#precalculus
1 messages Β· Page 6 of 1
And integration
Its easy lmao
The only thing I fear
Is trigonometry in quadrants π
Bro I remember doing that 2 yrs ago and I mugged everything up
Trigno in calculus gud tho
πΌ
Me when I see trigonometry outside the chapter trigonometry:

Me when I see trigonometry in the chapter trigonometry:

the first one was okayish, at least I didnt get completely lost
but man the b) one not able to make it work
at a) alpha=1/2 was specified so degree 30 assumption made
Tan alpha is root3/3
Means tana is 1/root3
Hmm idk why tf is quadrant shit even there
is this correct?
I told ya I don't remember shit abt quadrants anymore π
Man ig I have to revise smh
ah okay dw
Wait
Do we even need quadrants in this question?
You have tan bro
Get everything out ez
Ye
but I don't have alpha
you're supposed to be familiar with all the table values if you want to do trig, plus there's also a trig circle that features tangent and cotangent
from 0 to 90*
hΒ²=bΒ²+pΒ²
Slide me some vids smh
I forgot everything I gotta revise
AYO THIS LOOKS LIKE A WATER WHEEL'S INSIDE π
@summer ruin
Can't we just get out the values normally
Without quadrant shit?
This transparent guy comes online once then gets transparent again π
it's sqrt(3)/3 and yes
Yup 30
Degrees
Or pi/6 rads whatever ya like
@static canopy slide ans when ya done
@peak sinew i'll do c,d,e also quickly since I think I got the gist of it
oki
do u mind checking some work i did
its just an optimisation question
Oki
thank u so much
If its understandable by my side
Imagine man sending some high tech integration I'll die π
OH FUC ITS MAXIMA MINIMA
π
Wait its something else
Idk smh
Not maxima minima
its just an ordinary optimization question im pretty sure
Something they never taught me
That's y I hate education
oh lol
Why isn't everything uniform
wdym
Like I'm an indian
ah
I didn't even apply my brain smh π
@static canopy you stuck?
if sec alpha = 3 find sin(alpha) and csc(alpha)
can't figure out which degree it is
sec = 1/cos
there doesn't exist an exact representation of that angle like pi/3 or pi/6
but cos(alpha) should be 1/3
You could use a calculator to evaluate the side length ratio and the answer would be rounded
yes, but there is no table that can answer what angle produces cos(alpha) = 1/3
you have to use inverse function to represent the angle or figure out how to transform given equation to answer the questions about sine and cosecant
if sec(alpha)=3
cos(alpha) = 1/3
can sin(alpha) be found?
well otherwise this wouldn't be on a problem list
but there seems no function formula
that fits the bill to get sin
tg seems close since it includes sin/cos but I don't know tangent value
ignoring degrees, using this formula to replace cos with 1/3
sin becomes 2/3? then csc is found naturally
Pythagorean ?
@summer ruin can't he use that?
phone died, no camera on pc so I can't share answers immediately...
it's just homework of last year curriculum(which is pretty much the same this year)
@peak sinew
no combination of standard degrees sin/cos make up to a tan of 2
oh, I think I have to look towards 270degrees too
Ah yes
whats so hard then
Jesus da hell
i solved that, I'm stuck on finding sin/cos if tan=2
what
and
tan = sin/cos already
Just use Pythagorean ig
No he meant ques says tan equals 2, find sin and cos
bro just use the ratios and get the answer
tan = perpendicular/base = 2
i don't have the triangle
exactly
createeee
one ratio is enough cause sir pythagoras lived in this world
πtf
idk why you are making the simple work complex
wait lemme send you the steps
Nice
I'll follow this video: https://www.youtube.com/watch?v=IBKk7eHove8
maybe it'll clear things up
Ok ig
why perpendicular is 1 and base 2?
*2,1
and bro thats the basic definition of tangent, a trigonometric ratio π«₯
@viscid thistle
Brooo
π
I'M DYING
He did all those shit to get the value of theta
But at the end of the day man applies Pythagorean
π
Why are you crying man
Idk bro
I am an Indian too
Areee
Yaar I have bst project to do
Wed dena hai
I didn't even complete 50%
π
Bhai gajab
Yeah
You know it better
π
11th
Kyo
Oh you're my senior
Doesn't matter much lol
Koi nhi bhaiya, boards hi to hai
Are are
Nvm pcm ya pcb?
Kya lagta hai me PCB me hounga ππ
Idk man
I know some pros who have pcmb with economics
Ha bhai, I aspire to be an IITIAN

Death
That's the only word that comes to my mind
It is
Waise muze economics bohot pasand hai
Its better not to have it ngl
Aisi bat nhi muze interest ata h
Maybe
Commerce wale log shi mein legend h
*Serious Commerce Students
Yup us drawing lines for 1h in a 3h paper
π
Lemme send you one image
Please
Dekh this is one 5 mark question
Saala aadha life tables banane mai lag jaata hai
You will now say bro its just a few lines
Yeh to kuch jyada hi hai re baba
Nhi mene Statistics phadhi hai π
π
Statistics me table bana bana ke mein 10th me pagal hi ho gya tha
Abhi hamara Maths ka last chapter again Stats hone wala hai π₯²
Class 12 mai probability is there
With trigno innit ig
π
Someone said me ig
π
Probability is good ig, cause I like Permutation and Combinations
I have to check if there actually is
Aree bhai my fav class 11 chapter
Kinda Same for me
Kyonki usme koi calculations nhi π
And bas thoda bohot dimag lagana padta hai
Buai
Bhai*
Trigno hi toh change ho jaata hai 12th mai aake π
Kaise
Bhaisaab
And few quadrant shit for inverse trigno
Vo bhi I can do without quadrants for some reason π
Lol
12 mai aake I'm like wtf where did it go ποΈπποΈ
Lol
12th is easy rehh
Just be aware of fkin theory subjects
Vahi le dubta hai
if it's limitited to 180degree to 270*
-1,-1 should be used right
Thoda seh lenge π₯²
Here comes quadrants
Help him brodar
π
hello how would i solve 9^log3(15)
i cant wrap my head around this... i would be very glad if someone could help explain it to me
Very simple
Wait lemme send it to you
okay
@static canopy bro I will get to you, wait a min
Just used a log property
If you know it u know it
oh what
thank you
but
wouldnt the answer in this case be
15^2
Fk I am sorry
Yeah correct
its ok now i understand the problem
thank you a lot
Ig I should sleep now
My mind turning off
Welcome
Bro
Noe
Wait lemee see your problem again
What
Jaadoo
Where from the world sqrt(2) come from
I would agree if the answer would be sin alpha = -2/sqrt(5) and cos alpha = -1/sqrt(5)
Why did you form the triangle of -1,-1
When tan = 2 is mentioned
it's limited to the 180degree to 270* degrees
The triangle should be this
And as in 3rd quadrant sin and cos are negative
My answer is missing the negative sign
But I can't think anything other than that
the answer limits the triangle in that area
therefore: -1,-1
you made a triangle not considering the 0-360 circle
Thank god quadrants left my life
What is -1,-1 could you explain
Yes of course
x -1, y -1 represent lines perpendicular and base
I played with the magnitude
What the hell?
Bro I can't understand anything you are talking
Especially this -1,-1 stuff
I couldn't help you with this actually
Why so
Sed
Chal jaane de lemme complete the project smh
Waise apne future ka kya socha hai
Marks toh aane de pehele π
GN
g(x) = sin(2x) / cos x
gΒ΄(x) =
how do you use the uΒ΄v + uvΒ΄thing?
how do i solve this
Its a property
This video explains 'U/V Rule' of Derivative / Differentiation (Derivative of Division)
- Explained by Amit Kabra
Or just watch this better
Btw u don't even need that here
Sin2x = 2sinxcosx
You know that ryt
cancel out cosx
Now remains 2sinx
I hope ya know how to diff 2sinx
Is that the quotient rule
maybe this belongs here:
#calculus message
hello,
im working on the infinite behaviours of an inverse function
i know that the horizontal asymptote is 1. im trying to algebraically find whether y=1+ or y=1- when x tends to + and - infinity
Yeah it is
I don't think there's a directly algebraic way of finding it, but what you do is find your dominating terms on the numerator and denominator, the ones that like grow faster than the others. when you have like a poly times a poly you can judt multiply the dominating terms in each together, and every other term as you trend to infinities contributes far less than those dominating terms. in your case it comes to doing x*x on the top and bottom which simplifies to function looking like x^2 / x^2 at the infinities. cancel them out and it just looks like positive 1.
this is however times when it changes at the infinities though
I mean like
like it's not always going to be the same at both infinities
Can someone help me through the steps of prooving that d'(x)=-d(x)/x+10 when d(0)=10000?
what is d(x)?
we're missing a lot of information here. almost the entire problem, in fact. @kindred lagoon
What does the act of getting banned from this server?
Ban Theta( misspelling of TAN theta) hehehe lol
Didnβt you say almost the exact same thing 3 months ago #geometry-and-trigonometry message
β¦ at least the laugh was less exaggerated this time
@viscid thistle i agree. thanks for the help!
unsure exactly how this works butttt.. I have about two or three math problems i need help with
From sec
Get cos
Cos2x equals 2sinxcosx
So get sin from Pythagorean
Multiply and get em
Ig
Lemme try yk
Ah yes I'm right
Where does this come from?
Ok so
Let us make miu as x
Coz I don't have that symbol in my keyboard lol
So secx=-2 is given
Ryt? @hasty haven
Yeah
So what's cosx?
-1/2
Ok I get that
Then cosx=cos(2Ο/3)
X=2Ο/3
Then we know
Cos2x
Replacing x
Cos(2*2Ο/3)
And I hope ya can find the value of cos(4Ο/3)
Using the quadrant method or whichever method that has been taught to u
Is it -sqrt2/sqrt2?
Broβ¦
Cos(4Ο/3)
I got a test tomorrow
π
Alright is correct, thanks
Lol
Imagine I said this before like a dumb shit
@ivory trout
I figured it out
Ah oki
I have another question tho
The answer is 12i ryt?
Slide
Yes
Solve for k?
Lemme try
Ok lemme try while trying to make u understand
Lets simplify it first
10kΒ²=-80
Ryt?
Yes i have that
yes
2?
In the same way
This
so you would root 8
why imaginary number
Because the chapter is imaginary numbers
Lol
We are dealing with iota here remember?
yes
Yes i got that
thank you
anyone know any tips for when solving for exact values for trig identities
its the one thing i seem to struggle with
What do u mean my exactly values?
quick question but in the piecewise definition of |x| how come -x is only for x<0 and not x<=0
it doesn't matter
you can define |x| = x for x > 0 and |x| = -x for x <= 0
it's just that you don't want your function to have two definitions at one point
is there a reason for why a function shouldnt have 2 definitions at a point?
because it's not a function anymore once that happens
for one input you have two outputs
can anyone give a brief summary on absolute value functions
i understand absolute values but what about absolute value functions and equations
it's not a function though lol
it's a multi valued mapping or w/e
but definitely not a function
unless of course you say $\ln : \bC \to \mathfrak{P}(\bC)$
illuminator3 (I/you)
Let 2^x = a, 2^y = b, rewrite the system in terms of a and b
Ok so i did that.
Then i manipulated the other equation and got
2(2^x + 2^y) = 68
I subbed in a and b
and got 2(a + b) = 68
then i manipulated the first equation
and got a = 10 - b
sub it in
2(10-b) + b = 68
20 - b = 68
-b = 48
b= = -48
but i cant take a log of that :/ did i do something wrong?
your equations are wrong
its a^2 + b^2 = 68
a + b = 10
oh crap I see
yeah
8 and 2 is a solution to that btw
just by eyeballing it
there might be another too
thank you. Dang you can eyeball that, your good lol
no
i just tried 8 and 2 because they were powers of 2
and it works
ahh I see. appreciate it
np
im so dead i do not get how grpahing logs works
is it just hey first make it exponential graph that and then the log is that equation but reflected over y = x
ye
the inverse
should it be x squared here?
probably
Yep
any idea how to solve this limit
the correct answer seems to be none of the above lmao
the denominator approaches 0 so if the numerator goes to anything but 0 the limit will explode to infinity
so f(x) has to approach -4
but we don't see that in the options
Wait how do x and y cancel each other?
Radius of circle?
Then why is it just "(5/3)^2"?
Oh wait wasn't x and y = 0? Because the circle was lying on the x axis?
Yep.
Got it.
So hold up x and y are the point of intersection?
Ah sure.
rmu
Understood.
Ye I am
Lemme just
But wait there is just one coordinate.
$\sqrt{\left(\frac{5}{3} - x_1\right)^2 + \left(0 - y_1\right)^2} = \frac{5}{3}$
Wait minus not plus
V01D3D
So would this be correct?
Got it.
Wait equation for the circle? What does that exactly mean? The coordinate of the end point of radius?
Wait maybe just coordinates of the point on the circle.
With that consideration, I get it.
What happens after this though?
Wait how do I know which points can do that? do I assume a random number?
This part kinda flew over my head.
(0,0), (10/3,0), (5/3,5/3), (5/3.-(5/3)), I may have messed up I'm on choosing perpendicular points.
Wdym exactly?
All I know is that they can follow the circumference of a circle (since circle has the radius of 5/3)
FINALLY GOT IT LOL.
Brb
What problems should I work with to be comfortable?
I'll try learning them lol.
Aren't lines-parabola intersections related to quadratic equations?
Mind giving me some problems for Depressed-cubics then?
I never really solved cubics so let's try.
in my honest opinion, it's not worth learning the "general method" for solving cubics (e.g. w/ the cubic formula), but it is still useful to know how to identify rational roots of cubics, as well as to factor cubics with 1 known root.
Tan B = β where pi < B < 3pi/2 Does anyone know the solution to this problem?
the inverse function of tan for 2/3 radians is the answer for the first quadrant
since tan is first and second quadrant, you do 180-B to find both answers
to understand this, make sure you look on youtube what functions, inverse functions, and quadrants are
nick!
How do I solve for c on a double integral numerically?
I think the answer might be D. I am not sure tho.
24x^4y^5
when you look for the lcd, you want to take the highest exponents from the denominators, which is 4 and 5 and cannot exceed as it did in your choice
you can just look at the numbers and see that the lcm of 8 and 6 is 24, considering that all the answers have different coeficcients
kinda an L move on the teacher but whatever π
Aylou-210
milky
$y=atan(x-b)+c$
milky
you need some sort of initial condition
hey guys im having trouble determining the equation of a function from its graph, the form is y = ab^x
I can send a picture of the given graph
these are the two points ive used to try to solve for b
f(-1)=15
f(0)=3
what's the problem
I'm trying to determine the equation of the graph
and what is the problem you're having with it?
the problem clearly states that the function has form y=ab^x, there's no k
i solved it y = [(1/4)^(x-1)] - 1
How do you determine the inequality of a quadratic function
May you please give us an example?
expand using the formula of sin(x+y)
wavy curve method
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sorry bro, but the videos are in hindi. you should be able to understand from what is written on the board. so fat, this dude explains it the best from whoever I saw on youtube.
Sin (Ο/2 + x) = Cos x
Let x = Ο/3
Sin (90+60)= Cos (60)
Sin of 150 is 1/2, and cos of 60 is 1/2.
@dull aspen ^^^^^^
What is a real zero? Is that just another term for an x-intercept?
Thanks
$s=\frac{\sqrt{32}}{2}\sinh(2t)$
I have a book that defines a conic as the set of all points P(x,y) in a plane such that the ratio of the distance from P to a fixed point and the distance from P to a fixed line is constant. This ratio is eccentricity e. For a parabola e = 1 because it can be defined as all points equidistant between a point and a line. This makes sense, but then it goes on to define the eccentricity of a circle, ellipse, and hyperbola in terms of vertices a and b. How does this fit the definition of a conic?
it does
e = 0 circel
circle*
0 < e < 1 is ellipse
e = 1 is parabola
e > 1 is hyperbola
@viscid thistle but the definition given for an ellipse, circle, and hyperbola don't involve the distance from a point to line. It gave it in terms of distances to two points. Not a point and a line. Which is what the definition of conic mentions.
it's just some smart transformations I never thought about
but it's most likely just simple analytic geometry
heres some cool precalc notes i took #4
thank you! it all comes down to my mom who really made me lol
i kinda just use my notebook to jot down my thinking process
yeah everyone works differently
wow, nice notes!
thank you π
i love it
ty
keep it up
Dam ez stuff
idek whats going in precal rn lol
sin and cos waves are weird
but theyre pretty neat tho
Nah they g
It's just ratios
There are weirder
,w Plot[x!, {x, -5, 5}]
Bruh
lol
Can someone help me with these
you can use trig functions and that will hopefully give you an equation to solve (question 5)
@tepid yew
In number 11
Use formula of sinΒ²theta
SinΒ²x=(1-cos2x)/2
So its like (sinΒ²2x)Β²
Use formula ones then square it and use formula again if necessary
cosΒ²x=(1+cos2x)/2
In number 11 and 12, divide and multiply the eqn by 2
And use the 2 in the num, to use formula 2cosacosb and 2cosasinb respectively
I'm so envious rn that i for real wanna own that lol
haia guys
i'm doing calculus but i wanna know what if missed anything from precalc just because i'm a bit paranoid
So I thought to myself: a diagnostic might help with this issue
so bassically do you have like any pre-calc diagnostic reccomendations? (if that's alr with you guys)
uhhm sorry for the long read, thanks for ur patience
khan
a short summary of pre-req knowledge for calc is
basic algebra
functions / polynomials
exponents / logs
geo / trig
if you had a set of things with something in common, you could describe the relationship as a ratio right? like 3 out of 50 people wearing a blue shirt in a crowd and such, which is also 6% of the people. so what if you had a finite amount of relationships to an infinite amount in the set? what ratio does a number like 3 represent in comparison to all the other numbers that aren't 3 in the set of all integers for example? is 1/infinity? I don't understand
as n approaches infinity, 3/n approaches 0
(in terms of probability, if you were to pick 3 people in a group of infinitely many people, that has a 0% chance of occurring.)
fwiw probability 0 doesn't mean impossible
it means it will not happen? so yes, impossible
no
when randomly picking a number in R every number has probability 0
but they could still be picked
don't you mean the probabilities approach 0? in which that does make sense, they still can be picked but it's such a small chance
no
a more rigorous example
consider a random variable $X$ which is uniformly distributed on the interval $[0, 1]$
yes yes yes no
let $x \in [0, 1]$. if $\mathbb{P}[X = x] = \varepsilon > 0$ then because $X$ is uniformly distributed we can conclude that $[0, 1]$ contains at most $\frac{1}{\varepsilon}$ points, which is obviously false lol
what in the world is happening
yes yes yes no
so then what?
epsilon has to be 0
which is undefined
what?
1/0?
I'm in grade 11 ap stats idfk\
then don't ackhcually someone when you don't know what you're talking about
I'm just saying from my learning that when a probability of 0 is present, the event simply cannot happen
I just showed you it can
how? you showed me that the variable epsilon must be 0
we assumed that X is uniformly distributed
@cosmic girder I would like to ask you to explain like Iβm 5 haha
I believe you, Itβs just not clicking for me
so imagine you're randomly picking a ball out of an infinite container that has an endless amount of balls in it
the probability of picking a specific one is 0
but it could still happen
It's greater than 5/8
Can you define P(X=x) in a formal way...
5/sqrt 39
i mean in theory its 0+....like very small and even if u think practically its still very small....very small
the sum of the probabilities of all sample points in the sample space that are assigned the value x
no... it's 0.
ur saying 1/infinity is zero?
infinity isn't a number, you can't divide by it. but $\frac{1}{x} \to 0$ as $x \to \infty$
yes yes yes no
so this is a very dumb question but if im integrating by parts, and I asign u = x^2, what should du be? 2xdx?
yes

bruh
infinity no is numbor
0/0 is indeterminate
please do your shitposting somewhere else
Yes monsieur
This is supposing there is a minimum for P(X=x)... You're not proving anything...
are you guys familiar with this?
without specifying what r, y and x are this table is meaningless
it's circular function ...
i think he means what is o a h in this case
yes it's oppo, adja, and hypooo
Could someone help?
I'd try taking a larger picture by zooming in if at all possible
N42Β°E for 1 mile then ... N132Β°E for 1/2mile ... Can you draw it on a piece of paper?
Can u figure the coordinates after 1st mile? Then the displacement on the 1/2 mile. ?
Draw it either an app them
Sounds good
Everything is easier with pen and paper.
Show your work if you can
Can you think of a series that applies here?
I saw your finding earliert can't see it now. I've never used these notation (N42Β°E etc or 'bearing'), but in finding something that seems 10% of what I think you said you found.
Fell free to DM, but it's midnight here
X is uniformly distributed. what you're saying is nonsense
@cosmic girder ok dude you gotta chill out and try to talk to people a little nicely?...so what im saying is in our country we are taught that 1/infinity = 0.0000....1 which is a very very small number which tends to be zero but about that ball case since your thinking practically you shouldn't ignore that very small value...even if its negligible cause the chances of picking a single ball out of infinity is also very very very small... equal to negligible
Just because something has a 0% chance of happening doesnβt mean itβs impossible. @spark wind
when should i bother analysis on what a limit is
is there even a point?
not looking to become mathematician
we do actually have proof of infinite convergence, right?
"proof of infinite convergence"?
define what 0.0000...1 means
it's not even clear what you're trying to say there
infinity, convergence, proof, all these terms are only loosely related to the (definition of the) limit
π
0.00000000000000000000......1
It means there are infinite zeroes between .0 and 1
its called 0+
i mean thats what i was taught
How do?
How is it not clear
A limit in definition is essentially infinitely converging
a number just slightly greatet than 0
"infinitely converging" doesn't even make sense
infinitely isn't a term that's used relative to "convergence"
I just read that it is
A limit infinitely close to
Instead of saying I donβt make sense, correct me
a sequence a_n is said to be converging to some number A if the limit a_n as n approaches infinity is equal to A
Okay, sequences are surely a representation of, but Iβm specifically talking about calculus
calculus starts with sequences 
the definition of limits of functions is just extention of sequence definition
that would be like saying it's converging twice or 3 times or infinitely many times
Seriously? You know I meant a limit
Whereby itβs never reached but instead is infinitely closer to
itβs never reached
no that part is false
take sin(x)/x as x approaches infinity, the limit is zero, but the function also reaches the value zero infinitely many times
Iβm talking about infinitesimals
it is one
you can make that sequence arbitrarily close to zero since it's limit is zero when x -> infinity
And degrees?
?
Btw you gave an example that isnβt exactly what I was talking about
I was referring to not reaching the limit value which is the focus of my learning rn
the example I provided does reach the limit value many times, that's the whole point
But thatβs a cool fact I didnβt take into account from my statement / question
Do we have proof that something can have a limit that it reaches infinitesimally close to?
that's the definition of the limit
given any error epsilon > 0, you can choose a number N, such that for all numbers n > N the sequence a_n will be at most epsilon off from it's limit A
If we have proof for that why is there no proof for infinity?
it's not a proof, it's a definition
and similar definition can be fairly easily obtained from that one for the case when the sequence goes on to infinity
it's just needs to be negated
I know I just didnβt want to further argue seeing as how Iβve yet to read any proof for a limit and not definitions
Saying as how you answered proofs with a definition
how can there be an infinite amount of digits if it has a last digit lol?
define it rigorously
Your reasoning by contradiction was nonsense.
how so
You wrote :
let $x \in [0, 1]$. if $\mathbb{P}[X = x] = \varepsilon > 0$ then because $X$ is uniformly distributed we can conclude that $[0, 1]$ contains at most $\frac{1}{\varepsilon}$ points.
What you mean is:
Suppose P(X) has a minimum epsilon...
But you have not prove that epsilon exists.
There your reasoning by contradiction does not hold at all.
bigkafka
What you mean is: Suppose P(X) has a minimum epsilon
no, no such supposition was ever made.
they said, "Supposed P[X=x] is positive. Call this positive value epsilon."
- since the distribution is uniform, all the possibilities have the same probabilities. That's what they called epsilon. (correct me if i'm wrong)
has anyone read it?
Is there a youtube channel that explains precalc well?
Or is there a website for it?
what topic
All of precalc, I had a rough go since the start of the semester and want to get a better understanding
use khanacademy
Alright any other places?
Do you have any notes for precalc
Organic Chemistry
only God knows
does anyone know how sin and cosine actually work? why are numbers allowed to behave weirdly with them? how can f(0) be 1 for cosine?
cos90 = 0
whats the actual function/ transformation that allows these?
do degrees have special properties?
and how can you treat them like non numbers
this has to be limit related surely?
or is this only working for triangles/unit circle?
the definition of sine and cosine?
why does the cosine rule even work?
all i see is repeated formula and rules to memorise that help people work things out but never a reason why
so the trig functions were derived from triangles in circles and plotted with such knowledge, its not like you can just make a function that can do that
i first started thinking about this from this:
something which you mentioned yesterday
feels counter intuitive
theres no way sin0/0 is 1, it has to be zero
they say it is not defined unless you define it? lmao?
,, \lim_{x \to 0} \frac{\sin{x}}{x} = 1
yes yes yes no
See screenshot
so you are saying that 0.000000001 = x, you will get 0.99999999, but when you get 0 it will not work
there is still a point on the curve at x=0
or does it skip
technically writing sin(0)/0 is incorrect
it becomes undefined is there a infinitesimallly small gap between the line?
this is hard to imagine
shouldn't be too hard to imagine a single point where the function is undefined
when its infinitely small it is
i literally cannot imagine it
so a single point here you just imagine it as x=0
as a... point
thats helpful
Yeah makes things easier to think about
was it hard to imagine that 1/x is undefined for x=0?
or square root being undefined for an entire half of the real line
because a point is a point but an undefined gap being a point is weird and hard to imagine
is this relavent?
yes
having never done analysis i wouldnt understand any of this properly
maybe i shud just accept it and not try
a limit tells you what value of the function should be there depending on the surrounding points in a way
-pi/3
got a precalc exam coming up. weve just been doing trig so far. any tips on studying?
Hm.
yes they all work im not gonna list them all out
,, H_n - \ln{n} \xrightarrow[n \to \infty]{} \gamma
gamma is the euler mascheroni constant
yes yes yes no
is there a name for Hn?
nth harmonic number
$H_n = \sum_{k = 1}^n \frac{1}{k}$
yes yes yes no
Having some hard time understanding limit definitions, any suggestions to understand them better?
Whats the whole point
the point is that no matter how small (but positive) error epsilon you choose, starting from some (large, but finite) number n the error between the sequence and it's limit will be always less than the epsilon of your choice
Practice the theorems, get an understanding of how the unit circle works, make up your own problems or find problems that you can solve
love your name. i know itβs fake
thawne.
π
Yeah, it sure was. It's a bit emotional that the next season is the last one, but its time has come

