#precalculus
1 messages ยท Page 213 of 1
asymptotes arent part of the function at all
^^
they're just lines towards which the function approaches, but never intersects it
Thatโs true.
oh
Thatโs also true
for example, (x-1)(x-2)(x-3)/x^7
well one part of the function approaches but never intersects its respective asymptote?
this one crosses its own horizontal asymptote at y=0, thrice
hmm
lmao
eHh
this cannot happen if all you're considering is rational functions
Itโs 1:26 AM. Lemme go grab a soda and then we talk asymptotes
but rational functions are not the only kind of function out there
so....for my question....
since I cannot factor the denominator I need to use quadratic formula
True
and the horizontal asymptote is y=0
In analytic geometry, an asymptote of a curve is a line such that the distance between the curve and the line approaches zero as one or both of the x or y coordinates tends to infinity.
nice
sUL.Ly
what "k" means ? for an example, X=K(pi) or (pi) : 2 + 2 (pi) k.
we are using this with sin and cos stuff
in that case, k most likely denotes an integer
is it important to have it or can i just skip it ?
very important
i still cant find it usefull
find all real x that satisfy sin(x)=0
for an example ?
yes
so it can be: x0 = 0 + ๐ โ ๐ or x0 = ๐ + 2๐ โ ๐
x=pi*k is enough, and remember to state that k is an integer
also im really confused about this: the highest point 1 took: x= ๐/2 + 2k๐.
i mean how, if 2๐ is on 0
SIN line
and its like 3/4 of periode diffrence
wait
if k is there mean that im using difference between max and min points without starting point 0k
@noble thistle the extrema (maxes and mins) of the sin function are the zeroes of the cos function
Think about where cos is zero
Weird, How could x-coordinate be positive for a point on Quadrant II?
This is what I picture
yeh, the question doesn't make sense
tahts what is thinking
That means that the editor of that textbook wasn't caring at all.
Sin(a) + cos(3a) = ??
I am supposed to make it into a product and simplify. The theme is sum and difference into product.
Hi!
can anyone help me find the name of this book
it's for my ap stats 12 course
seems like pearson something but can't find it
@harsh cipher
https://www.chino.k12.ca.us/Page/14454
Lol yes I've done some googling
It wants me to solve this system of equations
Iโm not sure where to start
Do I use something like substitution
<@&286206848099549185> does ayone know this wtf
tan(x) = -v/u
cosx(u-vtanx)=secx
cosx(u+v^2/u)=secx
(u+v^2/u)=sec^2x
u+v^2/u=1+tan^x
u+v^2/u=1+v^2/u^2
u(1+v^2/u^2)=1+v^2/u^2
u=1
v=-tan(x)
if you plug this in into the first equation, everything checks out
sin(x)-tan(x)cos(x)=0
for the second equation
cos(x)-tan(x)sin(x)=secx
cos^2(x)-sin^2(x)=0
cos(2x)=0
2x=pi/2+pi*n
x=pi/4+pi/2*n
u=1 and v=tan(pi/4+pi/2*n)
if you look at the unit circle, tan(pi/4+pi/2*n) is equal to either 1 or -1 depending on n
hey guys
can anyone try youtube.com
their bgc is white?
wtf?
nm
ip reset and flush dns
hi
if a pie chart does not display any numbers.
What word would I use to describe that the information is inaccurate?
what are you referring to when you say "information"
a par chart without numbers doesn't mean that chart itself is inaccurate
you can try estimating the percentage of each part and comparing to any other information
are you able to provide us with a visual?
sure
^
I think an image might help us understand it better
the question is asking if the diagram is well-suited for displaying the data
like some diagrams won't work with certain data
I think you can say that
awesome
depends on what you actually want
the chart it self would have to label "first 120..."
a way I could see a person answering "yes" is that you can still compare the sizes of each part and determine which is most/least common
and it does display relative amounts
which genres are more common etc
if you had extremely good measurement tools, you could obtain the numbers
but ofc it would be better if they were given on the diagram
this isn't a difference of squares
$(2x)^3 - (3y)^3 = (2x - 3y)[(2x)^2 + (2x)(3y) + (3y)^2]$
Ann:
yes but why did symbolab write it differently?
I can see from the refined answer that its (x)(y)
which is 6xy
i don't know! symbolab is crap!
okay
mhm?
shh they're still typing
$f(z) = z^3 + pz^2 + qz - 15 , f(z) = 0 has three roots which are a , 5/a , (a + 5/a -1 )$
tex gore
$f(z) = z^3 + pz^2 + qz - 15 , f(z) = 0$ has three roots which are $a , 5/a , (a + \frac5a -1 )$
are you sure you didn't mean $\frac{a+5}{a-1}$
Ann:
for that last root
no
Publius:
this?
yes
ok so what are you asked for
to solve for p
p only?
as i see it, system of equations
ok so what is your difficulty
not sure where to start
vieta's formulas
i knew you're gonna hit me with a better method... time to google lol
denoting the roots as $r_1, r_2, r_3$, you have $\begin{cases} -p = r_1 + r_2 + r_3 \ q = r_1r_2 + r_2r_3 + r_3r_1 \ -(-15) = r_1r_2r_3 \end{cases}$
Ann:
1 radian is roughly 57.2958 degrees
compare 2 to 0, pi/2, pi, 3pi/2 and 2pi
what exactly is a fundamental vector?
I need help converting this problem into standard form
the standard form looks like a(x-h)^2 + k
yis
just looked it up, heres what i found
but lets get onto the helping
so you have to find h and k here
$h=\frac{-b}{2a}$
Jaboi:
and $k=f(h)$
Jaboi:
so, I'm plugging in 1 to get k, is that right?
got it

k = 5?
yes
what's next?
ok. Thank you for helping me!
np!
How would you find the axis of symmetry for the function?
@carmine elbow if its quadratic in x
Then axis of symetry is given by x=-b/2a..where a and b denotes the things they generally denote in a quadratic
@slender bay parantheses
Sure
No, -9(x-1)^2 +5 @unique jewel
What steps do you usually follow to draw a function's graph ?
Great, now we're trying to find a remarquable point !
-b/2a = -8/4 = -2
Now your turn, replace x by -2 and find the value of y
-2/1 right
Oh yeah oops ๐คฃ sorry sorry !
Iโm confused, are you helping me, him, or both of us?
both of us
Ok
-9 (x-1)ยฒ +5 , k = 5 and h =1
@unique jewel @carmine elbow
Ok
Where did the -8 come from when you were explaining it earlier?
,rotate
Got it
like in the picture right where that like chart is ?]
@narrow peak
May someone solve the question, and i feel i would follow better
don't need to draw the chart thou
@carmine elbow what -8 exactly
Oh ! I replaced (-b) by its value (-8)
Alright I'll do
is this the answer ?
@narrow peak @unique jewel
is the next question
lol and thats it
is ur y intercept @ 5
I found different results, lemme check your answer
,w graph 2xยฒ+8x+5
epic
,w factor 2xยฒ+8x+5
just plug in x values of 1,2,3,4,5
get the y value for each
plot those points
and draw the curve
,rotate
You solved the equation 2xยฒ+8x+3 in order to find the two points where the curve meets the x axis
Nvm, the negative 8 was for the other personโs problem @unique jewel
@atomic talon
You let X be xยฒ and then u get an easy equation that you can solve
But don't forget that you've found the values for X not for small x
If X = a then xยฒ = a x = โa or x = -โa etc ...
Anytime
question
Determine the full expanded equation of a polynomial if it has a root at x=2 with multiplicity 1, a root at x= -3 with multiplicity 2, and a y -intercept (-36).
@harsh cipher write it out
You have the factors
And the y int
And an unknown leading coefficient
No you cant have that minus 36 there
oh
Because that changes the polynomial
then I must substitute y = -36?
I see
one minute please
okay then
(2)(x-2)((x+3)^2)
(2x^3)+(8x^2)-(6x)-(36)
๐
@fleet yew ty!
I am brain dead ?
what r some good pre calc textbooks
i've came across another problem
((3x-2)^-2)/((2x^2)^2))
wow Ann is not around today
what's your question? @harsh cipher
simplify and answer with positive exponents only
$\frac{{(3x-2)}^{-2}}{{(2x^{2})}^2}$
Silver Hunter:
well, what can you do to get the top term to have a positive exponent?
yes we write 1/(x)
then what can you do to $(3x-2)^{-2}$
integral exponent rule
Silver Hunter:
yes
? how did you get that?
it's wrong
$x^{-n}=\frac{1}{x^n}$
Silver Hunter:
yes I understand that
Silver Hunter:
how can we change that to a positive exponent
okay but the orginal question is (3x)^-2
we can say $(3x-2)^{-2}=\frac{1}{(3x-2)^2}$
Silver Hunter:
((3x-2)^-2)/((2x^2)^2))
was this not your expression?
wrote it wrong
oh ok
okay
if a=(3x)
so then its 1/(3x)^2?
yup
in all seriousness, isn't this algebra and not precalc
the first lesson goes over the exponent laws that everyone somehow forgot
everyone taking the class, that is
you don't necessarily need to have a fraction in the numerator. if you have a negative exponent in the numerator, you know then that you have to move it from a numerator to a denominator
but we don't a negative exponent in the denom
you know then that you have to move it from a numerator to a denominator
meh
this whole "have to" mindset
you never """have to""" do anything
I'm trying to make it simpler
ยฏ_(ใ)_/ยฏ
they don't necessarily need to, but they need to have positive exponents so they need to in this case
there's a difference between a requirement you see right there on the paper and a nebulous "have to" that makes the student think negative exponents are actually illegal or something
let me show you the picture of the equation
also, y'all have been misusing the word "equation"
there's a difference between an equation and an expression: the former consists of two of the latter joined by an equals sign
okay!
well, moving on
awesome
if you want to have positive exponents, you want to move any negative exponents in the numerator to the denominator, right?
because essentially $\frac{x^{-n}}{1}=\frac{1}{x^n}$
Silver Hunter:
that's much better now as far as explanations go
bc this time instead of imposing arbitrary rules, you motivate
so if you moved $(3x)^{-2}$ to the denominator
Silver Hunter:
it would be same as $\frac{1}{(3x)^{2}(2x^2)^2}$
Silver Hunter:
uh yes
are you confused?
I can give you another way to look at it
ok
so you don't always need to think the numerator and denominator as separate expressions
I agree
so for simplifying
and multiply the coefficients
yes
and you should be done
๐
Does anyone know how to do this?
do you know the relationship between a polynomial's degree and the number of roots it can have
ok first off
i'm not your bro. please don't call me that
second, we don't give out answers here.
@viscid thistle @atomic talon
help me understand then
i think its asking how many numbers could fit in x right?
or does it mean what actual value fits in the x
bc if its asking how many solutions it would be 1 right? bc only 2 would work there
look up ''the fundamental theorem of algebra''
My bad then
i think its asking how many numbers could fit in x right?
this is a bad way of putting it
a polynomial equation can have at most as many distinct roots as its degree
you know what the degree of a polynomial is, right
so can you tell me the degree of the polynomial x^6 - 64
no
then what
the degree of x^6 - 64 is 6, not 2.
you told me you knew what the degree of a polynomial was, but either you were confused about it or you lied.
some people have actually lied to me about this sort of stuff. dunno why they do it.
anyway
that's beside the point
forgetting about this problem for a moment
what do you think the DEGREE of a polynomial is
exponet
exponent?
LOL MIA
why what
why are u questioning me
The degree of a polynomial is the highest power in the polynomial
like im confused
i'm trying to get you to phrase things clearly, which is the first step to actually understanding things.
the degree of a polynomial is the highest exponent of x appearing in the polynomial (with a nonzero coefficient)
is that right tho
is that why 6 was the degree
bc it was the exponet
the only exponet
but if there were more it would be the highest
like u said
6 is the exponent on x^6 and there are no higher exponents on any x's around
Dont just tell them
use double angle
thx @slender bay
@serene heath so sin 4a is sin (2*2a)?
yes
Uhm thanks. I'll try it
@mia#0666 the answer its 2 so D, if you are still looking for it. Basically because:
2^6 - 64 = 0
64 - 64 = 0
0 = 0
Proven
how do i find the fundamental frequency of the superposition of two sinusoids
and btw they arent harmonics
@viscid thistle
Who would use discord during an exam..?
fr
Hi guys, I need to find cos B and tan B
I found cos B
But I'm unsure about tan B
Can you tell me your answer for cos B?
Sorry the working is a bit messy
@leaden stratus
Ping me when u reply:)
@viscid thistle option 3 as at x=2 deno becomes 0
@viscid thistle (next time try looking for values that X cannot equal, or look for the vertical asymptotes of the graph.)
Since $\sin{\alpha}=\frac{1}{2}$, $\alpha=30$. Since $\alpha+\beta=90, \beta=60 \implies \cos{\beta}=\cos{60}=\frac{1}{2}$ and $\tan{60}=\frac{\sqrt{3}}{3}$
ฮนฯฮนฯฮท_ัฮฑะบฮฑgฮน:
@soft mica 1/2
yep that's correct
when you were working out cos beta what did you use for the value of beta?
@leaden stratus
@soft mica 360 - 2alpha
Because we studied the double angles
Actually tan B result is sqrt3 according to my book
yep so beta is 60 degrees
We could find cos B by doing cos (alpha - beta)
and tan 60 is an exact value that is equal to sqrt3
Yup, but you should find it only using trig formulas
you mean cos ((a+b)-a)?
Ueah what is the prob
U see the modulus..break it
U will find two linear functions at the breaking point whose graph is a straight line...and then u can either plot to solve or u can solve them algebraically as well
The breaking point is x=-1/2
Break it into seperate functions like if x-a>0 then replace modulous with a bracket only and if x-a<0 replace it with a bracket with a negative sign outside
Hey guys, this is probably a rlly easy question, I know I just have to use substitution but I dont know what to do next ;-;
so expand it?
Yeah
well Ill try it again
haha ok but I need to solve it using the equations
Ban
tbh, there is no answer there lol
Sadlyf but ban
unless u go do pixel measurements
Bruh (1,-3)
no there should be to on the two places it crosses over
I can clearly see it
two answers
Me also
well i can't :/
@desert crystal dont u see the pic
and neither has the person
Ban plep you crossed the line dude it's end of the line now
nooo
๐
I shouldnt use the pic to solve it
no lol
Anyways bro solve that shit simultaneously whoever asked it and apply the quadratic formula if you can't factorise
u cant draw it irl
Ueaj...good to go thwn
Yea now subs it in the linear obtain y and check calculations
show workign
@desert crystal maybe u screwd
@slender bay are you a nihilist
If you're girl you'll have a nice handwriting
Unlike me
so u have:
(x - 4)^2 + (y-2)^2 = 25
and y = x -3
so you replace y, with x - 3
(x - 4)^2 + (x - 3 - 2)^2 = 25
which is:
(x - 4)^2 + (x - 5)^2 = 25
then you can expand both using the rule
(a - b)^2 = a^2 - 2ab + b^2
@lost sphinx how did u know
Well fricl
Your pfp dude
It should be:
2x^2 - 8x + 16 + 2x^2 - 10x + 25 = 25
Wjere did ur 16 go
I can spot a nihilist in the darkness of the night
lol oh
nihilists don't exist
We do
hang on ill do it again
because its unnihilistic to be a nihilist
ugh im so dumb
Hey i am present here.
Plep I know your dirty secret now
@desert crystal yeah..everybody is
lol
Except TAO
I am not dumb you're offending me now pmg
im asking this chat cuz im too scared to ask my nerdy friends
I don't know but in India there's this saying "jisne kari sharam uske phootey karam" so like
Everyrhing here is relative
Which means if u ger shy ..u are to suffer
It means if you're shy you probably are pretending to be something you are not
gg
Or you have that hidden regret
im not pretending im not dumb, Im just in the top maths class and dont want to drag people down
like bother them
Who cares if u do
I care
Bruv I was not saying you're dumb
wtf is going on
@desert crystal u did the question good job, ur not dumb
As i said..its relative
awww thats so sweet but I do rlly need to improve my maths
Why are u into maths
Ping @slender bay any time he's two times jee topper
bruh im not into maths
anyway guys i have a precalc question for ya'll
why the hell does x^2 + y^2 = r^2 draw a circle
it just does
It doesn't have the xy term
hint: its pythagoras
Dude...dosnt matter
yea?
Hold up
The amswer ks coming
I am getting a feel by the pythagoras thingy
Distsnce formual is indeed pythagoras
And why should we evn be bothering bt that๐
Im pretty sure complex numbers aren't involved with this
they already completed it
Complex numbers can be used to derive this @harsh condor
|z-z0|=r
z0=0
Take modulous
We know that this equation is supposed to represent a complex number that rotates about a fixed point
I was off to some work
We know that this equation is supposed to represent a complex number that rotates about a fixed point
bad desc
what does that even mean
Thats how you make a mess out of nowhere๐
Yeaj
@carmine elbow what exactly are you having trouble with
The exact problem is she/ he posts the problem and within 10 minutes she disappears again reappear after 1 hr, post it again and again show the same periodic behavior..thats all
Are you trying to find the maximum? Or are you trying to solve for that inequality?
Two different problems
Are u still here with us
Ok...do u know how to break modulus
?
I mesn do u know thr definition of modulus function
til these functions deserves a name
I am out..of it
someone asked me this q and can someone tell me what this question means
the question is :- out of the statements x^2+y^2=r^2 and y=โ(r^2-x^2) which options states that y is a function of x
What kind of map?
Each element of the domain (x) is associated with ONLY one value of the codomain (y)
For every x there can be only one y
Make sense?
you mean there can be exactly one value of f(x)?
Yes
For each value of x
If you want to think of it graphically
There is something called the "vertical line test"
A vertical line (any vertical line) may only pass through the function ONCE
but what does his question mean
It means that which one says
That y depends on x and follows the vertical line test.
When we say that y is a function of f
y = f(x)
It means that y is solely dependent on the value of x
So y = (some collection of terms of x)
What is a modulus function?
Square roots don't have negative inputs. x^2 does accept negative input.
@carmine elbow modulus of a number z is its distance from zero
So the modulus of 5 is 5
The modulus of -5 is 5
It's the absolute value
@heady jewel which equation says y = something else
ok. I think I get it
I ask because I don't know how to find the minimum/maximum value for an absolute value function. My professor is saying that it's possible even though Mathway is saying that only quadratic functions can have max/min
Absolute value functions do have a max and a min
Do you have a specific problem i can use as an example to show you?
Ping me if you still need help
@viscid thistle find the integral
Isn't that the problem?
I didn't use a calculator
And uh you just take the power of -4 outside the log and solve -4*(log4[256])
256 is 4 raised to the power 4
There you have it
Hello
@fleet yew -8|2x+1|+6
AMD:
where the coordinates of the vertex (the max or min) are (h, k)
so in this example, you will need to factor out what's inside the absolute value sign
$-8|2x+1|+6 = -8|2(x+\frac{1}{2})| + 6$
AMD:
So this problem log8 x + log8(x + 3) = log8(x + 15)
What do I do
I got x^2 * 3x = x + 15
$\log_{8}(x) + \log_{8}(x+3) = \log_{8}(x+15)$
AMD:
$x^2 + 3x = x + 15$
AMD:
$x^2 + 2x - 15 = 0$
AMD:
o
Solve the logarithmic equation algebraically. Approximate the result to three decimal places.Solve the logarithmic equation algebraically. Approximate the result to three decimal places.
Why decimal though
Wouldn't the answer just be 5 and -3?
@sharp marsh you factored wrong
(x + 5) (x-3) = 0
x = -5, 3
got your signs switched up
oops mb
watch out for extraneous solutions
A terrible identity to verify!
Where can I start?
Would it be okay to start from tan and write it as sin/cos?
Yes since everything on RHS is all sin and cos
What more, now? @lilac pier
you get sin^2 (a/2)
you should know sin^2 (x) + cos^2 (x) = 1, so sin^2 (a/2) + cos^2 (a/2) = 1. This way you get sin^2 (a/2) = 1 - cos^2 (a/2)
get what?
you get sin^2 (a/2)
@lilac pier
You have tan(a/2)
That's = sin(a/2) / cos(a/2)
Oh
Actually yeah I realize my mistake lol sorry
You have to use the double angle identity of sin. sin(A) = 2Sin(A/2)Cos(A/2)
Tan(A/2) = Sin(A/2) / Cos(A/2)
yeah mb
cos(a/2) in the denomintor from tan
cancels out the cos(a/2) which came in the double angle identity of sin
2sin(a/2)cos(a/2) * sin(a/2)/cos(a/2) cos (a/2) cancels out
Oh it was your mistake
Yeah.
Yeah now use sin^2 ( a/2 ) = 1 - cos^2 (a/2)
So 2(1-cos^2(a/2))
Sub e^x= t
Reduces to a quadratic in "t"
Then use quadratic formula..or u can factorise..
@sharp marsh
@lilac pier
Its still not solved or wht
@leaden stratus I'm really sorry I was gone
Now he's gone...an eye for an eye
Now u are up : he s gone..an eye for an eye
Iโm struggling on this problem
Because I used rational root theorem on this polynomial
But when I graph the polynomial on my calculator it says the answer is in between 4 and 5 but using rational root theorem none of my possible zeroes are in between 4 and 5
So the answer is irrational but if I plug in 4.372 it says it is wrong
no
you are not asked to actually solve the equation
you are only asked to analyze it using the rational root theorem
you wrote down the POSSIBLE rational roots as ยฑ(1,2,3,4,6,8,12,24)/(1,2,3,6)
among the rational numbers whose numerator is one of 1, 2, 3, 4, 6, 8, 12, 24 and whose denominator is one of 1, 2, 3, 6
which one is the largest?
@odd helm
#Being ignored๐
3 minutes isn't quite as big of a delay to be associated with ghosting
#Time is passing
@leaden stratus It's better to take RHS first
What can we do?
you can make cos(A) = 2Cos^2 (A/2) - 1
Sure?
Uhm, do I have to rewrite sin^2(a/2)?
no
It is -2cos(a) so -2(2cos^2(a/2)-1)???
2sin^2(a/4)
?
Yeah
did u use an identity again
Sorry I wasnโt ignoring Ann I just went offline so the answer would be 24 I guess
Thank u
Hi
question
question b
second part of the equation
why is the answer log base 2 8y in the numerator
sorry about the parentheses
i get that the denom is root(x)
I don't understand
$3 = \log_2(8)$
ramonov:
take your time
hahahaha
so am I supposed to recognize that
the 3 can be written as log base 2 8?
basic application of a log law
in order to express the original equation as single logarithm
I do need to express the 3 as log base 2?
for this question, yes
you need them to be the same base
thank you
I will write it like that from now on.
@willow bear merci
@steel venture i got it
ok ๐
Do combinatorics belong here?
yeah i guess
This is how I started
but Idk how to continue
we never did the !
I know what it means but no special operations or rules on what to do with it
and our teacher only gave us the basic formulas
now, I know this is comparing 2 combinations
but I got stuck here and have no idea what to do
ah ok
