints now
when x = 7 it's the alternating harmonic, which converges
and when x = 1, it's the harmonic, which doesn't
wait no sign error (corrected)
oh yeah it was the sign error
I wrote -1 instead of 1
which was the beginning of all confusion
yes lol
it was the correct sign at this point in time and then I wrote something I cannot explain lmao
yeah unless you need something
I mean I don't
have a good day
but if i have it later on can i dm
ping in a help chan, I think I deac dm
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A parametric graph is given by
\begin{align*}
x &= \cos t + \frac{t}{2}, \
y &= \sin t.
\end{align*}How many times does the graph intersect itself between $x = 1$ and $x = 40$?
Dork9399
I know a few points
I know it looks like a sort of spiral graph
but I don't know how to calculate the intersections
<@&286206848099549185>
find the period of each
is calculater allowed
no
so have u learnt calculus
well cos is bound between -1 and 1
yes
and t/2 has no bounds
yes
wait
ye
what about the start
anyway erm I'm pretty sure u can tell the intersections don't occur every 2pi
yea
it's pi, but why
Here's a hint
cosx and sinx intersect at its intersection
yes
look at the function
still not getting it
ohh
is it because cos and sin intersect twice every 2pi
@plain vortex
but even then, how would I determine that the crossing happens when cosx = sinx
without desmos
@plain vortex
<@&286206848099549185>
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can someone explain how to do b. ii.
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When do we complete the square?
when you want to find the vertex of a parabola or solve for x in an equation with x^2's and x's
it's the way to combine the two when trying to rearrange equations
oh okay but how would I know to use that instead of all the other factorising methods? Infact, how would I know what to use when factorising?
@quaint sleet Has your question been resolved?
umm factoring is a huge topic but for quadratics completing the square is literally just the quadratic formula written a different way
Oh ok, could you please assist me with completing the square for 2x^2 + 7x + 3 = 0
I've looked at so many tutorials but they all do a different way and it confuses me
the main thing is that (x+c)^2=x^2+2cx+c^2, notice the 2cx
so since I like having 1x^2 in front I'd divide by 2 for x^2+7/2x+3/2=0, and now we try to complete the square on x^2+7/2x
complete the square means the x part looks like 2cx, so 7/2=2c and c=7/4, so it goes like
x^2+7/2x+3=0
(x+7/4)^2-(7/4)^2+3=0
then you'd just solve normally if that makes sense
so first step is to divide everything by the coefficient of the first number? and in this case it's 2
That doesn't seem right
Yea theres a whole variety of ways to do it
https://www.mathsisfun.com/algebra/completing-square.html
Look through this and go through your question, come back if you're stuck on something
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Honestly I think it’s just 10,10,0,0,0,0,0…
Don’t think you’re gonna get any better than that
@wintry sluice
what?
For ai
100,200,300,400 are the options 💀
Yeah so what would S be here
I mean idk maybe it’s possible to get higher
I just really don’t see how
how did you get this tho
the answer is 100
but i dont know how