#help-28
1 messages · Page 313 of 1
Note, polynomials with real coefficients obey Complex Conjugate Root Theorem
yeah, thats something like when i-1 is a root, so is i+1, right?
yep
so since i is a root, you require -i to be a root
so you need a poly with x=1,2,i,-i as roots
okay so the factoring would be (x-1)(x-2)(x(-i))?
no
cause you know you have 4 roots
and (x(-i)) is nonsense for being a factor
if x=1 is a root, then x-1 is a factor is correct
apply that for the rest.
$x \pm i$
Vladilena Milizé
ayy it worked
well it also works for the question
okay so would the factors be -1,-2, -i(isn't -i = 1?), and i? I thought that factors were the opposite of roots?
.....
$i = \sqrt{-1}$
Vladilena Milizé
so 1) You seemed to ignore what I said, about x=1 means x-1 is a factor
2) No
your math teachers lied to you for past few years that it right 😄
okay, i'm genuinely confused. could you maybe walk through this one with me, and maybe I can try the next one on my own? the factoring part is really confusing me
what is the factor associated with x=2?
what mosh said is what you need to do
"You seemed to ignore what I said, about x=1 means x-1 is a factor"
apply what you did for x=1 to the other 3 roots
then expand
I don't need an echo btw
(x-2) right
(x-i)
and the last root?
(x+i)
Mosh
okay, i see. so then, do i distribute?
do last 2 first
you expand that to write it in standard form
makes everything easier
so i would do x * x, x*-2, -1*x, -1 * -2 then repeat for the x and i on the other side or distribute through the whole thing?
huh
you expand the entire thing.
first one
after you do it for both do the same thing for the 2 new polynomials you just made
kaii
you have the right variables you need to multiple the 2 instead of add
$(x^2-2x-x+2)(x^2+ix-ix+i^2)$
Vladilena Milizé
then simplify and expand again
Uh how much about imaginary numbers do you already know?
i dont think im doing something right..? x^2 * x^2 gives x^4,, x^2 * ix gives ix^2 and reverse for -ix and after that im stuck
i took alg II during 10 grade, or i was, but covid hit and the class stopped midway
and i never got to finish it
I see
the school system tried doing class over video call, but they just called it quits so my knowledge really isnt all that good. so now im struggling in precalc / math analysis
Uh I don't think just doing one problem will help you learn anything
Imaginary numbers is not something
U can learn on plain text
Are you familar with imaginary plane?
How multiplying by i rotates by 90 degress?
yeah we did some imaginary numbers, i remember that vaguely
Ok ig u dont know about this that when u a point a+bi multiply c+di a+bi rotates by the angle of c+di and streches by its magnetude
From where u were stuck u were stuck
U were using plain algebra to compute that
But it has a geometric meaning
without that it's not complete
Are you familar with this?
I don't think so
i barely learned about it before the cut off, so not really. everything you're saying seems kinda new to me
Yes u have to expand them but if u just understand the arethmetic it will never be clear
U can look into 3b1bs lockdown math series
There is a 1hr video about imaginary numbers
ok, imma do that asap. thanks for that
yeah ive seen that before, thats why i said i=1; although i was incorrect its i^2=-1
https://youtu.be/5PcpBw5Hbwo is this the video @torn jolt
Intro to the geometry complex numbers.
Full playlist: https://www.youtube.com/playlist?list=PLZHQObOWTQDP5CVelJJ1bNDouqrAhVPev
Home page: https://www.3blue1brown.com
Brought to you by you: https://3b1b.co/ldm-thanks
Beautiful pictorial summary by @ThuyNganVu:
https://twitter.com/ThuyNganVu/status/1258219199769440257
Errors:
- On the first sket...
$i = \sqrt{-1}$
Vladilena Milizé
simplify each polynomial first
and turn the $i^2$ into a number
Vladilena Milizé
then expand
Wait
If u don't understand
(a+bi) (c+di)
And just solve it
Using algebra
Then it's not enough
Understand what it does completely
Which he dosent first af all
i think i might just watch a few lectures, and come back because I'm missing a huge chunk. as if something isn't clicking for me at all. im trying to apply it, and it's not working + I don't want to waste your time when someone else could use it better. thank you though, seriously for pointing me in the right direction.
You are missing a huge chunk
Multiplying by imaginary numbers isn't that just expanding and giving out the answer to get marks ☠️ it has to do with geometry
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how do i solve this
you chose the correct sub, but you didn't use that sub?
wdym
@kindred cliff Has your question been resolved?
i did
@kindred cliff Has your question been resolved?
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how to simplify this expression?
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If it asks find a general solution to y' = e^x, is this first order differential equation?
or does there to be y on the right hand side like solve y' = 1-y^2?
As long as the highest-order derivative is a first derivative, it is a first order differential equation
In the same way that x→ax+b is a linear function as long as a≠0, even if b=0
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i don't get it
there can't be a global maximum
the function is unbounded
holy fucking shit
that's such a bad way to write that
0<=x,y<=1
is apparently supposed to mean two different compound inequalities tf
this apparently means
0<=x<=1
AND
0<=y<=1
i thought that this meant 0<=x, y<=1
bullshit
@vapid barn Has your question been resolved?
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How do you test that 2 lines are perpendicular in 3d ?
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@timid girder Has your question been resolved?
that third photo looks right
Really?
Wow
I’m surprised if that’s the answer because it’s super out of my league in terms of difficulty
This problem is extra credit in my alg 2 class
apparently it wasn't 🤷 good job
What is your level in math
I just wanna be more confident I can take your word for it
You shouldn't take my word for it. That math should stand for itself. How did you get that solution?
I kind of just composed a bunch of probability equations
Good
There's three cases one rolls and she stops, rolls a single 4 and rolls again, rolls no 4's and rolls again.
You have those three
the rolls and stops needs a 4,4 which is only 1/36 chances
The rolls one 4 and rolls again means she either got x,4 or 4,x. So there's a 10/36 probability, and a 1/6 for a 4 on the third roll
multiply those, that's your second term.
And so on for the third case
Can you do the third case
you tell me. It's the same reasoning as the second
The third case that she rolls one x and one x. There is a 25/36 probability and a 1/36 on the 3rd roll
So 25/1296
yep, because there's only 5 choices for each x (since neither can be 4)
Yeah
But what’s the next step?
First case: 1/36
Second case: 10/216
Third case: 25/1296
When you have mutually exclusive events (like you created here) to find the probability of any of those events happening, you just add the probabilities together
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Hi I am having hard time setting up eq for this poisson distribution
The question is that there is a goose attack happening at the rate of 5 attacks per week. A week is goose-free if no attack occurs that week.
and i want to determine the probability of goose free week
If X is the number of goose free weeks given an interval, then $X \sim Poisson(5)$ so $\frac{e^{-5} \cdot (\frac{5}{1})^1}{1!}$, is this correct?
meguuuuu
@wheat talon Has your question been resolved?
<@&286206848099549185>
@wheat talon Has your question been resolved?
<@&286206848099549185>
<@&286206848099549185>
@wheat talon Has your question been resolved?
anyone?
Oh
Wait so when I have a question like this
What is a probability that in an interval of 16 weeks, there is at least 2 goose free day
What is X going to be?
because right now i have X defined as number of goose free weeks given an interval
Oh wait, is it going to be like this
Suppose that X is the number of goose attacks in an interval
Then P(X=14) is the total number of goose attacks in an interval of 16 weeks and 1 - P(x=14) is the total number of goose free weeks? @gritty rose
What is X here? The same?
X is the number of goose attacks in an interval
You used X here to denote something else
Don't use the same variable for different things
I dont know which one to use thats why sorry
Why does P(X=0) make sense for when X is number of goose free weeks though
doesnt this mean 0 number of goose free attacks
Omg I'm so sorry
This was right all along
What is the exact question here
let me show you the question
Yea that's best
Double nevermind. This was right all along
Is this an exam? Why does it have points?
Use binomial distribution for c
@wheat talon Has your question been resolved?
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Not sure how to begin showing this
<@&286206848099549185>
How do you solve this question?
um idk that's why i posted the question
and why are u pinging helpers for my question 
Lmaooo
haha
@grizzled lance Has your question been resolved?
Thoughts: So starting with showing that if P' lies on the circle, then P lies on the circle. $\frac{a}{b^*} = \frac{ab}{b_x^2+b_y^2}$. where $b=b_x+b_yi$ and likewise for the other complex numbers
azeem321
Do you know how to write a family of circle
Not sure how both $\frac{a}{b^*}$ and $ab$ can lie on the circle unless $b_x^2 + b_y^2 = 1$
azeem321
tangent at a given point on a line?
azeem321
?
y/no (family of circles sharing a common tangent line at a specific given point)
if not, look it up
you can directly conclude
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Can anyone please help me understand why the right side of the equation slope was taken -1
@nocturne creek Has your question been resolved?
We're studying parabolas, and this was a method of identifying how to check if an equation is a parabola or not. I think what we did here has some pre requisties from pair of straight lines but i didnt do that course, what i know is that slope of a line is -A/B so i can see how the left side of the equation slope is 1, but then the teacher said the right side of the equation slope is -1 without explaining, i can see how -(4+2c)/-2c is the slope, but i dont understand where the -1 comes from
@nocturne creek Has your question been resolved?
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Bruh what
The answer is 2
No, I got -2
15
0?
alright close this channel
Lol
Xd
if not, you are trolling, so close this channel and stop
Bruh
ITS ZERO
I happen to be very good at maths, it's zero? I used calculator too.
Anyway, goodluck if you don't trust me. I'll exit.
<@&268886789983436800> ^
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Been really confused on this problem, can someone please help me.
Ummm....
<@&268886789983436800> we have a troll posting this in various channels
ty
It says it's rotated about x=2
By about it means with it?
So its now y = 2
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How do I find the side lengths
@lucid void Has your question been resolved?
<@&286206848099549185>
@lucid void Has your question been resolved?
@lucid void area is proportional to length^2
meaning area = b*length^2
notice that length can be anything
it could be the perimeter of the shape, or the side length, whatever
there is some constant b that makes the equation true
let s be the scale factor, then s*length_1 = length_2
That is the length of the second shape is scaled by a factor of s
what information is given?
$$area_1 = blength_1^2 = 4$$ $$area_2 = blength_2^2 = 25$$
DETOX
this is all the information you need to solve for s
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(echelon method)
2x + 7y = -8
-2x + 3y = -12
See rules on helper pings
Oh
Do you need to follow this method
Or..?
Yeah it say's "Use"
First I believe you would want to check if this system has multiple solutions
If it only has one unique solution then use the echelon method
why is that?
Wouldn't you want the system to have only one unique solution?
Otherwise there would be many solutions
Yes, there would. But remember what the echelon form for a linear system with infinitely many equations would look like.
It has two equations
That could still mean there could be infinitely many solutions, or none.
2 7 | -8
-2 3 | -12
R1 + R2
2 7 | -8
0 10 | -20
So 10y = -20
y = -2
Then sub in the first equation
Ohhh
Yeah
Weird
Also this is a different question
I guess i don't really know I missed like 2 days of school
This is what you wanted right?
Yeah thanks
Did you ever learn how to represent this as a matrix?
I don't even know what a matrix is
#whentheteachersaysechelonmethodbutthestudentsprobablyhavenocluewhyorhow
Basically, what we understand under echelon form is this
That you get a "reverse staircase"
This is what happens when you miss days
Can I ask you a question?
That's what we are here for
Alright so If we're going to college why do we need so much of this useless math
The only day you're absent and something cool happens in the school 😢
Because it's useful
I wouldn't say this is useless
Literally pointless math that im never going to ever need nor remember
Linear systems are used everywhere
This is some of the basics
at least as far as STEM goes
I'm just saying in general
Do you like computer programming?
You'll have to cope
Yeah
Until you have an option to not choose maths
That's what i do
Then Linear algebra will be useful to you
How'd you know that-
Some parts of maths are used a lot in maths
Graphics
^
I meant computer science lol
Nah that I program-
But thank you guys - 🥲
If you need anything dealin with computers hmu tho
Just confirm with your teacher whether this is what he/she wanted with the echelon method
Well, again, if you choose anything related to STEM, you'll need mathematics.
CS has a lot of interesting discrete mathematics going on e.g.
Thanks Again
@torn jolt Has your question been resolved?
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why urgent
because i dont have time
??
private stuff
is this an ongoing test or what
they have their own lives too
what tools can you use for this problem?
can you use code?
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hello, i'm not sure where to start with this question. we haven't learnt integration yet and i'm not very well versed with the characteristics of inverse trig functions. i'm aware that c is the y-intercept and that the derivative of arcsin is 1/(1-x^2).
If f(x) = Aarcsin(Bx) + C, what's f'(x)?
^^
AB/ \sqrt 1-(Bx)^2 ?
"derivative of arcsin is 1/(1-x^2)" you forgot the sqrt, though it was probably a typo, but still
oh yea mb
Yeah, you need the √. Also, you forgot a parenthesis and the chain rule
Don't forget chain rule
there's product rule too right
There's no product
oh a's a constant forgot
You're not done tho. It's not Bx²
AB/ \sqrt 1-(Bx)^2 ?
was i forgetting the parenthesis?
yea i don't really get how the 16 and 9 are in the square root
You need the integrand to be of the form 1 - cx² in order to set things equal to each other. Perhaps you could factor something from 16 - 9x²? You won't be left with a whole number as a coefficient, but oh well
sorry i don't really understand what you're saying
do you mean like 9(16/9-x^2)?
but i dont see how that would help
16(1-9/16x^2) yeh?
You can simplify the while expression. Remember that's on the denominator
ahh i dont really feel like im simplifying it but
i got
AB \sqrt(1-9/16 x^2) / 4(1-9/16 x^2)
•_•
yea..
I just want you to simplify -4/[4sqrt(1 - (9/16)x²)]
I don't know know why you have AB here
ohh
that's just
-1/sqrt(1-(9/16)x^2)
so b is just 9/16?
but idk why the entire expression is negative
Arcsin is odd, so we can absorb the sign into A anyways
So we can just stick to +3/4
Yep
ohh
then i can just solve
alright
thank you for accepting my stupidness
you've beena great help
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how do you prove that the monotone class generated by a ring is actually a ring?
In measure theory and probability, the monotone class theorem connects monotone classes and sigma-algebras. The theorem says that the smallest monotone class containing an algebra of sets
G
{\displaystyle G}
is precisely the smallest 𝜎-algebra containing
G
.
...
@lost copper Has your question been resolved?
I see it's a corollary
But I don't understand how to pass from the case when G is an algebra to that when G is a ring
I know and algebra is a ring containing omega
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hello i need some help on some multiple topics i need to review on but cant remember how todo

mainly Simplifying expressions, factoring and systems of equations
okay so
how would i solve 20-(32x-3)-(4x-10) i know i need to get rid of the parenthesis then solve for simpify x down as low as i can i just got no clue where to start
You can't solve that. You can simplify it
To simplify:
-
Distribute all negatives (and in the process remove parentheses as appropriate)
-
Combine like terms
so take the one and distribute it to the 4x and -10 so that would become 4x+10?
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How would I solve D=2S ∞ - 781.4?
what is 2S inf suppose to be?
I’m not sure it’s the formula my teacher gave me
so the infinite series
Yes
you compute S, then.. evaluate
This is my first time doing this unit, how would I do that
S_n is a geometric series
use the formula for S
$\sum_{n=0}^\infty ar^n=\frac{a}{1-r}, |r|<1$
Mosh
Now would I evaluate a/1-r?
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How should I graph f^-1(x)=2x-4
Graphing 2x - 4: You have your y-intercept and your slope
Are you able to create a graph from this information?
I know how to graph 2x-4, I am just confused on how to graph it when it says f^-1(x)=2x-4
f^-1(x) is especially confusing to me
are you trying to graph the inverse of y=2x-4 or is y=2x-4 your inverse
uh well the origibal equation was f(x)=1/2 x-5
then I inversed it to 2x-4
am I suppose to just graph it like y=2x-4?
that's not what the inverse of that function is
oh
(and to answer this, yes, you'd just graph what you get as the inverse)
however that specific inverse is not correct, so don't graph that
I checked my working but I couldn't find a mistake
can i see?
seems you wrote -5 as 2 lol
wait +
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is this telling me to find the sin A?
i dont understand the fraction of sin A/2
i know that b = 16 after doing the math
oh wait thats the formula for half angle identity
so do you have any questions or did you solve it?
about?
the whole problem
why?
on finding the sin A/2
first did you label all the sides and then find b (noting its a right triangle)
I understand the sin2A part
b = 16
wait let me try something
Have u solved $sin(\frac {A}{2})$
idk7
$\cos(2x) = 1 - 2\sin^2(x)$ then replace 2x with u, and you get: $\cos(u) = 1 - 2\sin^2\qty(\frac{u}{2})$
and then you can plug in ur values and solve for sin(u/2)
Brontochad (Shuri for honorable)
I think they have asked $sin$ not cosine
idk7
i know thats why i said solve for sin
I see
Uh wait
then yes
Ya
2 * (12/20) * (16/20)
$sin(2x) = 2 cos(x) sin(x)$
idk7
which is 416/400 or 26/25?
,w 2 * (12/20) * (16/20)
24/25
because we know that -1 <= sin(x) <= 1, so the value should ALWAYS be in between those values
thats how you can check if your answer is right or wrong
got it
so for the formula of half angle identity
sinA/2
i got plus minus sqrt(4/40)
how would i know if its a positive or a negative?
@slow canopy
alright well the angle is clearly less than 90 degrees so sin(2 * that angle) should also be greater than 0
so it should be positive....but if you are just in geometry you can assume all the trig angles would be positive (up until where you learn about the unit circle)
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I missed around a week of precalculus and i am stuck on specific solutions with multiple trig functions, ex:
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For a codegolf challenge, I need to devise an algorithm f, that takes the first n digits of a real number a, such that for large enough n f(a[:n])=1 if a is rational. And also for the inverse, if a is irrational then there is an infinite increasing sequence of k1, k2, ... such that f(a[:k])=0
My idea for such f is finding whether there is a suffix of that sequence that consists of 2 identical words, like 2929, 312312.
This obviously works for a rational number, because after the second repetition, the added digit must be the same as the first digit on the repetition, so we can shift the repetition.
But I don't know how to prove that this f also works for irrational number, in sense that there is an infinite increasing sequence k1, k2, k3, such that f(a[:k]) =0
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Hi! I need help on this question. Does part a look right?
If so, can I get help on the other parts. Thanks!
Wrong
12 not 24
For example Z/12Z, the cyclic group of order 12
c Z/2Z times Z/2Z times Z/3Z
Where times I mean direct product
Oh okay, that makes sense ill look at that thanks
How could I find a group with that size though?
Abelian cases is standard
Abelian groups of order n: first Prime factorization of n
n=Πp_i^e_i
Then for each e_i choose positive integers f_ij ,f_i1<=f_i2<=… such that their sum is e_i
Then you have an abelian group of order n: direct product of Z/p_i^f_ijZ
For example n=12=2^2*3
So Z/4Z times Z/3Z
Or Z/2Z times Z/2Z times Z/3Z
Those are all different abelian groups of order n up to isomorphism
Non-abelian cases have to be considered individually, no short cut
Oh okay I see... would showing those be enough in this case
You just have to show 2 of them
One for b) one for c)
(Those two happen to be your only choice if you want them all be abelian
Like for c) you can use dihedral group D_6 (or D_12 I always confuse the symbol) coming up with Z/2Z times Z/2Z times Z/3Z might be easier
Oh okay thank you!
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Multiply side a by side b
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(2x+7)^2 but yea
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i have a major test tomarrow can someone help me with stuff so i can get a good grade tomarrow
i have some questions
are you uploading them orrr
he died.
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@jade fulcrum what
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,rotate
use the pythagoras theorem
Hint: WY is the diagonal of the rectangle, WZ is the side. The diagonal and side makes two sides of a triangle
ah yes so interior angles equal the sum of
180
and you can apply
pythagorean theorum?
Pretty sure it was 30 60 90
WZY is a a triangle so you can use it
oh oops
I literally said this
so 9 squared plus 10 squared = ans?
true
No
no
i dunno i was thinking 30 60 90 but the ratios dont match up right
WY is the diagonal
Do you know Pythagorean theorem?
Wasn't asking you
wait what
That's wrong
b2
Improperly formatted
Still wrong
dude its a square + b square = c square
Still not talking to you
and you can change the formula
depending on what you looking for
if you looking for hypotenuse
then its that
if you looking for leg
then its c2 - a2 = b2 or c2-b2 = a2
Then you should have properly said this because a2 means a times 2
im to lazy to type a^2
If you wrote a2, your teacher would mark it wrong, wouldn't they?
depends on paper its really easy to write
simply because its not formatted in ASCII
so you can write it in any way you want
^ is literally just one extra keystroke
or just type alt 0178
ye but mathematically inefficient to do that
As I said a2 and a^2 aren't the same
This is what you have to do for your question
ok
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14 and 16
,rccw
would have been better if part of the trapezoid was not cut off
does the pencil-writing have anything to do with either q14 or q16?
nope
oh sorry
there arent any vals
for F and C
"vals"?
values
those points are still part of your diagram...
would you like it if part of your hand was chopped off because it was deemed to have no value
in any case
what are you having trouble with for q14?
oh ok sorry lmao
the question itself
please do not reply-ping me so often.
like do you add 5x and 3x
very sorry my reply ping is not turned off default
do you understand the relationship between the angles?
forgetting their expressions in terms of x and looking only at the diagram, what can you tell me about the angles DCB and ABC
you mean like opposite,alternate
i'm not testing you on terminology here.
oh they are all supplementary angles?
are they equal? do they add up to something? maybe something else?
they have a intersection point?
they are alternate to each other?
??
i don't know what "alternate" means in this context
i think you're overcomplicating it
they add up to 180°.
sure, yes
ah ok got the ans thx
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ello, i need help. is this the right graph for this function?
yes
are the open and closed points okay?
did i plot and use the right points?
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is the interval (6,10) continuous
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@arctic iron What do you think? Yes or no, and why?
im pretty sure it is because the interval doesnt include 6
if it did i.e. [6,10) then it wouldnt be continuous right
aw wait im pretty sure it would still be continous
how about [0,6) is that also continuous
It is continuous on (6, 10)
This is one of those small details from Calc 1 that I don't exactly remember, unfortunately.
What do you think? Any ideas?
I think so as well - I'm not positive tho (it's once of those tiny things where the concept is there but it's a really small detail)
That link may help
Especially if you know limits. If you don't know limits, don't worry too much
I think the idea is the following:
A graph f(x) is continuous everywhere except when there's a discontinuity there.
Therefore I believe this reasoning is correct.
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Quick question: I have been doing variation tables and it takes way too long to create by substituting values to determine concavity and inflection points. Is their an easier way to?
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@smoky sand I believe there is a third derivative test for inflection points
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✅
I thought that was second derivitive
Third derivative is just the rate of change of concavity. That doesn't have a specific meaning I'm pretty sure
what do you think?
looks like too much reading that I dont know
but other than that case, is it fine to use for inflection points?
This accounts for that case
So yeah
I'm pretty sure there are also issues when the f'(a) = f''(a) = 0
good to know. i read about this a while ago but wasn't sure if it could be used. saves so much time instead creating tables and sutff
😱
Consider this as an example
How do I use this, anything to getme away from variation tables
Is a line concave up or concave down
neither?
neither
Yes. A line has no concavity
can someone simplify the proof into a concrete example?
Here's a better idea.
You give me an example of a problem
That you struggled with
We can walk through it
like for this is there a way to not have to do the table
Are you allowed to use a graphing calculator
Alright then
The issue is finding the concavity immediately surrounding the inflection point
And the simplest way to do that is to plug in a number slightly smaller and slightly larger than the inflection point into the 2nd derivative
wait thats the simplest I thought that was the hard way 😭
so we cant use the proof to do it immediatly?
But you don't know in which direction it changes from
An inflection point can either be concave up to concave down or concave down to concave up
that is why you need to do it for y' and y''
The inflection point itself does not give you that information unfortunately
if this was the simple way what is the hard way...just curious
This is the way. You have to know the sign of the second derivative surrounding the point
My advice to you would be to just get quicker at doing so
I know for concavity it is down if y'' is - but is the same true for y'?
If y' is negative then y is decreasing
A little tip: e^(anything) is always a positive number
You just have to take the sign of each factor in the product
yes so does it have to be within the interval or just -. Cause I can just use the signs rule to determine that without havng to calculate the value to test wheather it is in the interval or not
For smooth functions (which is what you'll usually be working with), the concavity or direction can only change at the zeros. So you only need to choose one point between each zero and then points outside those zeros
for more complex functions that involve e and ln idk what to plug in that would be less than those values
Just choose integers that are between the zeros
Like for this example, I would use -1, 0, 1
-1/2, 1/2
Yeah.
-1 < -1/2 < 0 < 1/2 < 1
So choose -1,0,1 as test points
ah
When it asks me to find the asymptote how do I do that. It says lim y = 0 as x approaches -and + infinity, so that the asymptote y = 0but I dont know why they do that
A little tip: e^(anything) is always a positive number
And this function has e^(-2x^2)
And let me just say this
e^(-inf)=0
e^inf is also 0 so asymptote is y=0
No
e^(inf) is inf
But the power of e is always negative here
So as we go to plus or minus infinity, we get e^(-inf)
So yeah the asymptotic is 0 because the function gets arbitrarily close to 0 on both ends but never achieves it
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ok so i followed the formula and i did
x (smallest number) , x-2 , x+2
then i made it into an equation doing
x + x+2 + x-2
and im currently stuck at 3x =0
Where does what you wrote come from then
Lets think logically instead
that for positives
Shall we?
.
i used the wrong formula
sure
There is no need for “any formula”
If x is an integer what is the next integer?
How can you write that in terms of x
if x is an integer, what number comes after x?
another integer?
2 ?
no
So what comes after x?
x +1?
good
Yes
and after x+1?
Can you solve it now?
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so far im at
E= 2 (2y) -3
basically im stuck at 4y-3