#help-0
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yes
do you see how we pieced it together
yes so the epsilon here is 1/n?
for epsilon = 1/n >0, ...?
ok
what we have is a sequence where the nth element is at most 1/n units away from x
as n gets very very very large
what happens to the distance
it becomes 0
it gets close to 0 yes
you should make this rigorous
so what we did is constructed a sequence
and now you need to show it converges to x like we want it to
showing this converges to x is almost the same argument as showing 1/n converges to 0
why is that?
because d(a_n,x) < 1/n
distance is monotonically decreasing to 0
i implore you to try and prove this sequence goes to x
i mean if the distance converges to 0 then it's all intuitive but if i need to get something similar to the limit definition with epsilon and stuff im stuck
ok
the epsilon definition should follow almost immediately
the distance converges to 0
more importantly, it converges to 0 monotonically
so the distance always gets smaller
ok so to show that a_n converges to x, let's take epsilon > 0, so to satisfy the definition i would need a n0: for all epsilon > 0, there exists n0 in N such that for all n>= n0, d(x, a_n) < epsilon; i already know that d(x, a_n) < 1/n for all n0, so we know that whatver N is, for all n>= n0, d(x, a_n) < 1/n0
then now i dont know, here we have 1/n0 but not epsilon,
ok so to show that a_n converges to x
you're done
oh
i read that as "now that"
let me read again
im not quite sure what you're trying to say
what we want is that
given some eps > 0
the distance is eventually less than epsilon
yes, that's where im stuck
can you construct a proof that a_n = 1/n converges to 0
lim 1/n when n approaches infinity
ok
for all eps > 0, exists n0 = ??, such that n >= n0 --> d(x - 1/n) < epsilon. I dont know what n0 could be
that's what im asking you to solve for
it is the exact same argument for the other sequence
first of all
if a_n = 1/n, and we are converging to 0
what is x
[you want that last bit to be d(x, a_n) < 1/n presumably] nvm just noticed
the kimit
ah ok 0
yeah
so now we can rewrite the final statement
d(x,1/n) < eps
as
d(0,1/n) < eps
what does d(0,1/n) simplify to
|1/n| < eps
have you heard of the archimedean principle
no
oh
but what is it
well it is pretty fundamental
maybe i dont remember
it says that for any eps > 0, there exists a natural number N such that 1/N < eps
ok
you mean in what context? you want a link with |1/n|?
i was asking for you to restate the second part of the principle
there exists a natural number N such that 1/N < eps
maybe i was unclear, but we have that now
so if we are given some arbitrary epsilon > 0
the archimedean principle tells us there is some natural number N so that 1/N < eps
now remember we defined a_n = 1/n
so a_N = 1/N, and d(0,a_N) = d(0,1/N) = 1/N < eps
yes so the limit is 0
mmmhh yes
how would we do that
we just check if the inequality still works if we take n bigger than N
yes perfect
now why does the inequality still work
if n >= N, then d(0,a_n) = 1/n < ...
if n>= N, 1/n <= 1/N < eps
flip the first inequality
but yes
perfect
and now we've shown d(0,a_n) < eps for all n >= some N
and in fact
we've shown it for arbitrary epsilon
so this indeed converges to 0
now everything we just did
translates to the other sequence
ohh ok i see
so i first i create the sequence a_n and then i show it converges to x and i just replace evrything with x and a_n
sort of yes
we created the sequence
and it satisfies d(x,a_n) < 1/n
if you apply the same arguments we just applied, you should be able to show that for any epsilon
d(x,a_n) < eps for all n >= some N
which is exactly convergence to x
ok thank you ๐ญ
Sorry for stalking, but i have been following through the progress and found this very inspiring
i remember back in my year one analysis, I failed to construct a sequence similar to this situation, and I bet I would never know what's happening if no one told me the answer
i feel you XD
I am glad to see maximo is guiding through patiently and precisely to reach the goal
that is generally the feeling i see from people doing this sort of exercise
and I'm also glad to see lilisworld. is getting closer to closer to understand it all!
until all the definitions click and become super natural, it's tough to see it all piece together
bruuhh thanks to maximo
i struggle a lot tho but thanks โค๏ธ
ok bye guys and thank you again!!!
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@surreal meadow
please dont ping specific helpers
I'm working on this and assuming that gamma has piecewise C1 boundary (which I think is necessary here) I can apply Green's theorem to equate it to
Austin
and then I'm stuck about how to go about maximizing this
bro \iint please
I didn't know that was a thing
i think there is an argument here that the center of mass should be at the origin
because otherwise you are wasting magnitude from the integral
center of mass of our region?
ok
if you take some region S centered at 0, and shift it in the x and/or y direction, then the integral gets smaller
if you rewrite this as
[3\iint_S,\dd A - 3\iint_S(x^2+y^2),\dd A = 3A(S) - 3\iint_S(x^2+y^2),\dd A]
maximo
you can see what i was saying about maximizing area while minimizing the distance from the origin
I do see what you mean by that
so if you humor this idea
humoring
and fix the area, we want a curve that minimizes perimeter for a given area
and alternatively
if you fix the perimeter, you want a curve that maximizes area
circle?
o
so we go polar on they ass
0 to 2pi, 0 to r
dr dtheta
and integrate it out
and then maximize that bih
I'm going to be upset with you if it is the unit circle
it should most definitely not be the unit circle
ok i take it back
im not that certain, but i doubt it is
ah shit
it probably is
i made a grave error
i subbed x^2 + y^2 for a fixed radius of 1
but x^2 + y^2 would just be r^2 for r from 0 to 1
it probably is 1
and after 1 it probably goes down
i give broski the proof and he gets mad that i shot down his guess
smh
broskis proof was
uhhh
it is probably a circle
just think about it bro
and if its a circle then
uhh
so I did the integral
we want to maximize
6pi(r_0)(1-(r_0)^2/3)
if r_0 > 1 this is negative
im gonna scream
if r_0 is 0 this is 0
[6\pi r_0(1-\frac{r_0^2}{3})]
is it 2r/3
no you buffoon
or
r^2)/3
ight
maximo
we good
distribute and derive and set = 0 and so on
@surreal meadow it is the unit circle
u bot
u r a bot
r_0 =1
wow ur sucha bot
fuck it we ball
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You have one length and an angle
that is enough information to find the other side
you can use soh cah toa to determine which one
you dont know soh cah toa?
ok
soh means
sin(angle)=opposite (o)/hypoteneuse (h)
cah means cos(angle)= adjacent/hypoteneuse
its a way of remembering
what sin is
toa means tan(angle)=opposite/adjacent
In the first image, there is an angle and two lengths
how are the two lengths related to the angle?
using soh cah toa
there is two
y and the number
y and 12cm
is the angle directly across from y?
ie is the the side y adjacent to the angle?
if it is adjacent, then would you use sin? (opposite/hypoteneuse)
so y is opposite of the angle then?
not adjacent?
since sin(50)=opposite/hypoteneuse
ok
can i call somone i need help badly
why do you say y is opposite
its not
yes
cos(50)=adjacent/hyp = y/12
soh cah toa
are you in radians mode
make sure youre in degree mode
ok
looks reasonable
idk
looks reasonable tho
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I need help with # 2
I've spent this whole weeking
trying to solve this
but I'm just slow
couldn't you say that angle AFG is congruent to angle GFE because of supplementary angles
oh
Yeah
aight
think of all the ways to prove a triangle congruent
you can say that GF is congruent because they share the same side
two sides equal?
AFG and GFE
3 steps?
I'm lost
last question, it might sound dumb
but
Introduce triangle congruence and at least 3 ways it can be applied in real life
is that a question they ask?
yes
like I know triangles
in real life
but how can they be applied
it doesnt make sense
It can be used for making triangular patterns
triangulation and how to find yourself on the globe as well as architecture/construction and engineering on top of that, geometry is by far the most applicable branch of mathematics
ye thats a good answer
thank you
thank you
no proble
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Hello
Write the polynomial in factored form and combine
Wdym
Could u explain a bit further thanks
You are given the roots so it can be written as (x-alpha)(x-alpha bar). You can rewrite alpha as a+bi
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How do I use implicit differentiation here to find dy/dx in terms of x and y
differentiate each side to start off
@twin lynx Has your question been resolved?
So 2(2y^3 + x^3) times dy/dx ( 2y^3 + x^3)
Which is equal to 1
Not dy/dx (2y^3+x^3)
d/dx (2y^3+x^3)
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So I've got the problem ((n+1)!+(n-1)!)/n! = 11
sorry, i hit send before finishing typing accidentally, I'll put the rest of my work in soon
I simplified it by doing ((n+1)n!+(n-1)!)/n! = 11
then n + 1 + (n-1)! = 11
then got to n + (n-1)! = 10
and from here, I'm stuck
(n-1)!/n! should be 1/n, so you should get n+1/n=10
sorry, I formatted it badly, the entire left side of the equation is divided by n!
I'm trying to figure out how to use the bot to format it better
so here is the original equation: $\frac{(n+1)!+(n-1)!}{n!} = 11$
kneeecaps
And here are my working steps so far:
$\frac{(n+1)n!+(n-1)!}{n!}=11\
n + 1 + (n-1)! = 11\
n + n)n-1)! = 10$
and now i've stuffed the bot again :/
sorry, im not good with this thing
when you divide (n-1)!/n!, you get 1/n because (n-1)!/(n*(n-1)!), the (n-1)!s cancel out
kneeecaps
oh ok, I completely forgot about that. So would I want to turn it into two fractions then to solve it properly? Like this:
$\frac{(n+1)n!}{n!} + \frac{(n-1)!}{n!} = 11$
yes
kneeecaps
ok, thank you so much, that helps a lot
so far I got
$\frac{(n+1)n!}{n!} + \frac{(n-1)!}{n!} = 11\
n + 1 + \frac{1}{n} = 11\
n + \frac{1}{n} = 10$
is that on the right track or have i messed something up?
kneeecaps
thats right
ok, give me a second to try and figure out the rest of it
@fast swift Has your question been resolved?
alright, so after too much time trying to format this so it is readable, I've got the rest of my working out:
$n + \frac{1}{n} = 10\
\frac{n^2+1}{n} = 10\
n^2 + 1 = 10n\
n^2 - 10n + 1 = 0\
\frac{-(-10)\pm \sqrt{-10^2 - 4 \cdot 1 \cdot 1}}{2 \cdot 1}\
\frac{10\pm \sqrt{100 - 4}}{2}\
\frac{10\pm \sqrt{96}}{2}\
\frac{10\pm \sqrt{16 \cdot 6}}{2}\
\frac{10\pm 4 \cdot \sqrt{6}}{2}\
5 \pm 2 \cdot \sqrt{6}$
kneeecaps
is that the same answer that you got or did i stuff something up?
yup, thats right
ok, thank you so much for your help
for sure
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Who says it is
But here it is the 2nd one
If we apply we get a different answer
Show
Why don't you use an integral calculator. ILATE is just a rule thumb. Give it a couple years and you end up forgetting it. Normally I just use experience when using integration by parts
,rotate
huh wait
@smoky condor Has your question been resolved?
No
@smoky condor Has your question been resolved?
No
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Hi, math newbie here. How can I find the (20x1) + (19x2) + (18x3) ... (1x20) ? any formula?
there is but it's more complicated than just doing it the dumb way
โข The radius of the spheres is 2
โขMaximum spheres will be placed in the primary cylinder, the number of spheres will be successively increased by one in subsequent cylinders.
โขThe weight of the spheres placed in the primary cylinder will be 1 gram, and the weights of the spheres placed in the other cylinders will be increased sequentially.
so I need the total weight of spheres
also radius of cylinder is 2
... can we see the entire problem please?
screenshot the whole thing
asking because i am kind of suspicious now
I translated to question from my book
i know it's not in english, you told me that by saying you translated it.
post it anyway.
ok so it's in turkish and i don't speak turkish
however that formula at the top is important!
and i didn't know until now that they gave it to you.
Right... my bad
โข The radius of the spheres is 2
โขMaximum spheres will be placed in the primary cylinder, the number of spheres will be successively increased by one in subsequent cylinders.
โขThe weight of the spheres placed in the primary cylinder will be 1 gram, and the weights of the spheres placed in the other cylinders will be increased sequentially.
did you mean that the number of spheres is DECREASED by 1 in subsequent cylinders?
yeah
and maybe "first" instead of primary
and weight increased
no
n*n+1/2
((n)*(n+1))/(2)
now there are too many parentheses
which is not incorrect but it is just clutter
n(n+1)/2
anyway ok
:0
so you have expressed the total mass of the spheres as 20 * 1 + 19 * 2 + 18 * 3 + ... + 1 * 20
Yes
YES
or in other words that's 21k - k^2
and you add that up for k from 1 to 20
so if you group the 21k terms together that's 21(1+2+...+20)
and if you group the squares together that's -(1^2+2^2+...+20^2), which you can calculate with that formula at the top
(20*(21)/2)x(21)?
do not use the letter x as a multiplication symbol
also a lot of those parentheses are redundant again, but yes
discord changes the font when I use 2 *
aight
so option D) is answer @vale wigeon Thanks a lot!!
I appreciate the help
as a last question do you have any advice for me? I want to study math in university
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solve what? what's going on?
what's F_n?
fibonacci number?
also what does this say?
@alpine sable Has your question been resolved?
what is the question?
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murphey
murphey
murphey
murphey
murphey
murphey
murphey
murphey
murphey
murphey
murphey
so what are you trying to do ?
finding the generating function of the fibonacci numbers ?
@alpine sable
what's your F_0 and F_1 here ? @alpine sable
if you have F_0 = 0 and F_1 = 1 there's no error there
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Pre Calc Help

Composite Function: [G(x)=x^3+2] [F(x)=3x-1] evaluate
isnt that a nice attitude to have... <@&268886789983436800>
So you need G(F(1))
?
Sorry Let me show u
F(1)= 3(1)-1
=3-1
= 2
Then...
G(F(1)) --> g(2)
g(x) = x^3 + 2
G(2) = 2^3 + 2
G(2) = 18
2^3 isnโt 16
Oh shit!!my bad small mistake messed me up
G(2) = 10
so my probem is that i need to make a composite function from this in a simplified equation
how do i do this?
So just do G(F(x))?
you can substitute x inside G(x) to F(x)
As G(F(x)) means calculating G(x) with setting value of x to F(x)
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I forgot how to do part b
doing part a)
gives you slope-intercept form
the gradient and y-intercept will be visible in that form
i got y = (12-x)/3
ohhh wait
there was a formula right
@gray isle
are you familiar with slope-intercept form?
i did it a while back
but ik
3 is the y intercept
3 isn't the y-intercept
y = (gradient)x + y intercept
right
@gray isle im confused on how i find the gradient and interceptt
then split this fraction
(12-x)/3
how
$\frac{p-q}{r} = \frac pr - \frac qr$
โฮฑฮผฮฉโฯโ ค
4 - x/3?
yes
So gradient is 4 and intercept is x/3
no
-x/3
y = (gradient)x + y intercept
note that the gradient the the amount being multiplied to x, (the coefficient of x, this should not contain x)
and the y-intercept is the constant being added
the gradient will be the coefficient of x in
-x/3
yes
@gray isle
hey
why is my graph
different
its not -x/3
Thatโs -2/3
Wait no
It 4/12
So 1/3
But why does it look like a -2/3 on the graph
also
should i write it as -x/3
or -1/3
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`
@coarse vale Has your question been resolved?
@coarse vale Has your question been resolved?
<@&286206848099549185>
๐จ what da hel
help..?
i cannot help you bro๐ฏ 
This is the given solution btw (still can't understand)
๐จ
With smol writing mistake sry
that looks more like computer code than math at this point
but can you help me
dont worry
u just need a warmup question
the square in between the square
is -2/3
i found the slope which was 4/12 = -1/3x
but in the graph
it doesnt look like a -1/3x
but more like a -2/3x
Have u learned differentiation?
no
i dont know nothin
im in 9th grade
Just show me the questionโ
i did the question bru
im asking
why it looks like -2/3
How will I knowโ
Look bro. I'm not google lense.
I can't just tell if a function is of what slope just by looking at itโ
I need to equation u trying to plot
i finished the thing man
its a visual question
rise/run
=
4/12
=1/3
so why it loookin like 2/3
like... sir, I haven't used that formula in my entire life.
I just
different
the equation
And that gives the slope to me.
No one rises no one runs.
sir... This is my channel rn.
And I was asking a question.
But u now intrude and demand an answer...
Without the dang question...
ok wait
i will get the question
I'm not sum dang robot that looks at a graph and goes "hm-m, that sure is tan inverse of 2/3 right there"
bruh
cmon
u shud know
Bruh... I've by hearted angles 15,75,18,72,36,54,53,37.
And none of em has 2 and 3 as non hypotenuse sides.
why
Cause no one wants those. They useless.
so
did you get the 2/3
or the 1/3
I don't get nothing.
Show me ๐ฟ
<@&286206848099549185>
1
Now be on ur way kid
dont u need help
And u not being any help.
<@&286206848099549185>
Hello ` ! Is your function
f(x)=(-cยฒ+(b-1)c-2)x + int_0^x sinยฒt+cosโดt dt ?
This is the function, yes.
since it's a decreasing function for all x in R and c in R, we will have
f'(x)<0 for all x in R and x in R
okey
looks like your solution the first 2 lines, f(x) should be f'(x) instead
and this should be non-increasing function instead of decreasing function
anyways
d(f(x))/dx
= d((-cยฒ+(b-1)c-2)x + int_0^x sinยฒt+cosโดt dt)/dx
=(-cยฒ+(b-1)c-2) + sinยฒx+cosโดx
all good till here?
Yes
now,
f'(x)โค0
we have
(-cยฒ+(b-1)c-2) + sinยฒx+cosโดx โค 0
Wait... The limit on the integration can just vanish?
Do you know the fundamental Theorem of Calculus?
I don't remember it by the name I'm afraid.
wbt "a"
no... where'd f(a) part go in 2nd equation
oh..
Okey. Pls continue with the question explanation.
d(constant)/dx = 0
ok
(-cยฒ+(b-1)c-2) + sinยฒx+cosโดx โค 0
-cยฒ+(b-1)c-2 + sinยฒx+(1-sinยฒx)ยฒ โค 0
-cยฒ+(b-1)c-2+sinยฒx+1-2sinยฒx+sinโดx โค 0
okey
sinโดx-sinยฒx-cยฒ+(b-1)c-1โค0
by completing square, we have
(sinยฒx-1/2)ยฒ-1/4-cยฒ+(b-1)c-1โค0
which arrived
(sinยฒx-1/2)ยฒ-cยฒ+(b-1)c-5/4โค0
now that's where i start to be puzzled, why would your teacher/prof choose the max value of (sinยฒx-1/2)ยฒ
which is 1/4
It's actually a question from a mock tests and the app didn't alow screen shots.
So I just jot it all down.
note that:
(sinยฒx-1/2)ยฒ
= ((2sinยฒx-1)/2)ยฒ
= (-cos(2x)/2)ยฒ
which is within [0, 1/4]
if i were to do this question, i would have different solution starting from here
Kool. Proceed.
I've kept a page empty after that solution for better explanation to myself.
so, we have
cยฒ-(b-1)c+5/4-(sinยฒx-1/2)ยฒโฅ0
sorry, typo
since this quadratic of c is always โฅ0, we have the discriminant โค 0
How?
is this ok?
Still don't get how.
What if b>4 and c<4 while a=1?
then there will be 2 distinct root
If D<0, doesn't that mean complex root?
for axยฒ+bx+cโฅ0 for a>0
it will either just touch the 0 line or not touch at all, therefore it's a repeated root or no real root
therefore the discriminant โค 0
though we are not concerned about the roots of this cยฒ-(b-1)c+5/4-(sinยฒx-1/2)ยฒ in this question
see if you understand this first
okey, so... f(x)โฅ0 means yโฅ0, thus the graph
Now I got the answer...
Thank you for the help.

U can, if u want to.
(b-1)ยฒ-4(5/4)(sinยฒx-1/2)ยฒโค0
so we have
(b-1)ยฒโค5(sinยฒx-1/2)ยฒ
oh wait
sorry
How this happenedโ
my bad
lemme do it again
(b-1)ยฒ-4((5/4)-(sinยฒx-1/2)ยฒ)โค0
there we go
bยฒ-2b+1-5+4(sinยฒx-1/2)ยฒโค0
Wait, still confused on how ths happenedโ
discriminant โค0
c is from the quadratic expression cยฒ-(b-1)c+5/4-(sinยฒx-1/2)ยฒ
yes
that's the main point
which i think it's the hardest part of the question
since we have this
let's fix 2 cases for the
bยฒ-2b+1-5+4(sinยฒx-1/2)ยฒ
it is when (sinยฒx-1/2)ยฒ is max or min
when it's max,
the quadratic of b becomes
bยฒ-2b-3โค0
when it's min,
we have
bยฒ-2b-4โค0
lemme check things a bit
sorry for taking your time
No worries.
so for both situations, we have
bยฒ-2b+1โค4
or
bยฒ-2b+1โค5
since it's an 'or' relationship, we have to choose the largest suitable range for both situations
which is b in [-1,3]U[1-โ5,1+โ5]
which finally we have
b in [1-โ5,1+โ5]
which is slightly larger than the range in the final answer of the marking scheme
that's all i think
It's given in the options, but the [-1, 3] is marked as correctโ
interesting
anyways thanks for your time, I've had a great time doing this question!
I'll jot down all this question and ask my teacher tomorrow.
Thanks to u too for helping with this.
Cheers
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I have asked this question before, but maybe someone has a shorter and less complex way to solve this?
try writing $T_r=\frac1{4(r+3)\cdot 4(r+4) \cdot 4(r+5)}=\frac1{64(r+3)(r+4)(r+5)}$
ah..
kheerii
$4^3$
Why am. I here
why is that
nah, where did that 4^3 come from

No I know how that works
lemme word the question better
at what point did we come to the conclusion that we should write 64 there

did you understand how the general term was obtained?
thats what im asking
yep
16=4(1+3), 20=4(1+4), 24=4(1+5)
oh I see and if we put 1 instead of r we get 16 20 and 24
and 4 is common so we take it out
yep
so its a sequence
correct
so I could calculate the sum
so we have defined the series
S_n = n/2 * (a1 + an)
now we need a way to add it up
no, that only applies for arithmetic series
which this is not.
its geometric then
why?
there exist many sequences which are not arithmetic or geometric
infinitely many, in fact.
an Arithmetic sequence is one in which the difference of two consecutive terms is constant
a Geometric sequenec is one in which the ratio of two consecutive terms is constant
none of those two conditions work here
yeah ur right
okay my bad its neither of those
yep
adding these terms up will be hard without some sort of cancellation
we need to find some way to cancel these terms
every neighbor fractions share two common numbers
yeah
yes, that is a key observation here
basically whenever you have a term like 1/r(r+1)(r+2)(r+3).... something like this
it can turn into a telescoping series
meaning you can manipulate that term in such a way that the intermediate terms all cancel out and you only have to calculate something at the ends of the summation
oh dang I remember using this for a less complex problem
I represented 1/(4*5) as a subtraction of two fractions or something and then cancelled common fractions
yes, you need to use a similar concept here
let me try it on my own first. Thanks
So I tried rewriting the first fraction as a subtraction of fraction
and did the same for the second one
so I get 6 smaller fractions like 1/4, 1/5, 1/6 and some of them would cancel each other but they are multiplied by some random stuff
like -14, -23 and so on which prevents the cancellation
Try writing $T_r=\frac1{64(r+3)(r+4)(r+5)} = \frac{(r+5)-(r+3)}{2\cdot 64(r+3)(r+4)(r+5)}$
kheerii
@fair vigil Has your question been resolved?
and then?
I am not sure I see what to do next
we can say $T_r = \frac1{128} [\frac1{(r+3)(r+4)}-\frac1{(r+4)(r+5)}]$
kheerii
you see how?
yeah I get this
and then should I divide these smaller fractions into even smaller ones?
or nah nvm we should be fine
then we can define $v_r = \frac1{(r+3)(r+4)}$, which gives us $T_r=\frac1{128}(v_r-v_{r+1})$
kheerii
so the next fraction will be 1/128(v_(r+1) - v_(r+2))
and that v_(r+1) will get cancelled
yep
okay lemme calculate the rest, brb
@quasi vector I got the answer. Thanks a lot!
.close
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still don't get it. What happens there?
i think those mean "using double angle formula"
sin(2x)=2sin(x)cos(x)
@cold mist Has your question been resolved?
What's stopping you from using double angle formula?
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after a reduction by p% the wardrobe costs s zlotys, a)what will be the price of this wardrobe after the increase of p%? b)Determine the price of the wardrobe before the reduction
zlotys is like dollars you know guys. I need help with it, im not sure my equation is correct.
Can you show what you tried?
It's a common misconception that raising the price of something 10% (for example) and then lowering the price by 10% will get you back to the original price, but it won't. Is that the source of your confusion?
@frigid mirage we can't help you if you don't answer...
don't worry
not really
let me edit the photo a little bit for u cuz my datas are in Polsih
Polish
ugh wait ill just write the translation write its too annyoing
- wardrobe cost
- wardrope cost after a raise
- wardrope cost before the reduction
@loud warren
,rotate
Does that say s+2p%?
OK, how did you get that?
Well, i was thinking like that: if the wardrobe's cost is now s zlotys (like dollars) . so i multiplied s * p% (To get it to the original price). so now if it has raised by another p% i did that.
im very sorry English is not my native
Let me re-read the original problem
ok ๐ญ
OK. So, if something starts at 150 and you reduce it by 20% how would you compute that?
150 * 0,80, yes?
Exactly. OK, let's say the original price was x. If you start at price x and reduce by p% what do you get?
i don't know.. i can't think rn
That will make it difficult. Do you want to continue or come back when you're ready?
OK, let's say the original price was x and you reduced it 20%. What would the new price be?
0,80x
Right! What if that was 30%?
0,70x
Now, can you do it in general for p% ?
100% = 1 (maybe this helps you)
Very close. However, if you have a 20% reduction, do you multiply by 20/100?
no, i multiply it by 0,80, yes?
Correct. So, can you change your formula to show thaT?
this forumla, eh?
Yes
x * 100/100? can we count p as 100?
Well, x*100/100 is just the same thing as x
OK, when I said 20% reduction, you said multiply by 0.8. How did you get from the 20% to the 0.8?
1 - 0,2 is 0,8
Right! So, if it's p%, what do you multiply by?
Well, right, but what do you multiply x by? When it's 20% you multiply by 0.8. When it's 30% you multiply by 0.7. When it's p % (any number for p), you multiply by what?
so if x is ex. 1 and lets say p is equal to 0,50 then:
1x * 0,50p, right? sorry if ur losing patience for me. i am in 7th grade.. and my brain does not process it so fast..
No worries ๐ Let me think if I can explain it another way
aight
So, when I give you 30% off, you divide it by 100 and subtract it from 1 to get 1-30/100 = 0.7 right?
yeah
So, if you had p in place of 30, you'd get 1-p/100. Do you see how we got that?
yea i can see that
OK, so if the price of something starts at x and we reduce it by p%, what's the reduced price?
wouldn't it be just x - p% since we don't know what p is equal to?
Well, when it's 30% off, you divide by 100, subtract from 1 and then do what to get the new price? What do you do with the 0.7 you get?
what do u mean what do i do with 0.7? its the equation to the formula.
Right, but you multiply it with the original price, right?
u mean 0,1p% by that? ๐ญ
yeah
So, the new price after p% reduction would be (100-p)/100 * x. Do you see how we got that?
okay...
So, do you see how to proceed from there?
sorry I don't... and after all the explanations u gave me i feel embarassed. don't take me as a bad student please i just don't understand it.
No, that's OK. You're not a bad student, but I'm not sure I can explain any better, so feel free to call in other helpers
ok.. but 100-p is x yes? cause we dont know what the equation is
x is the original price
alright ty.. ill try to do my best but wait can you please check if chatgpt is doing the equation good? maybe it will explain it somewhat better?
I'll wait, but ChatGPT isn't always good at math
(reading)
The text after (a) is correct, but the calculation is not. That's now how you increase something by p%
oh okay..
alright well. I guess ill leave it now. But just in case can u give the equation to this? maybe i will understand it better or at school with friends.
I'll let you work it out for yourself, sorry
alright, ty for all these explanations. have a fantastic day!



