#help-27
1 messages · Page 205 of 1
we can prune a few 2T in the first two trees
HH: P1 1T P2 1H, P1 2H, P2 bluff, P1 P2 2H, P1 bluff, P2 P2 bluff, P2 P1 1H, P2 2H, P1 bluff, P2 P1 2H, P2 bluff, P1
HT: P1 1T P2 1H, P1 2H, P2 bluff, P2 P2 2T, P1 bluff, P1 P1 1H P2 2T, P1 bluff, P1 P2 bluff, P1 P1 2H, P2 bluff, P2
Sorry I'm behind, the first four tables seem right though
yeah those are right
we can probably prune more
i don't think we can actually prune anything else but also this is small enough to basically just analyse the whole game from here
P2's strategy in response to P1 playing 1T is to essentially guess what P1's coin is, and either play 1H or not
P1 is therefore given the choice of either playing 1T to let P2 guess, or guessing P2's coin
i think it's just a more complicated 50/50 though
yeah it seems like the choices don't matter again
D:
P1 1T
P2 1H, P1 2H, P2 bluff, P1
P2 2H, P1 bluff, P2
P2 bluff, P2
P1 1H, P2 2H, P1 bluff, P2
P1 2H, P2 bluff, P1
HT:
P1 1T
P2 1H, P1 2H, P2 bluff, P2
P2 2T, P1 bluff, P1
P1 1H... P1
P1 2H, P2 bluff, P2
TH:
P1 1T
P2 1H... P2
P2 2H, P1 bluff, P1
P2 bluff, P1
P1 1H, P2 2H, P1 bluff, P1
P1 2T, P2 bluff, P2
TT:
P1 1T
P2 1H... P1
P2 2T, P1 bluff, P2
P1 1H... P2
P1 2T, P2 bluff, P1```
I combined the branches that yield the same winner
oh yeah that's a good idea
that's what the ellipses represent
after 1T in HH/TH we could also combine P2's choices of 2H and bluff
since P2 knows they're equivalent
P1 1T
P2 1H, P1 2H, P2 bluff, P1
P2 2H/bluff... P2
P1 1H, P2 2H, P1 bluff, P2
P1 2H, P2 bluff, P1
HT:
P1 1T
P2 1H, P1 2H, P2 bluff, P2
P2 2T, P1 bluff, P1
P1 1H... P1
P1 2H, P2 bluff, P2
TH:
P1 1T
P2 1H... P2
P2 2H/bluff... P1
P1 1H, P2 2H, P1 bluff, P1
P1 2T, P2 bluff, P2
TT:
P1 1T
P2 1H... P1
P2 2T, P1 bluff, P2
P1 1H... P2
P1 2T, P2 bluff, P1```
so yeah it really is just, P1 either guesses P2's coin, or lets P2 guess P1's coin
yeah

Ok I'm satisfied with that answer now
thanks for your help
A bit disappointed though I was hoping we would get mixed strategies
since I think that's what we would have in the actual game with dice
i think we did get a mixed strategy, just not a very interesting one
(I guess we are technically getting mixed strategies, just not ones that matter)
yeah
it's a mixed strategy that can be played as a pure strategy
so
pure given the move history and their coin
the issue is that if they're too predictable, then P1 can play 1T (to let P2 guess the coin) only if P2 will get it wrong
but i don't know if P2 can use their own coin to work around that without needing external randomness
ok but yeah if P2 just guesses that the game is either HH or TT then i don't think there's any strategy for P1 that defeats that
yeah
after 1T
go 2T if they have T, and go 2H if they have H
and it's 50/50
well I'm content to close this now unless you have anything else you want to add
alright so basically yeah no mixed strategies lol
i'm curious now what the analysis would look like for like, a 3-sided dice
me too
at that point it would be really tedious to do by hand but we can start writing code to generate game trees
Should I open another help channel for that or?
It's a separate question technically
lel
fair enough
Ok I'll leave this open for now but I'm gonna take a break, might come back later for 3 sided dice variant
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I understand that noise canceling involves trigonometric functions, motsly sin i think? but
I cant seem to find a formula for it? I can't find any source that explains the math behind it
I know sin func is used but idk how and why
Noise canceling?
yes
As in, sound wave noises?
i think so?
Can you be more pacific?
I think it's just the same wave shifted by half a wavelength
pacific?
yeah
but like
the formulas
f(x) -> -f(x)?
idk
Basically, you have to find the function of the wave noise
yeah i understand
but generally speaking, if i were to explain this to someone I need like examples and explain why trigonmetric functions is used in noise canceling
Yeah
.
if green is noise, purple is the counter function and black is the resulting wave
see how purple changing changes black
yeah
at a = 0 it has the greatest effect
so the point of noise canceling is to detect the green wave
determine it's frequency and phase
and then create a counter sine wave that "eliminates" it
Well all sound waves can be described as a sum of sin waves
and so we take that sound wave
we split it into sin waves
we determine which of these sin waves are noise
we create counter sin waves
to eliminate them
and then we get clean sounds
that's the gist of it
oooooh
so like
sound wave itself
can be describe as a sin function
or seen as a sin function
so no formula is needed?
like this is a normal sin function formula
no, rather as a sum of sin functions
like this
here, play around with the sliders to see how they affect the resulting sound function
basically we can manipulate it
and then people figured out how to detect which sin waves make noise and which don't
so they engineer counter waves
ahhhh
okay
so is that like the only part
where it uses trigonometric function
the sound wave itself and the counter sound wave
@safe fractal
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I'm having a hard time understanding the highlighted sentence, especially "is only defined on A". May someone please help me?
basically we only allow f to give a valid output if the input is in A
so for example, if we have f(x) = x², we normally allow x to take in negative numbers as input
but we could restrict f to only positive numbers, so that only positive numbers can be taken as input for f
Okay, but what does it mean when they say 'the restriction of f to A is the same function as f, but is only defined on A'
I'm having trouble understanding 'but is only defined on A'
Is it saying that the new function has a defined subset for its original domain?
that's the same thing as saying the domain of f restricted is A, which is a subset of the domain of the original function f
So is that what it means?
@thin sequoia Has your question been resolved?
@acoustic leaf
I think i figured it out; is the article stating that such equality between the two functions given their domains only holds such that the value of the original function's argument is strictly defined as therein common values within A that it shares with the original function's domain?
<@&286206848099549185> ?
It means the domain (input set) of the restriction $f|_{a}$ is only set A which is a smaller part of the domain or input set of the original function f, which was E
Tangent
it seems like you only defined what A and E was; assuming A was a proper subset of E.
is my proposition here correct?
yep
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I try to do this,I am using cylindrical coordinates, in the question says the answer is 4/3,When I do the procedure I find that the result is pi/2
The intervals I have when I intersect the surfaces are:
0 < theta < pi
0 < r < 1
0 < y < (1-r(Cos(theta))
this is correct?
im using a transalor because my english is bad,the important part of the problem is this, it is a semi-cylinder whose equation is x^2+z=1 and a surface x+y=1,that intersects the planes y=0, z=0
<@&286206848099549185> ,I need to find the volume generated by these surfaces, but I can't get to the supposedly correct result.
@covert nexus Has your question been resolved?
@covert nexus Has your question been resolved?
the volume of a semi-circle is 0.5 (πr^2h)
Yes, but it is a problem of integrals, of an infinite semi-cylinder that intersects other surfaces of which I must find a volume
uno minuto, im translating the question
find the volume of the solid limited by the cylinder x^2 + z = 1 and by the planes x+ y =1, y = 0, and z = 0
Lo siento, no he aprendido integrales 3D pero este video me ayudará, hay subtítulos en español.
o esperar para un otra persona
thanks for the try too
de nada
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Can someone explain to me how |f(x) - L| < $\epsilon$ is true for $\epsilon > 0$
TheKingPin
for the precise definition of a limit
its nonsense
it should equal episilon
epsilon represents the distance between f(x) and L
and im looking at the triangle inequality proof for it
which is true up to the point the absolute value is added
$ - \epsilon$ < (x-c) < $\epsilon $
I can offer a counterexample to this notion
please
Consider a function that is identically equal to 1 apart from at the point x=a
at x=a, say that it's equal to 2
ekafeman
so a is 1 away from x?
ekafeman
What doesn't exist?
the function
Do you know what the graph looks like?
im not sure what im looking at
Have you tried drawing it?
again, im not sure what im looking at
What are you unsure of?
the entire piece wise function
ahhhhh ok
yea that's why we allow for an epsilon of room when it comes to the vertical line test
ya, i know for limits thats why you usually dont let x=a
nice
so back *to the OG question
on the triangle inequality stuff
which bit looks strange for you?
|f(x) - L| < $\epsilon$ is true for $\epsilon > 0$
TheKingPin
I think maybe that's not the full statement
(because it doesn't refer to what x can be)
do you have the OG passage where it comes from?
yes
Book of Proofs
precise definition of limits
let me see if i can screen shot it
i hope thats visible
do you not recommend reading this book for calculus? cause i do agree its a bit confusing
im kinda delaying reading understanding analysis by abbott
but i think its just hurting me
most books are fine and you're doing the sensible thing by asking here
ok
yes, i understand why it has to be ggreater than 0
the idea of limits is that you consider the behaviour around the point (not necessarily at the point)
ah ok
my confusion is that the right side should be = not <
cause delta is the distance between x and c
ok so for the real numbers, both are correct
the diagram does confuse things but from what i can tell c is delta away from x such that -delta < x-c < delta
wait, really?
💯
I remember there being a nice stackexchange answer I read a while back that really dug into it
I'll try link it
(I believe using strict inequalities is because there's some theory later on where you generalise from open intervals like (c, c+d) to open sets e.g. a ball of radius in R^3 around some point c and it just matches up nicer with conventions)
yea this answer
sweet
one more small question
for definition 13.2 in the book
why is f: X -> R
why is it not R to R?
probably just to demonstrate that this works for functions defined on subsets of the real line
sometimes you'll have like the positive branch of y^2 = x
gotcha, that makes sense
yea
only defined for x >= 0
just for generality's sake
you're doing great btw
good questions and understanding
don't get FOMO from not reading other books
the concepts are all the same 
thanks, im scared to take this course in the fall
but ill keep trying
this has been helpful
thank you
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Does "(...) T> (...)" mean the same thing as " '(...) -> (...)' is a tautology"?
Let T> denote tautological implication, -> be implication, and (...) just be some arbitrary formula
@crisp anchor Has your question been resolved?
I’d assume so based on the name ‘tautological implication’
It makes sense to me too
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hey guys, is there a good free website to prepare for igcse?
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i have a question about my math credits
@fallow tangle Has your question been resolved?

@fallow tangle Has your question been resolved?
ok
sorry im in class
ok so
last year in algebra 1
i was in 8th grade but i got injured and missed half the semster then got moved into normal level math raht year
but i got the credit for it
this year i failed 1 semester for geometry but passed the other semester
do i have to worry about retaking geometry as i already have the required 1 math credit for freshman year
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how would i do this question as dy/dx = ∞
you should practice A. Das books
these are basic stuff of ellipse
ok are you listening ?
im on part b
what are you on about
This is an ellipse question no?
take x^2 + 4xy as )
as 0
you will get mod of tan alpha as 1/4
huh
Ignore him 
And well, it's more that dy/dx is "dividing by zero", and sooooo...
ye i did part a, im on b
oh
sorry forgot to mention
no solutions?
how?
[hint: it's been mentioned somewhere here already]
substitute that back into the og equaion
where did you get this from?
Where are you dividing by zero, for dy/dx?
oh when x=3y
dude it's a problem from that exact book
this feels like hackin maths like it shouldnt work
what's up with bro reacting with weird emojis
Well, remember you want the gradient at the points furthest east and west to be undefined, after all, and those happen when you do something "naughty"
so y = sqrt(50/6)
atleast it's located on the directrix
+-?
Well, considering you're making mention of ellipses, when they're not explicitly taught in the course that OP is doing...
it can be solved that way
differential calculus and ellipse are not that far apart here
im not doing these questions from a book anyways, its from Additional Assessment Materials for Summer 2021
Anyways-
I am not really telling you with booked solutions
it's my general opinion but alr
anyways see ya
Seems about right 
yeah
thank you again
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Someone help PLEASE
how do i know the range on phi?
and theta too pls
Like in this they found the boundary on B to be in between 0 and pi for phi
idk why thats the case
this is spherical coordinates
that is the "default" range on theta and phi which allows it to reach all coordinates
theta should be between 0 and 2pi in order to get the "full circle" in the xy-plane, and phi should be from 0 to pi to cover the full range from +z axis to -z axis
which side is phi??
is it the one that gives the smallest value of phi?
while theta always goes counterclockwise?
phi is the angle with the z-axis
What are the spherical coordinates you are using?
i had another question
i figured it out the other one
for triple integrals
or double integrals
we are allowed to just group the integral with their corresponding variables like that and integrate them instead of doing one integral at a time?
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Yeah as long as the bounds don’t contain rho, theta or phi
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Does anyone personally know of a good SAT practice app that offers relevant SAT practice questions and/or has like a daily question to do or whatnot?
blue book
Does blue book offer daily things?
Also I don’t think it’s for mobile or at least I just haven’t found it
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i determined the interval to be 39/10 < x < 41/10 already but idk how to find the borders
if i replcae x theres still n+1/n+9 idk hwo to remove
As a sequence, what does that converge to?
The (n+1)/(n+9)?
My intuition says 1 but
I think with séries a lot of times I use intuition 💀
“Idk why it works but Ik its right”
Ah that means I have to divide (10x -40)^n as well right?
Well I thought e.g. putting in that 41/10 did that for you, no?
As long as you just put them in, you're mostly alright, anyways-
The fact you got 1 as a limit for the sequence, what does that tell you about the series?
No I meant like let’s say I divide the nominator by n
Oh wait
Nvm I can isolate (n+1)/n
And thats just 1
Division is too hard 😞
Ah, I see what you mean-
I meant, in here, divide the numerator and denominator of this expression with, in this case, n
Long story short these two are thanos snapped
Therefore whatever value x is except 4 means it diverges
Not quite-
You get convergence for everything in here, but
You wanna check if you converge when x = 39/10 and when x = 41/10
For which, when $x = \frac{41}{10}$, you're analysing the convergence of the series $\sum_{n = 1}^\infty \frac{n + 1}{n + 9}$, but you found that the $n$th term, $ \frac{n + 1}{n + 9}$, has a limit of 1 as $n\to\infty$...
@upper schooner
Oh yeah sorry I meant whatever is in ()^n that’s smaller than 1
Wait
I confused myself
These two diverge
They do indeed 
Wait no I’m right here
Rip
(unless you've changed the expression?)
Well, erm-
It doesn’t
What am I even saying
Anyway if 39/10 or 41/10
Whole thing inside = 1 or -1
Therefore diverge 😭
Yep, when you're at x = 41/10, the sequence converges to 1, when you're at x = 39/10, your sequence doesn't converge (of course, see the nth term test, to even have the possibility of convergence, you need that sequence limit to be zero and exactly zero)
WAIT NO I WAS RIGHT
I meant like
(10x-40)^n
If stuff between 39/10, 41/10 converge
And that’s between (-1)^n and (1)^n
Everything between -1 and 1 converge
When ^n
That’s what I meant
Ah, so you did change the expression 
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Hey guys this is a really hard excersise, how do I determine the convergence of this?
@main goblet Has your question been resolved?
<@&286206848099549185>
can you clarify the notation. does ln^2 n mean ln(ln(n)) or (ln(n))^2
assiming the latter i think the trick (or a trick) is to change the logarithms to base ten (wont effect the convergence as its just a constant multiple)
then turn the sum into a double sum, sum n = 0 to inf sum i = 10^n to 10^(n+1) - 1
then use some crude bounds, eventually you should be able to show that its less than some constant + sum 1/10^n n = k to inf
i believe
if you need some more guidance feel free to ping
@main goblet Has your question been resolved?
The second one
Say there is f^2(x)
Which equals (f(x))^2
yeah ok
i would try to avoid using that notation
it is more common that f^n (x) means f(f(...f(x))) but often just leads to confusion
it is only really with trig functions that it is totally accepted for e.g. sin^2(x) = [sin(x)]^2
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Hey i was wondering if i could just get a check on this? Thanks
@gray walrus Has your question been resolved?
Looks good
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Could i get a check on this
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I am kind of confused on 6a
Not sure how to go about proving this
Have you tried induction?
Induction wasn't mentioned in this book yet though, he only mentioned the rules of < with addition and multiplication
I got this point one sec
So I know that if x < y, and c > 0 then cx < cy, so in the case where x is not 0 then we can use this I think, after doing looking at google for help there was only one post about it and they mentioned using the fact that since
x < y then y-x > 0, and they used the fact y^n-x^n = (y-x)(x^(n-1) + x^(n-2)y...y^(n-2)x + y^(n-1) which was a problem a couple of questions before in the book, so I imagine he set it up for us to use this I think
but I was confused on something
because if we do y-x > 0
then multiply both sides by (x^(n-1)....)
to get y^n-x^n > 0
we would have multiplied by 0 but c has to be greater than 0
and thats where Im kind of confused
ohhhh
yeah just before this question we had a problem to show 0 <= a < b and 0 <= c < d then ac < bd
but I didn't understand that proof too well and moved on
I imagine this allows us to multiply both sides by (x^(n-1).....)?
[in particular, x is nonnegative and y is strictly positive, so this is strictly positive]
I thought it was just 0, this x^(n-1) + x^(n-2)y...y^(n-2)x + y^(n-1) is positive?
it is [strictly] positive - y^{n - 1} is strictly positive and all other terms are nonnegative
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How many numbers are in the list $-36, -29, -22, \ldots, 41, 48?$
938c2cc0dcc05f2b68c4287040cfcf71
you use the same thing
arithmetic sequence formula?
ye
40 

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given that 11x - 3 >= 8x + 10, state the least possible value of x if
a) x is an integer
b) x is a prime number
c) x is a rational number
I've managed to get that
x >= 4 1/3
How did you get this?
by solving
You mistyped
This correct
May I see your attempt?
yeah but why 5 for (a)?
好的
Integer
Since integer consists of whole numbers positive and negative
For b) its 5 also
For c its 4 1/3
A prime number is a +ve integer
So for b its also 5
And when we speak of rational numbers it can be any fraction
So the least possible value becomes 13/3
ah, I see, thanks y'all
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2log(3x+2)=log121
I have no idea where to start
what is your idea
you here?
first, theres a detail you can find helpful which is that 121 = 11^2
second, do you remember your log rules?
um I think there was like adding 10 or something but not really
thats about how logs work, not the rules of how to turn one log() into another log()
oh like how log is the opposite of exponents or no
thats still about how logs work
the log rules are how to turn something like log(mn) into a sum of logs
for now you only need the log rule that $\log(\text{this}^{\text{that}})=\text{that}\cdot\log(\text{this})$
mtt
for example, $\log(2^3)=3\log(2)$
mtt
oh i think it's too complicated
I will do it another time
thanks for help tho
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I havent even shown you how to use the rule
what makes you think its already too hard for you?
you also didnt get to ask for why the rule would make sense
i feel you
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oh well if you want you can try and teach me but just warning you i have literally 0 idea about anything in that question
so you’d have to explain it from the very beginning and I didn’t want to waste your time
???
hi
could you post the original question
2log(3x+2)=log121
Skill_Issue
alright, do you know $\log(a^b)=b\log(a)$
Skill_Issue
ya
you can use that
i learnt that at least
oah ok i will try rn
um ok wait im confuse abt the format
confused*
is the part in brackets like the base?
or is it just multiplying
This is basically the same thing as $$ (3x + 2)^2 = 121 $$
Reuben
the brackets is the log
Solving the quadratic is easy enough
normally when there is no number its $log_{10}(a)$
Skill_Issue
oh wait so it’s just 3 then
wdym
if you have $$ log x = log something $$ you can cancel the logs out
Reuben
because theyre the same base
or is it different with the log
Reuben
since both the logs are base 10
they can be cancelled
this expression is the same thing as 3x = 9
bbut how do i know if the log is base 10
ok and how do i know 3x = 9
because both the logs are of the same base
so hence I can just cancel them out
soo if the logs have the same base then does x just equal the same number like 3x3
or am i missing something
not sure what you mean, could you elaborate
$$\log(\text{something})=\log(\text{something else})$$
$$\text{something}=\text{something else}$$
Skill_Issue

umm like you said 3x=9 so how do I know that x is 3
what
3x = 9
x = 9/3
x = 3
what do you mean by cancel them out
ohhhh
my bad sorry
Not to be rude but but if youre having trouble with one step equations, perhaps dont approach logarithms yet
got it now?
yeah
omg sorry i just realised the 3x=9 thing is obvious
okay and one last question
so the equation is 2log(3x+2)=log121 but i got the answer from just the quadratic equation (idk if that’s the right name) than what is the 2 at the start of the equation for ?
its just multiplying
2 * log(3x+2)
it means $2 \cdot \log(3x+2)$
which happens to be the same thing as log(3x+2)^2
Skill_Issue
due to laws of logarithms
log((3x+2)^2) actually
ok so if there is a number multiplying the log it’s an exponent?
i have not done my khan academy lessons in a while so i forgot most of what i learnt
yea, my bad
you may wanna revise properties of logarithms
np
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i am doing some laplace exercises could someone explain me from where did that f(t) appeared ?
@glass root Has your question been resolved?
it's the right hand side of your ODE expressed using heaviside functions
okay but how did it get to f(t) = 10sin[u(t-0)-u(t-2pi)] - 0
u(t-2pi) means that u = 0 if t is less than 2pi and u = 1 if t is more than 2pi. Likewise, u(t-0) means that u = 0 if t is less than 0 and u = 1 if t is more than 0. You want to have a function that is equal to 10sint if t is [0, 2pi]. Thus you do:
10sin(t)u(t-0)-10sin(t)u(t-2pi)
If t is less than zero, both terms are 0, so the rhs is zero, good.
if t is between zero and 2pi, the left term is 10sin(t) while the right term is zero, making their difference 10sin(t).
if t is more than 2pi, both the left and right terms are 10sin(t), making their difference 0, as desired.
so for something like this i would have:
1u(t-0) - 1u(t-1)
and the whole f(t) would be f(t) = 1u(t-0) - 1u(t-1) - 0 ?
well the one above has one as well
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can this identity be proven? im having trouble tryna simplify it
What problem?
@muted goblet Has your question been resolved?
I was just trying out stuff to see if I can get the LHS as sin/cos
But I’m not sure if I’m even on the right track
Or if I messed up somewhere
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Did I use trig sub correctly here?
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hello, how can I prove this identity for all x element of R
Just input the value of sin(3x)
hmm, what does it do?
do you know of any formula for sin(3x)?
nope, not given
do you have a formula for sin(a+b) ?
I didn't ask if one was given, I asked if you knew of one
whether one had been taught to you or not
yes
yeah otherwise you prove it from this
not yet
$\sin(3x)=\sin(x+2x)=...$
kheerii
go nuts with that formula
i will try, thank u!
thank you
!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.
chill
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How many odd perfect squares are between $5$ and $211$?
938c2cc0dcc05f2b68c4287040cfcf71
there might be a rule that you have to wait until your other channel closes
but idk
all other channels are closed
yes
what does perfect square mean
and find the highest below 211
a number where its square root has no decimal point
,calc sqrt 211
The following error occured while calculating:
Error: Unexpected type of argument in function multiplyScalar (expected: number or Complex or BigNumber or Fraction or Unit or string or boolean, actual: function, index: 0)
,calc sqrt(211)
?
Result:
14.525839046334
so yeah
i have bad wifi rn its really laggy for me
also for simple calculations ,calc also saves msg space
after that how do I count them all
yep
so the odd numbers here are 5, 7, 9, 11, and 13
the even numbers when squared give even perfect squares
your answer is just the number of those odd numbers
between 5 and 169
but we need to count the numbers between 5 and 169 or 5 and 13?
5 and 13
only the odd ones
do you understand?
oh shit
its 3 and 13 in fact
do you understand this fully?
i can give a deeper explamation if you want
I didnt understand a single thing
I only know what an perfect odd number is
the rest I didnt understood
ph ok
oh ok
so here
you know what odd perfect square means
(perfect odd number is totally different btw)
right?
and that the number itself is odd
yeah
even numbers have even squares and odd numbers have odd squares
because of this
you can pretty much take the square root of the whole problem
okay
Result:
2.2360679774998
,calc sqrt(211)
Result:
14.525839046334
so how many odd numbers are between 2.23 and 14.52?
i mean that works
it's actually ceil(sqrt(5)) and floor(sqrt(14))
3, 5 ,7, 11,13
so the answer is 5!
its 6 then
also if you have another hyper elementary NT type question please paste it here to avoid clogging up the channels
?
if you have a related question just ask it here now
Result:
4.4721359549996
,calc sqrt(150)
Result:
12.247448713916
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can someone explain why tangent graphs has a period of 180 degrees even though tangent is a ratio of sin(x)/cos(x) which has a period of 360 degrees
in the fraction it can happen that either both sin and cos are positive or both are negative. but either way the fraction would have the same value as the - would cancel out
similarly one of them be negative or the other one but still same value for the fraction
The period needs to be 180 degrees as the values every 180 degrees, the values repeat
But you already know this.
Let's say a tan(x) period ends/begins every time the value is undefined.
This happens every 180 degrees.
Tan(x) is undefined when cos(x) is 90 or 270 degrees,
And there is 180 degrees inbetween those angles.
And if the period ends/begins everytime the value is undefined,
Then the time between period start (90) and period end (270) is 180 degrees.
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i feel its e but i like someone to confirm as i need the right answer, or give me a tool to check
im looking for the particular solution of this equation
might be called general solution also in english, not certain
you can try plugging them in and checking which of these work
e looks about right
try solving the homogeneous equation first
it should become more clear why
pluging them in where
im geting told its b , alright
b would be the solution to the homogeneous differential equation
one of the solutions at the very least
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hello, i got a question about this one slope intercept question
send a screenshot
,rccw
can you show the one before
oh that one
did they tell you what the x variable was for
like
does it correspond to lessons
or cost
typically x is for lessons and y is for cost for this kind of question
so cost of 4 lessons
7 lessons is 82
means you plug in 4 for x
yep
yes
1sec lemme understand
how did u get that?
like
how did u get the equation
?
which equation
.
np
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what is
the question remains: what isnt?
honestly i thik we shoudl ask ourselves why we exist
also i figured out the question LOL oops
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math is philosophy with too much logic
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This is a question thats pretty much just asking which of the systems seem like they describe this situation?
yeah, it's asking you to convert the word problem into equations
What are you leaning towards and why?
If you're just scribbling this down, this shouldn't matter too too much at first!
let's just start the problem from scratch, how about that?
suppose the multiple choice isn't given
im not totatly sure where to start
browneyes*2-6=blueeyes
I think you are at a great start tbh! The intuition to represent blue eyes as a variable is a great start
Yup! this is right!
and (i think this is the tricky part imo lol) how many people are there in total, assuming that there are only blue and brown eyed people on the train?
42?
yup! so that would be
browneyes + blueeyes = 42
i believe so!
wow thanks
can we do a few more examples
so i get the hang of this?
gst and pst are tax's btw
ok




