#precalculus
1 messages Ā· Page 98 of 1
Yes
Oh okie so power rule !
I know basic formulas...
I rather need techniques..
Like they transform the whole integral to something š
you mean indefinite integrals?
i know, did u see what i said in #competition-math lol
and i didnt say it was impossible, just not really doable by normal methods
Do they have period and amplitude
Mm yea
that means what was your original eqn
Calculas is the EASY CHAPTER
"Reciprocals" is even better.
Are linear algebra concepts like linear transformations usually taught in precalculus?
Depends on where you learn it
Ah, because I'm learning it on Khan Academy and they not only do vectors and what a matrix is (and how to solve systems of equations), but they're doing linear transformations.
It's like an "intro to linear algebra" course in a way, even if it's in precalculus.
its precalculus
i got same in precalc book
yeah..cuz its precalc
<@&268886789983436800>
I did was
Is there is amplitude in front of csc/sec x
Make a guide graph of sin/cos x
Place them there and draw asymptotes or poles
And draw āparabolaā
Check my work
Mine got skewed
i dont like this wording, the pole is the x axis... you dont draw them
I was told to draw the asymptote
O
ye... draw the asymptote, not "poles".
Okay
looks good... i think
do u need help?
Iāll show u
Now I have period of pi and quarter period of pi/4
And then Horizontal shift is none
Where to start
yup (but remember that the period is over 2 set of asymptotes)
0? then pi/4
Yes
I graph the cos 2x as a guide graph
based on that, where are the asymptotes?
pi/4 and 3pi/4
yup
Is it true that if I graph
ye
I start with the horizontal shift
it touches so its useful to draw the cosine
Then add quarter period
uh i dont know
i never learned all this quarter period bs
i just learned how to graph
Period/4
Where do u start
csc or sec x
Evelyn what are some advice about graphing tan and cot
uh
Since Iām learning that tmr
they look very similar just reflected versions moved differently
like
cot looks like tan
if it was reflected over the y axis
It itās sin x over cos x
and it was shifted pi/2 (cus cot=cos/sin and sin has diff zeroes)
0 1 0 -1 0
1 0 1 0 1
0 und 0 und 0
ye there will be asymptotes
period of pi
and then
pi/4 and its other angles are useful(cus tanpi/4 is just 1, right?)
the main I use is
so you can use 1, -1 for tan from -pi/4, pi/4
0, pi/2, pi, 3pi/2, and 2pi
Asymptotes of tan will be at pi/2 and 3pi/2
Itās asymptote of tan = (odd number)*(pi/2)
this is... an unusual way to put this
also 5pi/2, 7pi/2, 9pi/2
my teacher taught us using
Then I did
Quarter period = period/4 or 1/4 * (period)
My teacher also wrote it that way
mm k
mm ic
so period shift but no horizontal dilation
vertical dilation
no vertical shift
Do I start at pi/4
wdym by that
Im a 9th grader
And i came across this equation of making a heart shape
(X^2+y^2-1)^3 - x^2y^3=0
And i was wondering whether integrating from 0 to x and 0 to y will completely fill it up?
Im trying to learn all this and i think this is how you do it so can someone please explain it to me
do you have a diagram?
no first you must draw the function and
find its range
as shown the range is from -1 to 1
its possible but its not for this channel
Integrate from 0 to 1?
its very complex
you have to make the function to only have x
otherwise it wouldnt be possible
Why cant we integrate both x and y
thats to find like volumes and stuff
you need to intergrals then
which is very hard to do
so all you need to do is to make this equation into a function with y being the subject
and then intergrate it from -1 to 1
sqrt(x) does the limit exist at 0 ?
pretty sure sqrt(0) itself exists
Yes, but some textbooks only define limits for functions that exist in an entire deleted neighborhood of the target point.
That's not any kind of deeper mathematical truth, though, only an attempt to save complexity because it takes a bit more explanation and notation to define them more generally..
What? Where?
Your equation does not define a function, as Cdkkpoke's plot shows, so it does not make sense to integrate it.
Yes, $\lim_{x\to 0} \sqrt{x}$ exists and is $0$, but some textbooks give simplified definitions that doesn't work in this case because $\sqrt{x}$ does not exist to the left of $0$.
Troposphere
Writing f(x) = (x^2+y^2-1)^3 - x^2y^3=0 would not make sense, because what you put to the right of "f(x) =" should be an expression rather than an equation.
You can write f(x) = (x^2+y^2-1)^3 - x^2y^3, but that still doesn't give you a function until you decide on a value for y.
You can write f(x,y) = (x^2+y^2-1)^3 - x^2y^3, but (a) that now is somewhat far removed from your heart-shaped curve, and (b) integrating a function of two variables is not a single thing -- that is there are several possible concepts it could mean.
Oh
So if we find an expression that gives us the heart shaped curve IN THAT X VARIABLE, then we can integrate it from 0 to x, filling the shape up?
It's also not quite clear to me what you mean by "filling the shape up".
I suspect perhaps instead of integration what you want might just be the inequality (x^2+y^2-1)^3 - x^2y^3 <= 0, which makes the solution set include the interior of the heart.
Or are you trying to compute the area of the heart shape?
I was maybe thinking of the same shape but a tiny width smaller than the last all the way until 0, which would make it not only 1 heart shape but "filled up" in the sense that it is completely coloured. And i figured that using integration could perhaps give that small width needed to complete the fill up?
where does number theory go?
#elementary-number-theory, or possibly #advanced-number-theory for techniques that go beyond standard undergrad topics.
Is this beyond undergrad?
No, I was replying to the other person with the weird name there.
Hes my friend from school
Yeah @hushed sphinx so my question wss
Was
Hope you understand
Is this not an answer to what you want?
It is an answer
But i want infinitesimally small hearts inscribed in each other
Like concentric circles perhaps, but with the width in between them almost 0
Okay, that is definitely not something where the concept of "integration" is relevant.
Oh, okay. Could you tell me how to do that though?
Wow
You can get a family of curves that fill out the heart by setting the right-hand side of the equation to different negative values instead of 0. However, as this plot shows, they behave somewhat wonkily around the axis crossings -- In fact, I don't completely understand how the original manages to look nice and smooth around the x-axis crossing.
I don't immediately know how one would create neat equations for curves at a constant distance from the heart shape. That is in general a hard problem that cannot be done with polynomials.
bro you drew mickey mouse
Would anyone perchance know how to find the focus of a parabola?
What do you already know about the parabola? Equation, or some points on it, or a drawing in the plane and you have straightedge and compass?
is the parabola aligned to an axis?
well my course book says that limit exists if left hand limit = right hand limit.. but in this case since LHL doesn't exist so I'm a little confused
Yeah, that's one of the "simplified definition" patterns I'm talking about.
I see.. then what would be the absolute definition ?
It would be something like the limit of f(x) for x->c is a number L such that
for every epsilon>0 there exists a delta>0 such that for each x with 0<|x-c|<delta and f(x) defined we have |f(x)-L|<epsilon.
and then with a caveat that the concept doesn't make sense (because L would not be unique) unless c is a limit point of the domain of f.
hm.. i see
thanks for helping
Hey I need help for doing y=-5 cot 8x
Amp: None
Period: pi/8
Quarter point: pi/32
Vertical shift: none
Horizontal shift:none
Or in fancier topological terms: "the preimage of every neighborhood of L is a (deleted) neighborhood of c, intersected with the domain of f".
I need help graphing
If 7x+2y=4, 128^xĆ4^y=?
SAT sneaky question
Sneaky?
Yes
Wait your user/nickname is A EQUATION
Take the god damn log2 of both terms
Solve without logs. Solve with Jungle Method
Wtf is a jungle method
You realize that 128^y = 2^7y, 4^x = 2^2x?
An Approach to solve equations that can't be logged or NOT using natural/standard logs
1 that doesnt explain what it is or how it works
2 this is clearly loggable
And standard logs?
Log(4)(2)
Fyn standard
What do you mean by that?
Standard means the classic log in precalculus

You know logs arent constrained to base 10 or base e right
I meant
Standard Logs: Log_4(5)
Natural Logs: In_4(5)
Pardon me what does the log4(5) mean?
$\log_4{5}$
ishantgaming67
Bruh
Natural Logs: In_4(5)
makes no sense
And this
We are cooked by Dagestan 2-4 years old
<@&268886789983436800> dagestan joke
It's not that bad joke as E word
But thats still homophobic, so what?
since dagestan is a muslim region, they are homophobic there, getting send to dagestan implies you are going to get the gay beaten out of you
Please be more mindful of what you post for reasons mentioned above.
u r not real
Fym not real
You know plenty of memes out there are in fact bigoted
Sybau
You mean
If 7x+2y=4, 128^x * 4^y=?
Easy
128^x = 2^(7x)
4^y = 2^(2y)
2^(7x) * 2 (2y)
2^(7x+2y)
2^4 ; (7x+2y)=4
128^x * 4^y = 16
This
Ye
You use exponents properties of
a^m * a^n = a^(m+n)
Yup
Idk what that guy was up to tho with the log_4 shit
And wth is a jungle method
Vro never explained that
Can you check this please
^
Do I graph like this
Please recheck your amplitude and period Remember the general structure for cosine is a*cos(k(x-d))+c.
Itās not cos itās cot
Right
I thought it was cosine, sorry then this is correct
for the second one i do not know about how your teacher structures things however I believe its more preferable to say pi/6 right rather than -pi/6 and for VS it is 1 unit up. But that is just communication other than that everything checks out and is correct.
Okay
Then itās pi/6 + the quarter period
That should be where the next increment is located. the period + quater period , then plugging that in will give you the y
I thought I start the HS + quarter period
HS ± quarter-period gives you the key points for one full cycle (the one you actually sketch). Adding the period just moves you into the next repeated cycle, it gives the same type of points, just shifted right.
I started with pi/6 and add pi/8?
Then itās 14pi/48?
Well, that will give you the first quarter-period point of the cycle. You can also subtract Ļ/8 to get the symmetric one on the left.
Ok
So is that the asymptote
Thatās what I got so far
No that is not the asymptote that is the important points where the tangent hits a specific y value after the transformation the asymptote is at x = -pi/12 and 5pi/12
Almost, you have to solve when the inside of the tan is equal +- pi/2
So solve 2(x-pi/6) = pi/2
that will give one of the asymptote
the general is 2(x-pi/6) = pi/2 +k*pi
Okay
x-pi/6 = pi/4
x=pi/6 + pi/4
x=10pi/24
x=5pi/12
Donāt laughs at my sketch
Why is it broken like this
I didnāt have a steady hands
Thatās why
No worries there
But is that right
That is correct that is one of the asymptotes
Yay
And other than the drawing the tangent graph seems correct
Okay
I think graphing trig functions are interesting
Like doing sec and csc
Itās like a parabola
And cot is like cubic
Well cot is -\tan\left(x-\frac{\pi}{2}\right)
-tan(x-pi/2) for cot(x)
So especially the identites they are interesting and can aid later on in more higher mathematical sectors as they help simplify many equations.
Yep
Can someone give me some basic limits questions (infinity included) (please donāt include cubes conjugates and trig Iām trash in them)
Here are some basic ones without trig, conjugates, or cubes
-
lim x->2 (3x+1)
-
lim x->4 (x^2 - 16)/(x - 4)
-
lim x->3 (x^2 - 9)/(x - 3)
-
lim x->-1 (x^2 + 3x + 2)/(x + 1)
-
lim x->0 (5x)/(x + 2)
-
lim x->infinity (2x + 1)/(x + 4)
-
lim x->infinity (3x^2 + 2x)/(x^2 - 5)
-
lim x->infinity (4x + 7)/(2x^2 + 1)
-
lim x->infinity (5x^2 - 1)/(x + 3)
-
lim x->0+ 1/x
-
lim x->0- 1/x
-
lim x->2 1/(x - 2)^2
-
lim x->2+ 1/(x - 2)
-
lim x->2- 1/(x - 2)
-
lim x->infinity (7 - 3x)/(2x + 5)
š
Civil Service Pigeon
Ty
Iāll save it with myself
lim x->4 of 5 is crazy
Also lim x-) 8 (7)
And what is 7
sqrt(6)
$\lim_{x \rightarrow -1} \sqrt{x^2+5}$
P(this user is larp larp) ā„ 0
Jake
$\lim_{x \rightarrow -1} \sqrt{x^2+5}$=$sqrt{(-1)^2+5}$=$\lim_{x \rightarrow -1} \sqrt{6}$
Look
Chop the limit off in the second step
Since you are substituting x in anyways
Can you show me please
Jake
$\lim_{x \rightarrow -1} \sqrt{x^2+5}$ \
Substituting x = -1 in we have \
$\sqrt{(-1)^2+5} = \sqrt{6}$
Thanks
P(this user is larp larp) ā„ 0
Cmon guys y'all can solve ur questions š„
uhh well if we rearrange and divide by x we can see that x=2 is a solution
there has to be a second one too by ivt
How do u use lambert w function
uhhh
(x^x)/x = 2 for the integer solution. then for the other solution
take the natural log
but im pretty sure its um
a transcedental equation
from my knowledge
x^x=2x
x=log_x 2x
Uhhh yeah so it ended up as like a transcedental equation type situation
where you can't reallllyyyy algebraically solve it
lambert w
Then the only way is to plug and check
Ik exponential functionsās domain is x>0
*x>0
I plug 2
(2)^2 - 2 =2
2=2
Idk whatās their exact form of 0.34632
evelyn \\ HS 9
i would do like substitituion maybe
cus lambert w wants ue^u structure
so like maybe if u = lnx
(e^u)(e^u-1)= e^(ue^u-u)=2
$e^{\left(ue^{u}-u\right)}=2$
evelyn \\ HS 9
hmm
haven't heard of that one before
rn im attempting to force this silly equation to be a lambert
i don't think that's possible cuz it becomes (x-1)lnx=ln2
wait i think i got it i managed to squish it into the form where the solutions are 1/W(ln2) and 1/W subsript -1(x) ykw for the branch index of ln2
huh how
nvm i have dinner
1/x-1
ah seeya
a bunch of substitution work and stuff mostly just weird manipulation
hmm
(ts is not fitting on the small paper i have-) okay so basically first i substituted y=lnx which gave (e^ye^y)-1=2 or e^ye^y-y=2
alr
y(e^y-1)=ln(2)
u(1-e^u)=-e^uln(2)?
uhhh ye
i wrote it like that
then isolate the u
so add ue^u to both sides
ok
Lwk my Chromebook just died but hereās the next few steps
I didnāt know what letter to pick so uh ye I substuted in an a
After more manipulation got it into ae^a form which is lambert w
And then from the first substitution y=lnx it got kinda squished in the corner but
ok gimme a sec to read over this
Kk if I made a mistake lmk lwk tried like four approaches until I got a lambert form š„
so u tried to apply the lambert w to a*e^a=a/2+ln2/2?
there's a linear factor in the RHS
wait
so i tried back-subbing the final value in and it didn't check out
For this case yeah
In the future you may want to be more careful about mixing signs on your shift
Using āleftā/ārightā also works
It goes right pi/2
Ohh
Hence why I said it was fine in this case even though you mixed negatives and positives
Bc these are also a point
For graphing
My teacher wants us to make Horizontal shifts the same denominator as the Quarter period
Thatās not what Iām talking about
Iām talking about how you wrote a negative and dropped it
Oh yea
I shouldāve wrote āleftā
Do I add pi/4
adding pi/4 to what
pi/4 + 2pi/4
Is that right
um I mean you can add anything you want to
What are you trying to accomplish
Iām not following
I want the next point
uh ok ig yeah
the amplitude is not "none" its 1
Tan has no amplitude
oh yeah
whoops
for adding points to the graph. ecspecially with tan where its a bit wonky, plot the asymptotes first and then the x intercepts. and then the rest of the graph doesnt have to be exact just follow the shape of the function
so pi/2 is an x- intercept but so is pi/2 +kpi (k belonging to intergers), so you need to plot (pi/2, 0) but also anyother x intercepts that fall into the graphs domain
and then draw the behaviour around the nearby asymptotes
Itās x-pi/2
So is it (pi/2,0) the point
Iām trying to add quarter points easier so I made the HS 2pi/4
yeah so every x- intercept on this graph is in the form (pi/2 +kpi , 0) letting k = 0 gives us our 'first' x intercept at (pi/2, 0)
Ok
whats HS sorry?
no like what does it stand for ?
Horizontal shifts
oh okay
yeah i mean if it works then sure, but looking at the graph you have above i would make the far right line pi (vertical asymptote) the middle line (on positive x axis) make pi/2 (x intercept), the zero line is just another vert asymptote and then do the negative
you dont really need to split it into quarter points
*right pi/2, not left. graph will look the same i beelive for left or right but...
Oh and also yeah. If the zeroes of the parent tangent function are -pi/2, pi/2, 3pi/2, shifting pi/2 right just makes it like 0, pi, etc
and again you dont need the quarter points, they dont really add much, since they dont show anything special about the graph
make sure to label your vertical asymptotes with the equation of the asymptote as well
yeah or just give the equation of the general placement of the asymptotes (like the set theory notation i showed u)
this ^^, also along with that if you do have working out on the side, right the set theory for the x intercepts as well
which in this case would be x=0/pi/2pi/whatever starting point + pi k (or n, or whatever variable you want) where it is defined as an integer...
My teacher requires it
*right pi/2. graph looks the same right or left but if you want to get technical its shifted to the right pi/2 and if you're being graded on whether you wrote the right direction..
wait one more thing
3pi/2 is not in the middle of 0 and pi
label that one as pi/2
from that it looks like you have a vertical asymptote at 3pi/2, your behaviour of your graph around asymptotes needs to be shown (bring the line closer to the pi)
^^ yup what i was saying, move the "zero" to that mark and label it as pi/2
that is also incorrect
it crosses at the point in between 0 and pi
which would be where you have marked 3pi/2, which is incorrect (redraw your graph, and also relabel)
... well i guess that works too
technically right but the more correct way to write this is pi/2 +kpi (k belonging to intergers) or if you are really adament with that odd number write it as (2k+1)pi/2 (k beloginging to intergers)
and just search up the math symbol and set notation for beloging to intergers
its like a weird E into curly brackets
..... glad to see it stuck
Sigh
Graphing trig functions that aren't sin and cos š¤¢
techincally you are just graphing both :D.
i guess bro š
Yes
How do u do no8? I did dy/dx to get the negative reciprocal for the normal gradient
I was taught
Graphing sin and cos
Graphing csc and sec
Then
Graphing tan and cot
#calculus but hereās my solution anyway
4^x=x?
Yup
Is it correct?
|S| : number of elements in S
What's correct for $|S \cross S|$?
Ujjawal Gupta
How?
Err
In that one example
S has 2 elements
There is like 4 ways to pair 2 elements together
So 2^2
What if it has n elements?
Then S^2 has n^2 i think
(Looking at it, its nicely related to pascals triangle too)
Should I use the quadratic formula to solve for x in quadratic equations?
Yes
Like
Its literally made for that
lmaoooooo
Absolutely not! You should use it only to solve 16th degree equations
Try it in Desmos
Y=the equation, Y=X
What
Desmos
Err
The lambert W function extends to complex solutions too
Desmos cant do that
Yeah but like, aren't there faster ways?
Yes, its called factoring
But almost all quadratics are not factorable
Really
Yes
Is there a way to solve x^x=a without using lambert w?
Cause im not really accoustumed to using lambert w so im really unsure if what i did was correct or if there was a better way
That's pretty much what the W function is (up to some logarithms).
However, you may count numerical methods (such as bisection) for root finding as "a way to solve".
That's how the W function itself is computed, anyway.
I understand,thanks.
,w
Desmos will show an exponential y that grows fast
Err you are clearly not understanding what i meant
Note that
$$\frac{1}{5+\sqrt{24}}=5-\sqrt{24}.$$
Civil Service Pigeon
well yes those two work, but I'm assuming you want a fully rigorous solution to show that there's no more
I wonder how
I thought itās (5+sqrt(24))^-1
Yes, it's that as well
If Iām correct
Itās -2<x>2
As its domain
I don't follow
Both terms on the left are exponential functions with positive base
meaning that both terms on the left are defined for all real x
Okay
When I graphed it it looks like a parabola
But with discriminate > 0
Yeah that's how a^x + a^(-x) usually looks:
but it's not really a parabola
,w graph cosh x
Rather it's a transformed version of the cosh graph (I'll let you figure out the actual transformations)
$$\cosh x=\frac{e^x+e^{-x}}{2}$$
Civil Service Pigeon
Ik (1+1/x)^x=e
the limit of that is e, yes
what does the h mean?
hyperbolic cosine
Yeah that's how the hyperbolic functions are notated. So sinh is hyperbolic sine, tanh is hyperbolic tangent, etc.
i think hyperbolic trig is a little outside precalc level though
I agree
eh it's just linear combinations of exponentials which they should be familiar with, no?
so it should be fine up to the one piece of new terminology
Cuz I just got to graphing tan and cot
though the hyperbola background is a whole rabbit hole of its own
and proving that representation is definitely outside precalculus level but itās nice to know
oh what do those look like? i haven't worked with those before, only like regular hyperbolas and ellipses and stuff
i only know that cosh creates catenaries which show up in hanging chain problems
other than that you can graph them but i'm not aware of any special names for them
also here's why that equation is true
Ohhh
Taking their conjugates
And difference of squares
really useful for systematically solving the original problem
since of course that means you can represent one of the terms as the other term raised to the -1
am i able to learn pre without understanding algebra that well
precal is kinda a lot of alg review so ummm like
i would sayyyy its possible buttt i would not recommend it if you can take some time to review like alg2 stuff over summer or something like
ye
ah
I meant to do 4 tick marks
aint no one tryna graph trig functions anymore
I would
Good luck graphing them
i always hated graphing in precalc and alg2
i mean i could do them but it was just tedious and annoying
š„ the graph isn't even labeled properly
So just use white and cover them
ik... but like...
the period is still pi so it shouldn't be in units of 1, 2, 3, 4 ...
i mean its not that bad
ill go graph it rq will see how long it takes
labeling with integers when doing trig funcs is so nasty š¤£
exactlyyy
kinda hard but just imagine at -pi/4, -3pi/4, pi/4, 3pi/4 the y is 1/3, cus its hard to make it look like that
i dont miss that shit one bit gang
š„ my teacher made us graph em too
like last month
this is actually left pi/2
and you didn't shift it
the asymptotoes of parent tangent are at -pi/2 and pi/2
so when its shifted its supposed to move
and tangent is strictly increasing in between asymptotes
Is it pi and 0
yea
^^ i drew mines up here if u wanna see (mine is more stretched out but)
I was look at this
thats cotangent
cotangent as i mentioned before looks like tangent but reflected horizontally and has different asymptotes
for the cot or the tan graph
yes
dont get me started
it'd be like 24 and 2 or something
and my teacher made us guess and check every value with synthetic division
not in precal tho
teach gave us a 6th degree poly and told us factor it, the constant term as a 24 or something that had a bunch of options
in that other course, integrated 2
š„ rrt made me hate numbers like 24 like wym this number has so many factors
couldn't have been 20 or something
fr
Yes
I got that too
I love rat theorem
used it like twice ever
š„ its js annoying
for me
ts pmo
glad we didin't use it this year at least
i was taught like some rules that helped eliminate certain terms but i forgot them all
same here
My teacher used desmos
Which made it quicker
Get the two roots
Choose one do synthetic
And done
lucky
we had to just
guess
no calculator allowed
we were only ever allowed scientific calcs, never graphing
you still have it written down as "right pi/2". graph looks right, make sure when you label its clear which tick mark is that value because it kinda looks like the one above where it's supposed to be
ye... not until precal were we allowed graphing
learned RRT in integrated 2 so was just like... "is x-1 a root" no its not "okay lets try x-2" going off vibes until u got one
Also that unit was the first unit in pre-calc to get an 100
why is y=1/3 1 unit above the x-axis and y=-1/3 is 2 units below
Thatās what was my question
they should be the same distance from the x-axis though assuming your scale represents each unit as a change of 1/3
yo so like im working on sigmas but im lowkey clueless on how to find these darn formulas
i mean like it gives me a series or sequence and the answer key has something completely different than what i put
systematic solution
||rearrange: k^3-k^2+36=0. rational root theorem: roots could be ±1, ±2, ±3, ±4, ±6, ±9, ±12, ±18, ±36. test them, you get -3 is a solution: (-3)^3-(-3)^2+36=0 -> -27-9+36=0 -> 0=0. so (x+3) is a root. polynomial division: (k+3)(k^2-4k+12). solve for zeros of quadratic: k= 2±2iā2||
And yes
Can anyone tutor me? I'm working on derivatives in my precalc class
isnt it -36
oh derivatives in precalc? like actual derivatives or limit definition
im in precalc too, i can try to help u
product rule, quotient rule, second derivatives, chain rule
oh wow i see
alr so which parts dont make sense
do you not understand how/when to apply the rules or is it like more you dont get the concept/intuition behind stuff
well its not that they dont make sense, I was absent last week for some personal stuff and now I have to learn the whole unit before the test tomorrow
oh i see
uhhh
so do you know the rules?
if not ill go over them and try to give u some examples
I think I got the product rule down, Im trying to learn the quotient rule atm
im just learning as I do my papers I missed
if you look at quotient rule its actually very similar to product rule
in the numerator
like if you have say f(x)/g(x) its the same thing except you have to put the derivative of f before g and theres a minus sign instead of plug
and then divide that by g(x)^2
Okay, thank you!
you're welcome
if you want more help ill be lurking here while i play some brawl stars
Okay!
make sure you do it in that order, because if you choose to do g'f - f'g it will switch the sign
for the numerator that is
It is derived from the product rule
3
And hint use difference of cubes
lim x-> 1 ((x-1)(x^2+x+1))/(x-1)
lim x-> 1 ( x^2+x+1)
(1)^2+(1)+1= lim x-> 1 3
D
Thatās my step
yeah, thats the most logical solution
I would say this is the basic of pre-calc
ts is way too easy
but for instance the kinf od limits that include recursice functions are just pure labor
our precalc class never taught limits to this degree 
wow
Also I saw one when I see lim x-) inf and the one u canāt solve take the coefficient of biggest power
we were just taught limits of polynomials as x->infinity or -infinity
nah those are eay too
well, yeah
but like did you learn undefined cases?
oh thatās just figuring out horizontal asymptotes
-x^2/x^2 = -1
Loook
graphically yes
Is this the one u learn
we did learn about continuity of a function by seeing 1. whether a limit from the left exists 2. whether a limit from the right exists 3. whether the function is defined at that point
Yea thatās what I did
but that was really early on and i donāt think anybody remembered anything about it
other than me
because itās a little more relevant in calculus
f(a) exist
lim x-> a f(x) defines
lim x-> a f(x)= f(a)
Check
so you learned partial limits
anyone open for practice?
god damn you are in a lot of gacha servers
u are in a lot of gacha servers
wanna do integrals?
i am currently going to class
yea same
but then they put it in the exam š
did you do sinx/x
i learned it on my own and i know it equals 1 but no
Hey is zero also an asymptote specially vertical
hmmm i cant tell with the hand writing on
Graphing tan function
Thatās shouldāve been
Why does this look like lambert W material
,w 49^x=9^x + 16^x
No lambert w suprisingly
i mean if you simplify it down to 3^(2x)+4^(2x)=7^(2x) you can recognize that 3+4=7 so 2x has to equal 1
Yea
I know
iām not entirely sure how you would more rigorously solve it though
Logs perhaps?
Or lambert w function but idk
i donāt know how logs would help
Yea...
But like log(x^y) = y log (x), but the damn addition term
https://docs.google.com/document/d/1wREEmT8ngiGGJGhOoUBWXcK75PYvkqeCjhlN-FhbUAQ/edit?usp=sharing
can someone do my homework
no.
why
we can only help you with the questions, not outright give you the solution or do your hw
well can u help me
whats the fastest solution
well ill just look for someone who can answer it
also this is for like #multivariable-calculus
its just a calculus with hard problem
well if you think so then go to #calculus , or read #āhow-to-get-help to get help
problem 3 and 4 uses traditional integration techniques
so can u solve it or not
no, but if you ask it in #calculus someone might be able to help you. Please note, we can only help you with solving the questions, not outright give you the solution or do your homework for you.
so u will only give out solutions if its not homework
no
we dont give out solutions in general
where did you even get that conclusion from?
hmm so this chanel doesnt give out solutions in general
this entire server*
you would know if you read #rules
How do I determine which value the foci is attached to when working with Ellipses?
Value as in x or y
the foci will always be on the major axis
in other words youāll need to determine whether the ellipse is oriented horizontally or vertically and from there you can determine where the foci are located (y for vertical, x for horizontal)
Whatās this mean
Thanks
Whatās the asymptote for parent graphs for tan x and cot x
,w asymptotes of tan x
,w asymptotes of cot x
odd way to write it but ok
$y=\tan(x)$ has asymptotes at $x=\frac{\pi}{2}+n\pi$ and $y=\cot(x)$ has asymptotes at $x=n\pi$ ($n$ is an integer.)
Civil Service Pigeon
This is immediate from noting that $\tan x=\frac{\sin x}{\cos x}$ and $\cot x=\frac{\cos x}{\sin x}$ and considering where the denominators are equal to $0$
Civil Service Pigeon
@round geyser
x=0
eh depends on how precise/colloquial you're being
"between" usually means you exclude the endpoints
And x=pi
but if you're talking about the closed interval $[0,2\pi]$, then $y=\cot x$ has vertical asymptotes at $x=0$, $x=\pi$, $x=2\pi$.
Civil Service Pigeon
If you're talking about $(0,2\pi)$, then just $x=\pi$
Since my teacher adds in quarter period
Civil Service Pigeon
And horizontal shift
I would start at horizontal shift then add in quarter period
hardest part of precalc?
wdym by this
what was/is the hardest part of precalc for you specifically
oh
uhhh
matrices?
thats an interesting one ngl
i understood most of what we learned from prior courses
and vectors and stuff
its just like... mostly cus i didn't really learn them before. having to learn stuff like unit vectors and stuff is just new and a bit hard to understand
yeah I see how, personally for me its mostly probability and statistics
oh
we aren't learnng that in our precal course
i only know like probability up to normal distributions and stuff
bell curve thingy
dam, its good because it shows how set theory becomes practical in probability
from prior course
used to be just stuff I learned for proofs
oh
that too, because it comes back up in calculus, you eventually learn why the bell curve has that formula
we only have 4 units in my class. two are more algebra ish focused, 1 is trig focused, 1 is matrices/parametric equations/vectors
mm i see
i didn't learn that in precal tho
a course called integrated math 3 that i took last yr
yeah imo statistics is like the physics of math if that makes sense, you learn just like a base foundation and then way later you build on with way more advanced stuff (calculus)
ah
my teacher told us we should take ap stats or calc next year depending on our major but i didn't really know so i js picked calc
yeah calc easily because calc is everything, calculus and linear algebra are top fucking tier, especially once you see how they are interconnected a bit, it be crazy enlightening in differential equations
I would say limits
stats is that one math subject iām never interested in whenever itās taught in classes
is limits even precalc and not calc
fair enough
i think an introductory to limits can be precalc
i feel like u just need some interesting questions
but calculus dives much more deeply into limits
right
Wrong section
Should I assume that the vectors' angles equal 0, 90, 180, and 270, respectively?
what are the vectors youāre saying have those angles?
And?
My first idea was combine from left to right
Like combine ln 3 -ln (x+5)
Info ln(3/(x+5)
Yup correct move š
Make sure, though, to check the domain of the whole equation (better if you do it at the beginning)
Yeah. If you don't like this, you can avoid that, by bringing the two negative terms to the right side
If Iām correct
Bring āln xā to ur RHS
Now is ln 3 - ln (x+5) = ln x
ln(3/(x+5)) = ln x
ln cancels
3/(x+5) = x
Will u get x^2 +5x-3=0
I like this kind of question
a=22.41(b+c)
b=0.83c
āWhat percent of b is aā can be a is what percent of b
Is that right
Yes
22.41 actually but yeah
Who tf did come up with that huge percentage lol
So, my idea is sub in 0.83c
a=22.42((0.83c)+c)
a=22.42(1.83c)
Solving for c in b=0.83c which is c=0.83/b
a=(22.42 x 1.83 x 0.83)/b
Check
Trivial if you have a calculator but would be annoying to do manually
Right
But is that right
Hi Iām a bit confused on how to take the derivative of this function (donāt know where to start) (12)
Do you agree it's a fraction, don't you? Therefore, you'll need to apply the formula for the derivative of a quotient
Yup (together with chain rule)
fyi this belongs in #calculus (if you dont have access, id:customize ) cus precal is just like alg trig limits and such. if you ever see anything inside a sqrt that would be chain
Oops sorry we learning this in precalc so I forgot š
ah. is okay! (wow ur precal class is ahead hmm..)
Help I guess it is prep for calc bc. Also thanks for reminder of chain
ah icic im only doing ab next year prolly
np
The eastward direction ones are 0, the northward direction ones are 90, etc.
chain rule, power rule, quotient rule
i think
i js did t(x) = sqrt((x³-1)/(4x²+4x+1))
and then f(x) = sqrt(x) and g(x) = (x³-1)/(4x²+4x+1) and t(x) = f(g(x))
prolly overkill tho
umm
how are your algebra and trig foundations
I got 3.0 on algebra
3.0?
yup for the smester but I slacked on the final
3.0 or B-
OH like gpa wise got it
uhhh
in my experience (im in precalc rn) precalc is just alg2 stuff with some new concepts, plus trig (unit circle and reciprocal) and that stuff, plus limits maybe
I am older student and I want to get through this to get further in my CIS degree
I see
I just bought precalc by sullivan
Ah
rewrite the numerator as (x^3 - 1)^(1/2) since a square root is a 1/2 power, then use quotient rule along with power rule and chain rule
Iām helping my friend through h algebra II and theyāre doing trig and unit circle š
Lord fang believes in me
ah
i did it in integrated 3 at my school
well not at mu school in middle school but ye
so lwk it wasn't that bad cus it was basically js review for me
but the kids who skipped int3 and were taking this class as sophmores lowk struggled with unit circle
I think you have an exponent 1/2 in your derivative where you meant to have a -1/2
The second exponent 1/2 in the numerator
Hello
Now I get it, it's $\sum_{i = 1}^{n} n = n^{2}$
Ujjawal Gupta
I mean yea
Thats is just adding n to itself n times
*adding
no you need to use pythagorean theorem
Oh yea
There's also method of completing the square
And factoring
why did you re-add the ^(1/2) to the denominator on the second step there
Does anyone recommend any good videos that clearly and effectively explain the unit circle and how to apply it? Im having difficulty understanding it and using it for my school work š
what part of unit circle
the whole thingš
Can you explain more specifically what confuses you? The concept of a circle centered on (0,0) with radius 1 shouldn't take a video to explain.
No like
There are basic stuff (such as the x axis is always cosx, y axis is always sinx)
Or trigonometric transformations? (Such sin(90-x) = cosx}
Yeah, nah not that thatās obviously easy, but like the degrees given in the circle and the fractions with pi and the fractions on the outside
In some educational contexts, however, "unit circle" refers not just to the circle, but to an excessively complex diagram full of coordinates and angles for a dozen+ particular points.
Ah like, 2Ļ/5 = x°?
Im sorry if i canāt really explain well š
No its ok
Yeah
