#precalculus
1 messages Ā· Page 96 of 1
honestly doing this rigorously would be hell I can only suggest using obvious quadratic equations that follow a and b since a would essentially always be true(in this case) and u have to find a function such that b is true
that one is made by me btw
make the y positive
whatever is the direction of the x(+ or -) indicates if it goes upwards or downwards
perchance is it 2
Correct
š
A can't be true because if c is always real, it is already proven false by b
since either f(x) or g(x) would have non-real roots which means f(c) can have c as non-real
I have no idea what a leading term is
I actually made that in Korean first
And asked Gemini to translate
sooo
shhh it's a common math term I'm just trying to ragebait people
š¤
In a rough sense, normals and tangents describe how a curve interacts with a line at a point. When a light beam strikes a conic (parabola/ellipse/hyperbola), the beam reflects according to the law of reflection (which is measured with respect to the normal). For instance, a parabolic mirror can send incoming parallel light beams to a single focus. An elliptical mirror can reflect light from one focus to the other. So tangents help describe the local direction of the curve whereas normals give the direction used to predict how light beams bounce.
What about orthogonal trajectories in differential equations?
Orthogonal trajectories are just finding where the tangent of the first curve acts as the normal to the second curve (and vice versa) where the curves cross
ex. if you have curves representing lines of constant temperature in a room, then heat always flows along the orthogonal trajectories (hot to cold)
Doubt chat:
We know that e is a constant. So e raised to any power, say, x, will also be a constant. If I am correct, then why is the derivative of e^x with respect to x is e^x again? Shouldnāt it be 0, given the derivative of a constant is always 0? If there is, please show me the wrong in my thinking. Thanks š
x is a variable
the value of e^x depends on the value of x
taking the derivative of e^x wrt x,
you're considering how e^x changes as x changes
that won't be 0
d/dx e^x = e^x
is one of the definitions of e
,w graph e^x
,w graph e
So like, yeah, you're conflating two ideas. If you had e^c, d/dx(e^c) = 0
(assuming c is not a function of x)
The same reasoning would lead to the derivative of 2x being 0, since "2 is a constant, so 2 multiplied by any factor, say x, will also be a constant" .
(On the other hand, since this is #precalculus, derivatives don't exist yet at all).
Thx
Sorryā¦Iāll post such questions next timeā¦Thanks. Again.
The appropriate channel would be #calculus.
Thanks a lot
In angles of depre. and elevation, why is it (sqrt(6)-sqrt(2))
That isnāt English! I was really confused for a second!
Thatās Portuguese
Use desmos š
ull get circle equation just substitute x values and get y
Is that a min or max word problem
sub 3 and 4 into the equation, get (3,4) and (4,3)
3x+4y=25, 4x+3y=25. x-y=0, x=y. 3x+4x=25, 7x=25, x=25/7
then calculate the mutual inclination using the slopes
to get... arctan(7/24). i think
What are some exponents rules that is outside of this
If x > 0
Yeah but I feel like that doesn't need to be said
But is shouldā¦. lol
Alr.
Well then, input of log in all these should never be 0 or -ve
And I think that's all there is to log
LMAO
I wouldn't be alble to ,probably .
How about log_a b^c^d u multiply I think
multiply what
Like a to c
Like this
is this an equation you're trying to solve or something else
Thatās the only one I remember with the law of exponents
This is the law of exponents (with logs): $\log_a b^c = c \log_a b$
Alberto Z.
If you want to apply it here you will have: $$\log_a{(b^{c^d})} = {c^d}\log_a b$$
Alberto Z.
I found a good one
If you draw a picture it might give you some ideas.
no i tried ts shit 10 million times confused asf
And?
Guys
looks like pythagorean to me
Find x
Ok, and what's the issue you're facing in solving it?
does anyone know how to find range and domain??? i've been struggling on it recently and i want to know how since i believe it's fairly simple
You should try lectures in of professor leonard on YouTube, he got a playlist of precalculus.
okay, thanks!
Does anyone know any good videos or websites that can teach inverse trig functions?
š Notes on TG:- https://t.me/jeeenglishbyunacademy
ā”ļø Problem Practice sheet for ITF:- https://drive.google.com/file/d/1_Mcq86bUENMCBjBG6xgLVRy2oIk3OLKO/view?usp=sharing
Unlock the complexities of "Inverse Trigonometric Functions" with our detailed Class 12 session, perfect for JEE Main & Advanced preparation. Master key con...
<@&268886789983436800> mrbeast
Thanks
There's a persistent group of scammers who use subverted Discord accounts to post false claims that the youtuber (I think?) MrBeast has opened an online casino and is giving away large amounts of money as sign-up bonuses. All lies, of course, just the bait for an advance-fee scam.
Ohhhh I remember that
Post screenshots of his Twitter or something?
Iām never sure if itās a bunch of scammers or a virus that infects accounts
Well, screenshots that purport to be that.
Right right right
Definitely scammers. Most likely they buy the subverted accounts from someone else who farms them with cruder bait (in the vein of steam giveaways etc) -- at least one should hope there's less than one person falling for the casino scam each time they post it, so they'll need an additional source. But this is not really known.
Cruder bait lmao
Man I hope I donāt fall for stuff like that when Iām geriatric
Iām struggling how to find other 8 roots
me when roots of unity again 
just learn how to do polar
its a lot easier like that
you would get $\left(\frac{x}{x - 1}\right)^{10} = 1$
Ye
there are 10 roots by ftoa
so you made a mistake
i am still quite confident you solved it wrong
$$\frac{x}{x - 1} = {\exp(i 2\pi k / 10)}_{k = 0}^{9}$$
this should yield 1 real and 9 imaginary
wait
i see my bad
because exp(0) = 1 but x/(1-1) isnt defined
sorry š
Okay
tryhard
$ln (y)$ just means what power of e equals y?
Ujjawal Gupta
Like $e^{?} = y$
Ujjawal Gupta
?
yes
yo whats the chain rule?
its how you differentiate functions with inside functions eg e^x^2 = f(g(x)) where g(x)=x^2 and f = e^x. It belongs in #calculus
ohh right wrong channel mb
what??
wym by that
Whatās confusing
how is it painful its super easy no?
If Iām js casually differentiating my ass ALWAYS forgets chain rule
It is super easy
I js forget it
so if u say cos(2x) youd get -sin(2x)
but if u forgot
But normally like a 25/75 wrong/right
im very curious
Yes bro
hmm
thats good
what if u just always apply chain rule on anything
because it does work on everything
ln(x) using chain is still 1/x
Too much thinky thinky
or sin(x) is still cos(x)
itd get automatic no?
At some point
Hey, I heard there is a inverse pythagorean theorem
Which is 1/a^2 + 1/b^2 = 1/c^2
Does that work
would u do it tho?
for the sake of it being automatic?
fair enough
Never heard of it
But Ik or everyone knows
also yes because a^2 + b^2 = c^2 is the pythag theorem and if you raise everything to the power of -1 then you get the equation you have there,
its just the reciprocal
Okay is that useful
But
345
And where would u use it
although, a b and c cannot be zero
cuz division by zero is a no no
What abt a 345 triangle
Ik there is sin^-1, cos^-1, and tan^-1
Itās not a triangle atp š
But wait wait
For a triangle with legs of 3 and 4, hypotenuse has to be 5
Ohhh
keep in mind when you apply the power of -1 you may get a contradiction if you have 1/9 + 1/16 = 1/25, but if you have 1/9 + 1/16 = 1/c then thats okay
for normal numbers its fine tho
Itās not this itās
1/a^2 + 1/b^2 = 1/h^2
actually wait i lied
trhat was a bad example
a and b are legs and h is the altitude
yes because 1/h^2 = 1/a^2 + 1/b^2, youd just find a common denominator for 1/9 and 1/16 which is 144 and get 25/144, and then use comparison.
3-4-5 triangle and want to find the height
Oh I see now
Would it be 144/25
h^2=144/25
It would be the least distance between the right angle and the hypotenuse
h=12/5
I was misreading that
its not for c^2 its for h^2 which is the altitude
This feels like the wrong channel for ts tho
Okay
the picture explains it
3 * 4 = 5h -> 12 = 5h -> h = 2.4
You can do that?
its from the area = 1/2 base times height, and you know for specifically a 3-4-5 triangle that 1/2 * a * b = 1/2 * c * h, giving a * b = c * h
no its a bit more complicated than that
if the two legs a and b are already perpendicular to each other then you can treat leg b as the base and leg a as the height, which gives 1/2 * a * b. then now imagine rotating the triangle so it sits on its longest side, the hyp c, in this orientation the altitude h is the height giving 1/2 * c * h, and then you set them equal which implies a * b = c * h or h = (a * b)/c
Okay
Since Iām doing bearing type 2
The direction is now N/S (degrees) E/W
i would search up a visual proof
Since Iām a visual learner Iāll do yhay
That
chat idk how to do law of sines- ambiguous cases can someone help
like how do i find how many solutions from just B=36degrees, a=5, b=8 š
Thatās what Iām doing
like solve for the first angle using law of sines regularly
then do 180 - first possible angle
and if that plus the other possible angle is less than 180 2 solutions
i think its kinda been a while since i did it
From that you can find the angle of A, then itās 180-A-B=C.
Then you can use angle C to find side C
Hello I'm new here.
I think I chose wrong subject, I'm gonna change it.
Ok bye!
Hi new
What's precalculus
Stuff before calculus
(I haven't studied in the US so this might not be 100% accurate)
Calculus is a very big subject that use alot of concept that you didnt even heard about before
And pre-calculus will prepare you for that
You will see alot of new mathematic objects such as log, limits, trigonometry identities
You will also go over alot of new functions (trigonometry functions, log, expo, rational)
You should also see vectors (which are very useful in physics by the way)
I've heard that you also see matrix but I'm not sure
And more things about trigonometry because it's so useful
(Sorry for the big message)
How about 180-(A+B)=C
Same thing
Thatās what I did
Somebody give me I question, I wanna solve one real bad
Sure prove that for all $n > 2$ and positive integer $a,b,c,n$ ; there exist no $a,b,c,n$ that satisfy the equation $a^n+b^n=c^n$
multiplexer

Interesting
Yup completely lost...
Congrats
How are you supposed to solve that?
What the... You really gave me a question that took 7 years to prove xd
And that is with a PhD
I got no PhD
And works from multiple other mathematicians
Ofc i was joking
(Bullying pre-unis)
What
more like 350 years 
helloo?
hello
hi i dont really have a math problem but id like to ask for some advice regarding math.. lol is that ok?
sure
kk
i have a question what are the best AP's to take that would like significantly boost my gpa
ooh
for example: i have 2 AP classes, 2 honors, 2 regular
mmm
so 5+5+4+4+4+4=10+16=26. 26/6=4.3... ish
ooh thats thats good
ooh
(So I have like a 4.6... ish >.< still not val cus of PE and Chinese, which do not count as honors)
can someone help me with this
can i dm you if thats fine lol?
sure
What
Chat you aināt seen nothing until you take AP macro/microeconomics with a teacher that knows less than you do
fahh
sounds um...
amazing
Awful
Exam is Monday
Havenāt finished content
Coulda finished it like last month if we locked in
Instead we did push ups
Always be grateful
macro/micro are senior classes at my school so thats a future me problem
Bc got done earlier this week but Iām behind
So I still gotta learn the hard stuff
My physics class has been done but she lowkey js neglected to teach some stuffā¦
oop
Nah itās fine tho Iām gonna get a 6
lol
skull
Lets say that we have time and position axes, and we plot the movement of a fly, so it's random data, now let $f : t \to p$, so is $f$ a perfectly defined function?
Ujjawal Gupta
I assume you meant to ask this:
\begin{tcolorbox}
Suppose we plot the movement of a fly on a coordinate system with time $(t)$ and position $(p)$ axes. If we define a mapping $f$ from time to position ($f:t \to p$), is $f$ a well-defined function?
\end{tcolorbox}
\vspace{0.3cm}
In this case, the answer is yes. Recall a function is well-defined if every input from its domain maps to \textit{exactly} one unique output. A physical object can cannot be in multiple places simultaneously but still must exist, so the fly occupies exactly one specific $p$ at any given time $t$.
Civil Service Pigeon
Yes, but we don't have a mathematical expression to define random data right? So how f is well defined?
$f(t)$ is simply the physical position of the fly at time $t$, as you said. A function doesn't have to possess some neat, explicit algebraic equation like $f(t)=t^2+3$ to be valid. As I said earlier, a function is strictly defined as any rule or mapping that assigns exactly one output to every input. So the rule doesn't have to be an equation, but can also be an empirical data set, a lookup table, or just physical reality. For example, if the fly was at the point coordinates $(2,4,1)$ at time $t=5$, then you'd simply have $f(5)=(2,4,1)$. \
Tldr: The reality of the fly's location \textit{is} the function.
Civil Service Pigeon
Didn't know that, cool

Btw $f(5) = (2,4,1)$ can also be represented as $2x + 4y + z = 5$?
Ujjawal Gupta
(2,4,1) are coordinates in 3d space
Not the coefficients of a normal vector or smt
Idk where the =5 comes from in any conceptual sense
How can I represent this data as a linear equation?
You ⦠donāt? Thereās no reason why the fly has to follow a linear path.
I think youāre doing too much to escape from the abstraction to the point where itās wrong
Agreed, but these points can give linear equations ig
Which then can be solved and one can also find best solution possible through projection
Like 3 points (4,2,8), (2,4,1), (3,7,1) can be represented as $\begin{bmatrix}4 & 2 & 3 \ 2 & 4 & 7 \ 8 & 1 & 1\end{bmatrix}$?
Ujjawal Gupta
You can write 3D coordinate vectors as columns of a matrix, but this is more of an organisation tool than anything unless you're atually going to do something with the matrix. In fact, putting the coordinates in the matrix has completely dropped $t$ (the domain of your function $f$). So if you wanted to use projections to find a line or plane of best fit (that's my best possible guess for what you want, it's very unclear), you'd no longer have the corresponding times to model the movement. And again, the matrix is just an organisational tool -- it doesn't magically force a fly's highly erratic (typically non-linear flight path) into a "nice" linear system.
Civil Service Pigeon
Your guess is correct, I think projection can give a nice estimate of the fly's path through linear regression?
$t$ can also be involved as the 4th axis ig, making it an m by 4 system
Ujjawal Gupta
ehhhh idk about "nice"
Like I said, flies are famous for moving in highly erratic and non-linear paths
forcing a line/plane of best fit through that chaotic data is probably going to give you a largely meaningless trajectory
Estimate with more than 50% accuracy
Ah ok
Hello guys! Can someone help me with the "properties" of integrals?
Ohhh tanks! sorry

I need a bit help with the task below. I am just wondering - would there be infinitely many solutions for this problem?
The task:
Two planes are parallel to the xy-plane and have a distance of 6 from this plane. Find an equation and a parametric representation for each of these planes.
it may or may not help to consider the 2d version of this with lines
This would be the xz-plane: y = 0
What do you mean?
nvm
iw as tripping
i was thinking of 2 parallel lines to x = 0
Okai
Ohh
But maybe i need to first find the parametric equation for the xz-plane?
In order to find the two other planes
But if these two planes are parallel to the xz-plane, would they have the same normal vector as the normal vector to the xz-plane?
<@&286206848099549185>
yes
they don't have a fixed let's just say y intercept
like you can fix two parallel planes of distance 6, and move them about the y axis
Okai
DO NOT PING HELPERS HERE
because they still satisfy the condition, that means that there are infinite solutions
to your condition
Ohh i didnt know, i am sorry
But do i need to find the parametric equation to the xz-plane first in order to find the two other planes?
what? no
Oh okei
well what do you mean exactly
there's a really easy method with vectors and it is quite illustrative
but i'm not sure if that is applicable for your case
but if you want to like definitely prove it then sure use equations
Okei wait, so in order to find a parametric equation for the two planes i need to find a point it passes and two vectors (non-parallel vectors) that are parallel to the plane
I believe
Is Pre-Calculus just Functions and Trigonometry? Is Algebra is also involved here?
I think soo
I think it includes algebra too
it goes over algebra as well
in my class, we have these 4 units
I see
Yes
Also for parallel planes to the xy, xz or yz planes, you can simply consider simpler equations like x=c, or y=c, or z=c. And then for the xy plane you really have only two choices, a plane with points where just (x,y,z=6) or (x,y,z=-6) or shortly the planes z=±6
any other construction would either fail to be parallel to the xy axis or not have distance 6 anyway
Oh silly mee, i meant "Two planes are parallel to the xz-plane and have a distance of 6 from this plane. Find an equation and a parametric representation for each of these planes"
But i think i understand. A plane parallel to the xz-plane must also have a constant y, and in this case it can only be y = 6 or y = -6.
Yess
And the xz-plane would have this equation: y = 0
yes
yes
Two distinct lines that are parallel I suppose
Though even with one line, there would be only one plane associated with it anyway
I apologize, i meant planes not lines, so two planes that are parallel to the **xz-plane **
Then the same applies what I had said before
.
Okiee
I will try to solvee it noww
And yeah as the task says, 2 planes at most is only possible
Understood
Let mee try
Soo the equations for the two planes that are parallel to the xz-plane (the plane in the middle) would be y = 6 and y = -6
And noww i just need to find the parametric equation
yes
You can easily pick 3 points A,B and C and set up E : x = A+sAB+tAC
Since any point with y=6 for example, is just (x,6,z)
So plane y = 6 passes this point (0, 6, 0) while plane y = -6 passes this point (0, -6, 0)
Right?
Yesss
yes
And noww i need to find the direction vector. Since they are all parallel, they would all have the same direction vector, which would be (1, 0, 1), or as long as it is on the form (a, 0, b).
What do you mean by
Since they are all parallel
$l: \begin{cases} x=s\y=6\z=t\end{cases}$
dream
I think this would be correct for the plane y=6
works
you just picked (1,0,0) and (0,0,1) which are trivially perp to (0,1,0)
Well the task says that the planes are parallel to the xz-plane
Oh you meant that
Bahaha yess
Also usually planes are denoted with capital letters e.g. E
Ohh okie
$E: \begin{cases} x=s\y=6\z=t\end{cases}$
but nothing to be concerened of mathematically
dream
Like this?
I seee
Cant we use alpha as well
$\alpha$
dream
you can use any letter
any letter to your liking
Haha okiee
$\alpha: \begin{cases} x=s\y=6\z=t\end{cases}$
Ohh
Wait
fell twice for it
dream
dream
For instance
yea
Thank youuu
No problem
Guys is it encouraged to use log differentiation when approaching questions with e^x? I just started and I always use the basic chain rule and quotient rules
<@&268886789983436800> sus behavior
e^x is a special case in differentiation
Do I jsut just add a ln ?
?
e^x is the only function whose derivative is itself
Makes sense
But to solve one a derivative of a function with e^x can ln both sides?
And use log rules?
What do you mean? It depends on the assignment - for instance if you want to solve for x in this equation e^x = 2 then you can apply ln (the natural logarithm) to both sides in order to solve for x, which would give x = ln(2).
Nah letās say we have have f(x) = cos(x) plus 5x / 2x^2 * e^2x and we got to find f prime of 1. Instead of using chain rule and quotient rule can we add logs to make it simpler?
guys any book recommendations for precalc self study
Liek are u allowed to add ln to both sides in a function?
Skip pre calc, take college algebra instead
I mean just take the basics of college algebra
I donāt have pre calc in our country, but our units are functions, then calculus
Ohh
I am not suree
I dont think i have ever done that
K
Iām just horrible at differentiating
Hmm well i would recommend learning how to differentiate, because even though one is allowed to use logarithms to make it simpler or some other rules, in the end you have to differentiate i believe.
what have you tried?
I used x^3+y^3=(x+y)(x^2-xy+y^2)
Then got x^2-xy+y^2=3
you mean y^2?
Yes
okay, next?
i don't see why not
that works, but a bit overcomplicated
Iāll do elimination
just note that x^2 - xy + y^2 = x^2 + 2xy + y^2 - 3xy = (x + y)^2 - 3xy = 3
you can easily calculate xy
since you have the exact values of x + y and xy, the next steps are easy
lograthmitic differntiation in the context of implicit differentiation, for example y=x^x then applying log to get log(y)=xlog(x)
Okay
xy=1
Soo one can use logarithmic differentiation to simplify the expression?
simplify differentiation yes
Staaar
Okiee
Got it
Nooo
Not that emoji bahahaha
guys help š
for c, i know what to do, but theres too much i need to differentiate so idk what order to do
please do not ping helpers here
chain rule applies here
OMG IM SORRY
ill give you a hint
i know i need to use chain rule but ive just started trig, so im kinda confused on where to start with chain rule
$\frac{d\cos^4(5x)}{dx} = \frac{d\cos^4(5x)}{d\cos(5x)}\times \frac{d\cos(5x)}{d(5x)}\times \frac{d(5x)}{dx}$
Annie Maqionde
- power of the function
- look at the argument, you have the form for derviative of cos y, right?
- argument w.r.t. x
Do you know chain rule?
yes
Use that
but dont i have to derive the cos too?
You have to do this much
so would it come to 60 cos^3(5x)?
I thought this is graphing
You have to keep doing it until the derivative becomes 1
no it asked to find the derivatives with respect to x
Basically derivative of cos(5x) and multiply with derivative of cos^4(5x).
Ok
i feel like i did these wrong
OHHHHH
wait lemme retry
That explanation written by Annie was correct, but quite long.
And do not forget the constant 3.
no this is calculus work
i really dont understand this
ummm try to think of it like
double chain rule? i think
this is what i got from doing chain rule
but not double
idk if double is the right word exactly
like when u do chain the first time
you take the inner function as cos5x
yeah
D/dx is just apply derivatives.
and u have to differentiate the inner function for the chain rule right? well the inner function's derivative is found with the chain rule
No that is wrong.
for d/dx(cos5x) basically the outer function cos x and inner 5x
wouldnt derivative of cos(5x) be -sin(5x)?
not quite
remember the inner function is 5x
what is the final answer so i can try figure out how to get there
Differentiate the inside
your answer is very close ||if you do want a hint, the coefficient of the answer is -60||
think about how to apply chain rule to d/dx(cos(5x))... the inside... the outside...
Yeah
If use try integrating sin5x you wouldn't get cos5x right?
oh this is the precalc channel..
LOL
fah i just remembered i have ap classroom work
for precal
š„ im sure i can speedrun like half of a practice exam
hopefully you're not too confused, if u need more help ill try to answer ur questions while i speedrun my own hw
What do u learn?
š„
cus of the ap exam its just practice exams now. im in precal so its easy but its a bit tedious
I love no claculator yay
xd
OMG I THINK I GOT IT
I do love mental math
im gonna crash out if i make one more algebraic error on frq4
What's FRQ?
is it because of the -sin() from the derivative of cos()
when u do chain rule
u multiply by teh derivative of the inside function
the isnide function is 5x
d/dx(5x)=5
5*-sin(5x)
d/dx(cos5x)=-5sin(5x)
mmhm, remember the negative sign
rest of it looks good
thank you
like this is our frq 4 (but this one doesn't really have word problems its just solving)
you're welcome, glad to help ^.^
time to grind this take home practicce exam calc mcq igs
if theres a coefficient inside the sin() does that count as another different function?
I love calculus so much
yes
outer function as sin(x) and inner function as (whatever it is inside sin)
cuz the next question is y=(sin 3x)(1 - 2 cos x)
ah
i hate precallll ackkkk
when deriving sin(3x) would it be 3cos(3x)?
Yes
thanks
similar to the 5x one, you take derivative of 3x as 3 and multiply
yeha
wait i have a possibly silly question how do i know the concavity
double derivative
like after i graph is there a way to find inflection points cus i can't find a way in desmos and my calculator is lowkgenuinely dead
errr i dont think my precalc teacher would like that
im not too keen of that idea either cus with the 2pi/365(t+15) i think thatd be chain rule
but i dont really know any other way to find concavity other than double der
idk either
š
maybe i just plug in at 299 and 301 and see if its increasing or decreasing, then guess with a 50/50
well its a decreasing function at 300 so theres that
I mean u can graph it lol
oops
if u dont wanna do double deriv
ya but how do i find concavity from there
i have it graphed in desmos cus thats how i was looking at it at 300 but
Function is not that complicated if u look at the qn
if the double der is negative, its like a sad face/decreasing and positive is happy face/increasing
just at 300 is it decreasing or increasing
š
ye ik the double derivative test
if u graph
sorry
lowk dont remember if they taught us this in 9th
i just feel like my precalc teacher will chew me out if she sees me doing that (cus we have to submit our work :c)
im in 9th š„
Bro is a fast learner 
thx
NINTH?
ykw what looks concave up imma call it a day and move on š„
bro im in 12th and we just started ts š
ye
Wut
im teaching myself calc
Derivative is year 10
but im in precal
varies
here at my school
precal is standard 12th
11th advanced
Same
10th advanced honors
Interesting
but im in the US so my classmates are slow tbf
The word "US" explained it all
and the advanced honors track is calc in 11th
so we're going into expos and trig calculus
no
just normal differentiation
and the first thing we did in year 12 was double derivatives
ic ic
im graduating in october
my school has like calc ab and bc
I think we did calc 3 senior yr
oh wow
bro this math test is on friday and i cant even do simple shi š im so cooked
š„ nunu u got this
just remember like the basic derivative rules and such
grind any practice problems u find š„
š i got math finals tuesday, wednesday, friday. and then ap exam on tuesday and then my math teacher said shes gonna make us learn calc until june
i didnt go to school today (mostly because i overslept my alarm) so i can study for this
Its okay we will help u
i missed one day of math class which happened to be when we learned polar
am i getting somewhere
2nd derivative is wrong
i rearranged it to be easier for my brain so i wrote -2cosx+1
nothing
Yes
Not until complex polar
right but when you d/dx(-2cosx+1) the 1 shouldn't remain, its like if you were differentiating -2x+1 you'd say its -2 whether or not you have 1-2x or -2x+1, not that the one matters or that the placement matters
how would i multiply cos3x with cosx
just leave it as cos3xcosx
or well -6cos3xcosx
Need help with logarithms?
er...not really
but im confused on um
k(x)
is it supposed to be like
1-cos^2x/cos^2x instead of tan^2x and such or like
It said cosine appears once only
oops nvm
could i rewrite it as like
1/(cos^2(x))
Factor?
idk i take that step back, idk why i did that lol
idk what to do after simplifying it
i think its right on the second line
yeah i know, ignore the 3rd
Would this be correct?
Ummm my approach was
Csc^2-cot^2 is 1
Tan^2x is sec^2x -1
Sec^2x is 1/cos^2x
Idk if thatās right tho
lwkgenuinely im bouta just hop on brawl stars trig work is kinda ragebaiting me
No way
erm
bro i gave up, im palying roblox
Fr bro math can go crawl in a hole
Everyone lazy rn
Absolutelyyyy
And I still have math finals to study for but who cares
the academic stress isnt worrying me, whats worrying me is how im straight up ignoring it
š
š
Then lock in man stop playing lmao
š„
no its like physically impossible
i can not lock in
nunu u can do it (says while continuing to grind brawl stars)
LOL
chat?
uh
y' should be the slope
then calculate how much um... y intercept? to add
i think..
Ez
but if m is 2cosx and the equation would be y=mx+c wouldnt it be y=2cosx(x) + c?
it says
calculate the equation of the tangent
at x=pi/3
so we want the specific slope at pi/3
so we need to plug in for that
2cos(pi/3) = m
if you think about it
2cos(pi/3) = 1
2sin(pi/3) is
sqrt3
right?
and right now with a slope of 1
what would the tangent line evaluate to at pi/3?
before adding a intercept
don't overthink it
is brawl stars fun
i like it
i used to like it
pi/3?
yup
cus rn we have basically y=x
so the difference between the values of sin(x) and y=x
would be... (dont need to simplify)
another helper ping
0?
ah...
well
if you have 2sin(pi/3) as sqrt3
and y=x at pi/3 as pi/3
whats the amount you need to add to make the tangent line go up to touch the curve?
as you can see we want the line to move up a certain distance to touch the graph
(btw, 1.73... number is sqrt3)
so that distancce
is sqrt3 - pi/3
as such
sorry idrk how to explain it
back to brawl
gl... the second pic above is my final answer with the tangent line so igs u can look at that
Can anyone help me on this question? Im not good at matricies or vectors so its confusing.
What is this š„
take r as a column matrix of (x y z) and then multiply the matrices to get the equations of plane and the line
and the angle between a plane and a line is the angle between the normal of the plane and the line
thanks for the help!
no way this is precalc
Bro what the hell is this how do I even approach thisššš»
As someone who is just starting precalc this is terrifying
It actually dosent have any calculus in it
It's arithmetic but clunky
Lagrange interpolation formula
and here i am taking precalc 12 in canada where the worst thing i would see is trig
š„
chatgpt says its infinite
It is
yeah bc of lagrange interpolation, whatever the flippers that is
Whats that
-1/12
now who is pinging me in PRECALC/
substitute a = e^(loga)
i have not studied logarithms so i guess i wont get it
have not??
then i think it is time to study logarithms ig
ye its just a ton of products
take the natural logarithm of y=a^x
that gives us lny=lna^x=xlna which gives us lny=xlna
now I'm pretty sure this is implicit differentiation(same thing basically) but you find y'(same thing as dy/dx) after multiplying, this is also basically chain rule as y is a function of x and y' is the derivative
so this gives us: y'/y=lna
which can then be done as y'=lna * y=lna * (a^x)
in case you're wondering what a logarithm is
ionknow
Yes
Asking the actual question right away is more likely to get responses.
Asking "Can I ask...?" or "Does anyone know about...?" doesn't give people enough information to decide whether they can help, and answering can feel like a promise to help with the actual question, which they might find themselves unable to.
You need to write and do somethig like this:
$$a^x = e^{(ln(a))^x} = e^{x ln(a)} $$
$$\frac{d}{dx}[a^x] = \frac{d}{dx} [e^{x ln(a)}]$$
text book
e an ln are inverses and that is why that works
and then you use the chain rule
since its not in the standard e^x form
also if you don't know your logs and ln's then you shouldn't be doing calculus at all
they are quite simple though
yea h they are im just learning deravatives rn log is my next topic
Tf
Logarithms should be taught before differential calculus
idk ill learn it
in next class (lecture)
shouldn't differential calculus and integration be taught first , bc ln(x) is the integral of 1/x
are they? or are they a completely diff thing im confused
Like log with a base of 2 with argument 8 is basically saying
2 to what power js 8
oh ye
i geddit
Thatās the opposite of 2 to the power of 3 is 8
but expo was before log or was log before expo
So log is an operation that can undo exponents. like multiplying and dividing
Wdym by before?
i see
like which came first in discovery or were they found together
and later differentiated
Exponents I believe logs were calculated
i see thats what i felt would be
was logs discovered to counter issues of math in which alg cant enter?
Actually idk if exponents were first but yeah people would like publish log tables to solve problems
hm
yes
Iām not sure when the calculus implementation of exponents and logs was tho
exponents should be before because they come naturally not saying log is artificial but exponents are moe out there in human and space logic than log
could be when calculus branched into things where alg couldnt enter?
Probably
Idrk math history
Exponents have 2 inverses
Roots and logarithms
No
They do different things
You can't compare them, they're used for different scenarios
hi
Can you do factor with x^pi =1
Idts
it appears that while basic facts about exponents were known since antiquity, the modern concept of an exponential function and its derivative didnāt come until after people noticed the area under a hyperbola is related to logarithm tables.
Napier/Briggs: logarithms as computational tools
Saint-Vincent/Sarasa: natural log as hyperbola area
Newton/Leibniz: calculus makes d/dx[ln x] = 1/x
Bernoulli/Euler: e, exponentials, inverse-function viewpoint, and d/dx[e^x] = e^x
the thing is it took a long time for people to formalize what a function is and what should count as a function
hmm i see, interesting
Alright
As these quantities were more radical?
I'm not sure what you mean
but something like $2^{\pi}$ took a while for people to come to grips with
ManifoldCuriosity
or $\sqrt{2}^\pi$
ManifoldCuriosity
yo guys, what on earth is Limit?
a limit defines what a function approaches at some x value
also one sided limit, from the left/right
alright thanks
but that's not quite what I am lookin for
what are you looking for...?
oh, so that's not the question to be asked in this chat
I'll go to calc chat
if there's such
there is one, I think it's fine to ask here though
I'm not quite sure what you mean about where limit comes from
do you mean what motivates the concept of limit?
my teahcer taught us diff quotient in the first week of school š„
in precalc?
ye
nay, what I am asking is the formal definition of Limit
that's tuff bro
<@&268886789983436800>
it was kinda silly tho cus the kid next to me was like rlly confused
bcs
so many ppl asking about calc 1
the video we watched said f(x) and our worksheet used g(x) and they told me "its not the same function" with a straight face
why they say that?
probably because they didn't have good enough foundations to understand that f(x) is just a name for a function..
of course they're not the same
ah, sure. Well there are a couple types. There's limit of a sequence of real numbers, and there's limit of a function f(x) as x -> a or x -> infinity. It also looks a little different if the value of the limit is infinity
seem about right
they were a senior btw like a full grown adult with a mustache
the formal definition of the limit is
if f(x)=x² and g(x)=x³, they're different functions
not like that
it was a formula
yeah, that's the case of a function limit, with the variable approaching a finite number, and the value being finite
which used f(x) as an example
and the worksheet had us calculate it with a function g(x)
i think what @undone pumice was talking about was two functions that have the same set of input numbers and output numbers
like f(x) = x^2 and g(x) = x^2