#help-27
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Remember that you just need to find secx
yeah
do you just bring the secant over?
oh but that would make it a negative
idk
You should try to turn tan^2(x) into sec^2(x)
uhhhh
do you just bring the tangent over to the secant?
or is there some factoring stuff cause I'll be honest I don't remember anything about factoring except that you can eliminate things in common
Actually you can try adding 1 to both sides of the equation
I thought that was a chemistry thing
x=y
x+1=y+1
are they the same thing
yeah
Add 1 to both sides
And it’s correct right?
like as in would it still = to x?
Are both sides still equal
Adding and subtracting numbers to both sides of the equation
It is still true
Back to the question:
$\tan^2{\theta} = 3$
Afi
What happens when we add 1 to both sides
yes
$sec^2\theta = 1 + tan^2\theta$
Afi
if you add to something you have to add to both sides?
1+sec^2=2+tan^2
oh wait
now are you allowed to subtract?
it'll be negative though
uh
$sec^2\theta = 1 + tan^2\theta$
$1+tan^2\theta = 4$
Afi
What conclusion can you make from these?
$sec^2\theta = 1 + tan^2\theta = 4$
Afi
We have
$\sec^2\theta = 4$
Correct?
Afi
We can just ignore the tangent
mmm okay
Since sec^2 x = 1 + tan^2 x
okay
1+tan^2 = 4?
We essentially replace the whole left hand side with sec^2
uh
Ok I wanna ask which part do you not understand
like a lot of it honestly
Feel like the numbers are jumping from one thing to another
I don't understand how it went from sec^2 x = 1+tan^2 to 1+tan^2=4
since it seems like the right went to the left and sec^2 replaced by a 4
Lemme ask you
If x=y and y=z
Is x=z?
er
I'm not a mathematician so I don't really know but assuming that by = you mean they're the same functions then yeah
they're just variables
This applies to your case
sec^2 = 1 + tan^2 and 1 + tan^2 = 4
Then we have sec^2 = 4
x is sec^2
y is 1+tan^2
z is 4
Wdym by y values
Yes
Sorry for the ambiguity
no problem
Any questions?
nope I think I understand it a lot better now but I think i'd still like to polish it a little bit by watching some videos on it
what would you call what we just did
?
Ah
oh yeah it's been a while since i've done anything like that
but thanks
Ok so we have $\sec^2\theta = 4$
Afi
Solve for secant
do you want to find this
or this
sec^2-tan^2=1 and tan^2=3 so isn't that really just 3-1?
What we have done:
tan^2x=3
We add 1 to both sides of the equation and get
1+tan^2x = 4
Rewrite 1+tan^2x as sec^2x (since 1+tan^2x = sec^2x)
sec^2x = 4
is the 4th line plugging in an equation
Correct
Divide the Pythagorean identity by cos^2 to see it
sec^2(theta) = 1+tan^2(theta) ?
Yes
alright
kinda dumb question but where did the secant thing originally come in from cause i think that's the thing causing a lot of confusion
Try to do this
divide the formula or what we have right now
This identity:
Sin^2x + Cos^2x =1
oh I see
Remind you that secx is 1/cosx
would the new cos^2 come in from the side with the = 1?
or do we use the cos^2 we have
and divide the 1 by it
oh but then it's squared
so don't we have to convert it back to cosx
ohhh
I see
okay
1/cos^2 turns into secant and sin^2/cos^ turns into tangent
cos^2/cos^2 turns into 1 because they're like terms right?
idk how this ends out but does secant subtract tangent to get 1
I'm new to the the trig function things so I don't really know
tan^2-secant^2+1
wait no
sec^2-tan^2
?
since that is the formula from earlier
sec^2-tan^2=1 is true
idk how dependable it is
?
wdym
the secant goes to the other side right
with the tangent
does it turn into a 1?
Wdym by that
the formula i knew prior to this
State the formula
No no this is true
You don’t need to
Mmm
tan^2x=3
We add 1 to both sides of the equation and get
1+tan^2x = 4
Rewrite 1+tan^2x as sec^2x (since 1+tan^2x = sec^2x)
sec^2x = 4
We just replace 1+tan^2 with sec^2
oh I see
How would you solve for secant after these steps?
what negative value?
Given x^2=4
What are the values of x?
Nope it’s just all the possible values that satisfy the equation
Since if we call secx = -2
Then sec^2x is still 4
oh I see
not sure but I'm pretty sure it's only asking for one value which is 2
let me see
oh
yeah
nope but do you mind writing a script for all of this so I can use this in reference I understood it but I think I just need practice on it
I don't want to miss something then screw it up because of that lol
Perhaps we can do that in DM
Do you mind?
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ok so i understand 15. and that it's false
because for example, sin (390 degrees) is positive and half of it is 195 degreees
and sin(195 degrees) is negative
right
but for 16., the answer is also false
but im not able to find an example like that
hmm
Take anything between 90 to 180 degrees
one sec lemme try
lets do cos(120)
which is equal to -1/2
and then lets now do
half of it
cos(60)
1/2
oh i see lol
that was an easy proof
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i'm stuck trying to find the points of inflection
because i run into a divide by zero when plugging in the interval values into f(x). (they are asymptotes) how do i show my work in finding points of inflection? if there even are any? can there just be none?
@pulsar relic Has your question been resolved?
You need to look at what your definition of an inflection point is. Usually you only call a point (c,f(c)) an inflection point if f(x) is continuous at c. I don't know if any books do it any other way.
If you have a discontinuity like at -2, then even though it may change concavity, it won't be an inflection point.
inflection point is when the concavity changes direction (?). what you said sounds more right though
That's not a mathematical definition
i havent taken any classes on proof-ing things i just regurgitate things i read in the course material 😭 and this wasnt really explained in words or examples
It probably was and you ignored it
thanks for the help
still need someone to explain it to me though how to answer the problem
I believe an inflection point is when the second derivative is equal to 0 or undefined and it changes sign or the function changes concavity
i've calculated the undefined intervals, and the concavity changes between those intervals but there isnt exactly a point of inflection for this function. I dont know how to show that though
I did some research and I think I got the answer now
For an inflection point to exist the original function must be continuous
At x = 2 and -2 the original function is not continuous
Therefore it has no inflection points I believe
alright, i'll use this explanation, confirmed by 2 people makes me feel more confident about it 😅
Here is where I looked at
See the explanation section below. A point of inflection is a point on the graph at which the concavity of the graph changes. If a function is undefined at some value of x, there can be no inflection point. However, concavity can change as we pass, left to right across an x values for which the function is undefined. Example f(x) = 1/x is concav...
i kinda get it more now with that extra graph example, ty 🙂
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<@&268886789983436800>
it would be better if you post relevant questions.
He's trolling
@odd mantle Has your question been resolved?
<@&268886789983436800> ??
2+2 = 4 day mute, please do not troll in help channels
they already left I hate it here
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Hi, i want to reciprocate this function:
Sum( 1 to m-1 ) + n + 1 with m>n
if necessary i can prove that this function is bijective.
i tried to expand it, and work on it like a 2nd degree polynom but i have no idea how to use the inegality in it.
what do you mean with reciprocate? also can you post a picture of the function instead?
i want to found a function that can found m and n from an x
@onyx helm Has your question been resolved?
<@&286206848099549185>
@onyx helm Has your question been resolved?
such that its of this form?
well first of all
u need to find a transformation (function) that gives two unique m and n (integers ig) for some x
we can then put that in this to get the function u want
do u understand that?
nop
...
well u want to get 2 numbers from 1 number
and u need to do that in a unique way
because else it wont work for all m and n
thats called the inverse
yes but my function is bijective
okay i think i get it !
good
that is the sum
u need a bijective function that takes 2 numbers and spits out 1 number
does that make sense?
no i'm confuse
my function is a bijection that spits 1 number from 2
if i understant you tell me to fount a g(x) so i can have g(f(x))
that take 1 and spits 1 ?
カナヴ
correct?
yes
but u arent providing m or n
so u need a function
that takes x
and gives u m and n uniquely
it's for every m and n in N, m > n
so a function that do that ?
thats just the domain
but how i do a function that have 2 out ?
inverse of a 2-in 1-out function using vectors
what do u even need this for tho
for a program i'm doing
if u can provide me more context, i might be able to help find a better solution
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
yes, my "proof" of bijectivity tell the context:
Consider two list the first one is construct by associatting Letter to the natural number (the alphabet is for the exemple, but consider it infinite) so you associate A to 0, B to 1, C to 2 and so on...
The second is construct associatting every couple of letter to a natural.
we procede be expend the first list progresively
so when there is only A in the first list we can't form a list so the neutral élément is associated to 0
(that first part is not nessesary but it's most convenient)
BxA -> 1
CxA -> 2
CxB -> 3
DxA -> 4
DxB -> 5
and so on...
we took two letter from the first list and we assosiate m to the max value and n to the min value.
and we found that the function Sum( 1 to m-1) + n + 1, tell the position of the couple in the second list.
lemme read thru tbat
np
couple as in pair?
French
it's for pair a list of element
kk
(i'm looking at Vector-valued function, my solution might be here i guess)
ah no mb
f(m,n)
BRUH 💀
the inverse i search is a g(x) so
@onyx helm Has your question been resolved?
@onyx helm Has your question been resolved?
@onyx helm Salut, tu as encore besoin d'aide ?
salut, oui je veux bien
Ok, peux-tu expliquer en français ce que tu recherches plus exactement? Ça me paraissait flou
Tu cherches la réciproque d'une fonction?
oui
Tu peux écrire clairement sa définition (en incluant les arguments du domaine d'abord)?
Par exemple, f(m,n) si j'ai bien compris ?
Ok, et donc étant donné un nombre naturel x, tu cherches un couple (m,n), avec m>n, qui fera en sorte que f(m,n) = x?
oui exactement
Et tu as déjà démontré que c'était bijectif
oui
Ok ok
(je suis plus dispo dans 30m a moitier occuper atm)
Si tu prends un nombre x naturel (plus grand strictement que 0), il se situera forcément entre deux termes de la suite des sommes des entiers naturels: 1, 3, 6, 10, 15, 21, etc......
Tu dois prendre le plus grand entier de cette suite qui est plus petit ou égal à x, et ça te donnera la valeur m correspondante
ensuite, il faut aller ''chercher'' x avec le n
Ça peut s'écrire formellement mais c'est crucial d'abord de comprendre l'idée
oui tout a fait, c'est d'ailleurs l'idée que j'avais pour le résoudre avec un recursion de manière algorithmique, mais je sais pas comment faire de manière mathématiques
Tu veux dire, tu sais pas comment bien l'écrire?
nan, si je le fait avec un programme avec des boucles avec un condition qui check que l'entier est plus petit que x, ça je sais faire.
mais je veux trouvé une solution qui m'évite de faire des récursion, car c'est une fonction que je vais beaucoup appeler
En gros, étant donné x, tu veux une formule explicite pour m et n
sans faire de ''boucles''
exactement
Pas évident hein !
nop ^^
Pourquoi tu veux pas faire de boucles ?
par ce que c'est une fonction asser primaire de mon programe, et que ça va être appeler en masse et ça va alourdire le programe énormement
@onyx helm : si tu définis la fonction f(y) = y(y+1)/2
Alors étant donné x, la valeur m correspondante est donnée par la partie entière de f^(-1)(x)
et ça se calcule, f^(-1)(x)
f défini sur les réels positifs
et la valeur de n est ainsi donnée par x - f(m)
et tu as tes 2 formules
ouai je vais essayer, mais me semble qu'il faut quand même une condition pour vérifier une valeur
C'est-à-dire ?
un if qui check que f(m) est plus petit que l'entier x
Par définition de m, f(m) sera plus petit que x
toujours
pas besoin de if
ou égal à x
je vais essayer comme ça alors
Si tu calcules f^(-1)(x), tu devrais obtenir:
$f^{-1}(x) = \sqrt{2x + 1/4} - 1/2, \qquad x \geq 0$
Donc $m = \lfloor \sqrt{2x + 1/4} - 1/2 \rfloor$
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Hello
So my current thing is
So far I think I have one option correct
I tested f(-5) for it and it came out to 1 divided by 0 which is undefined
Im a little unsure about the rest
but f(-5) isn't undefined
pay close attention to the conditions on the right
for which piece to use
hmm
I believe the first box is correct, because as x approached -5 the denominator appraoched 0 making it lean towards infinity?
yes
hmm alright...
gimme a second to do some calculations
Wait I have a question
How is f(-5) defined?
I plugged in -5 for the top expression 1 / x + 5
why are you plugging -5 into the top expression
oh wait
pay close attention to the conditions on the right
for which piece to use
it says not equal to -5
oh wait no its the opposite
it is
thats what makes it defined
wdym by opposite
hold on just a moment
no nevermind, i just meant that when the function is equal to 1 when x = -5
yeh
im not sure what makes the limit finite, is it when it has a finite number it stops at?
hmmm
I feel the answer would be none of the above no?
wait nevermind
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How does R2 dot R1 + R1 dot R2 = 0 get to 2R2 dot R1 = 0?
Dot product is commutative
a dot b = b dot a
number / 2 = 0 implies number = 0
in real number multiplication, $2(ab) = (2a)b = a(2b) \ne(2a)(2b)$, similar reasoning applies here
cloud
thats true, i guess i still don't get what makes it 2R2 dot R1 and not 2R1 dot R2
unless those are the same thing?
They are the same thing.
oh wait, its the whole dot product times 2?
Yeah.
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If I have a solution set like that, is my dimension still 4?
dimension of what?
The solution set?
And i think it should be 1 because we only have one free variable right?
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this definitely seems solvable yes
unless i grossly misinterpret the problem
that is, by "iteration" i assume the problem refers to function composition
Yeah
What approach would you take?
Not the solution, i just need an approach bc im not sure where to start.
i probably poke around and examine the domain and range of the first few iterations
👍 thats smart. Thank you so much!
welcome 🙂
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How would I do 1200 is deposited into an account that earns 7% compounded monthly. How long would it take to reach 1398.23
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trying to solve this by setting the simplest term equal to a variable and changing the rest in terms of that same variable
only problem is I lack that math skill
so for example im trying to let sqrt(x+1) = a
what would the rest of the terms be equals to
in respect to a?
if it has a name or something so I can learn it, but I assume its basic algebra
I'm assuming that wouldn't work
Even the binomial approximation may work here
not allowed to (apparently not in the course)
i mean the binomial series is just a taylor series
then use binomial approximation.
woah ok intimidating to look at
$(1+x)^a= 1-ax$ is the binomial approximation
Why am. I here
try that
I remember my teacher going over this but instead having the numerator and denominator with a bunch of square roots
Why am. I here
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Perhaps try rephrasing your question?
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hm
$\sqrt{x+1}=(x+1)^{\frac{1}{2}}=1+\frac{1}{2}x?$
mj
I think so , going by wikipedia's defn
$\frac{1+0.5x-1+x}{4+1.5x-4+x}$
mj
$\frac{1+0.5x-(1+x)}{4+1.5x-(4+x)}$
mj
$\frac{-0.5x}{0.5x}$
this is equals to 1
wait i definetly did something wrong
ans is -2
,w limit of $\frac{\left(\sqrt{x+1}-\sqrt{\left(2x+1\right)}\right)}{\sqrt{3x+4}-\sqrt{2x+4}}$
yup, it's right!
no i meant
im wrong
by getting 1
it's supposed to be -2
oh
who's taylor and what is this series
mj
it's 4+ 3x/2
oh
nvm, that's 1.5
ok, sorry I have to go now, sorry if I misguided you
no worries lol
i figured out how to do this question
the intended way
just thought this was
interesting
Using rationalisation?
no using this taylor series
ah,ok
Just check if you've made a calculation error anywhere
this is not the right taylor series
how come
,, (1 + x)^\alpha \approx 1 + \alpha x
but this says nothing about (4 + x)^α
what equations
,, (4 + x)^{1/2} \approx 2 + \f14 x
$4(1+x)^{0.5}=4(1+0.5x)=4+2x?$
mj
i don't like your use of the equals sign here
apologies
the first = is most certainly not =
what would the answer be to this?
.occupied
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because your method is wrong
how come?
,, (4 + 3x)^{1/2} \approx 2 + \f34x
using the taylor series approximation
3*(1/2) is what your doing here?
ok tell me this
what do you do to get from point a to point b
starting with the 4 to 2
no you factor out the 4 to apply the (1 + x) approximation
ok great
so you h ave no
now
but wait
you have to apply the exponent
first
$(2+3x^{1/2})$
mj
ah im confused now lol
what did you do
that doesn't make sense
mb
you can't "apply" a sqrt to an expression like (4 + 3x)
ok but how would you factor out a 4
from something that has a power
being applied to it
,, \sqrt {4 + 3x} = \sqrt {4(1 + \tf34 x)}
shouldn't you apply the power first before factoring?
oh okay okay
I see
lol yea that makes more sense now that i think about it
so in our case $\sqrt{4+2x}=\sqrt{4(1+ \tfrac12 x)}$
wait a minute no
use \tfrac
mj
mj
$4(1+0.5(0.5)(x))$
mj
$(4(1+\tfrac14 x))$
mj
$4+x$
mj
you have to square root the 4 here
it'll be a 2
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When you graph a polynomial function, does the turning points must equal 1 less then the degree? or is 1 less then the degree the max amount of turning points the graph can have?
consider polynomial x^4
what is its degree?
how many turning points does it have?
1
and what is the degree of x^4 ?
4
does this answer your question, then?
welcome 🎉
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Can someone explain part B
We have this theorem
We would move f(x) and p(x) to the LHS
and take absolute values
I was more confused on how we would bound the term on the LHS tho
that taylors expression term
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how to do this problem
i tried to start but got to nowhere
i tried to get the torque or weight of the beam or something and then i didnt know what to do i dont know if i was meant to do
is T=1700N in the conditions?
and the length of that beam is 4.2m
yeah
is that the rotation point
no, that tit up point
?
what do i do with that point what r u saying im confused
the component force of T that paralled with this pink line u drew, let's say F1
satisfied F1*4.2m = 1300Nx3.8m
r u using the torques
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hi
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i think i messed up somewhere but im not sure what since there is no answer key
can someone check my work
a) is fine,
but then why are you using -1/12 for the slope in b)
idk i just remember seeing my teacher do the negative recipricol when doing the equation of the tangent
as those are perpendicular to the tangent
ohhh
yes. the slope of the tangent line is the same as the derivative at that point
we arent at derivatives yet i dont even know what that means
so the equation would be
12(x-2) + 15
o i think it worked
yipee
we arent at derivatives yet
you're pretty much being asked to apply the limit definition of the derivative to get the slope
not sure why they're not mentioning derivatives here
im in hs right now and we just started limits im pretty sure we do derivatives next
its worth looking up "limit definition of the deriative"
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quick question
can you define abs(x) as sqrt(x^2) instead of a piecewise function
... i mean it still being somehow a piecewise function
but still, is it valid?
Yes
That's absolutely valid
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This is 17.6
@stone stump
surely you have done similar questions of the type "given are some vector which span a space, find a basis of that space" before?
Nope, but is the first step getting it to RREF?
Why is 17.6 needed at all
well existence proof
always good to know that the thing you are looking for actually exists
Ah
\begin{align*} \mr{1 & 1 & 1 & 0 & 3 \ -1 & 0 & 1 & 1 & -1 \ 0 &1 & 2& 1 & 2 \ 1 & 2 & 3 & 2 & 4} &\sim
\mr{1 & 1 & 1 & 0 & 3 \
0 & 1 & 2 & 1 & 2 \
0 & 1 & 2 & 1 & 2 \
1 & 2 & 3 & 2 & 4} &&(I_2 \to I_2 + I_1)
\ &\sim
\mr{1 & 1 & 1 & 0 & 3 \
0 & 1 & 2 & 1 & 2 \
0 & 1 & 2 & 1 & 2 \
0 & 1 & 2 & 2 & 1} &&(I_4 \to I_4 - I_1)
\ &\sim
\mr{1 & 1 & 1 & 0 & 3 \
0 & 1 & 2 & 1 & 2 \
0 & 0 & 0 & 0 & 0 \
0 & 1 & 2 & 2 & 1} &&(I_3 \to I_3 - I_2)
\ &\sim
\mr{1 & 1 & 1 & 0 & 3 \
0 & 1 & 2 & 1 & 2 \
0 & 0 & 0 & 0 & 0 \
0 & 0 & 0 & 1 & -1} &&(I_4 \to I_4 - I_2)
\ &\sim
\mr{1 & 1 & 1 & 0 & 3 \
0 & 1 & 2 & 0 & 3 \
0 & 0 & 0 & 0 & 0 \
0 & 0 & 0 & 1 & -1} &&(I_2 \to I_2 - I_4)
\ &\sim
\mr{1 & 1 & 1 & 0 & 3 \
0 & 1 & 2 & 0 & 3 \
0 & 0 & 0 & 1 & -1 \
0 & 0 & 0 & 0 & 0} &&(I_3 \leftrightarrow I_4)
\ &\sim
\mr{1 & 0 & -1 & 0 & 0 \
0 & 1 & 2 & 0 & 3 \
0 & 0 & 0 & 1 & -1 \
0 & 0 & 0 & 0 & 0} &&(I_1 \to I_1 - I_2)
\end{align*}
So now, we pretty much found the base of the row space, right?
It's the individual rows
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Why?
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I don't get that
u dont get what?torques?
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this should be equal to exp(x) no??
yes
so thers a mistake
by using the property lim h->0 (e^h-1)/h = 1, u get e^x
yes
okay thanks !!
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is this right>?
and what about this one
can you show your work
do it again
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I'm still not sure what's wrong here
take -pi/3 and add pi to it to get the correct angle, since that's a half rotation
that's 2pi/3, not 5pi/3
How did you know that you have to add pi? Isn't that gonna land in the 2nd quadrant?
yes, but if you're in Q2, and r is negative, then you land in Q4
it flips the line 180 degrees
Oh nice
So, when picking the angle, i have to keep an eye on where the line is gonna land
And pick the angle that will make the line land on the quadrant that matches the cartesian coordinate
Right?
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Why is those equal why doing that
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this question giving me a serious headache
what approach do you take?
well, i can tell there is an infinite discontinuity at 0
or is that a jump one?
infinite
how do you tell that
division by zero with the numerator not ≠0
if the numerator =0 as well then it’d be a removable hole
jump occurs with piecewise functions
ah, the nmerator ok
think of it like a limit
if u divide any number by let’s say 0.000001
it’s going to be very large
and the smaller the denominator gets the larger the quotient gets
so are u aware of any algebraic techniques
wdym
im confused how to do this analytically
like guess and check?
no
i mean
im sure that works
but
it’s not a good habit
so what do I need to do
well u know it’s infinite correct
so it’s either going to go to positive infinity or negative infinity
I think I need to split it up and get limits of smaller portions, then get limit of the whole thing?
so what u can do
is determine the sign of the function before the discontinuity
which will determine if it approaches +infinity or negative infinity at the left or at the right
of the asymptote
I was so confused about this, thank you
so adding them will always be>0
so we only need to look at the sign of the denominator
also note
how would u determine the sign of the denominator
so e^2x-e^3x
wait, plug in 0 to numerator its 0?
wdym
if you plug in 0, numerator is 0 denominator is 0
yes
therefore infinite
because the denominator is 1-1=0
so
e^2x-e^3x
will this be positive or negative for x>0
so its positive infinity from right
no
its positive from right
think of it
negative left
like
(e^x)^2-(e^x)^3
the cubed will be larger than the square for x>0
if x<0 then it’s a negative exponent which makes it 1/e^2x + 1/e^3x
so its negative?
and here since the terms r in the denominator and e^3x>e^2x when u take the reciprocal or do 1/ it will be positive
so from the left it’s positive
from the right it’s negative
u could even plug in values in ur head if it makes more sense
let’s say x=1 which is >0
e^2 -e^3 is clearly negative
but if we did x=-1 which is <0
1/e^2 -1/e^3
since e^3>e^2 the reciprocal will be smaller
so 1/e^2>1/e^3 therefore it’s positive
hmm
from the left it’s positive lol
and right it’s negative
i’m not trying to just give u the answer
i’m trying to help u
understand it
aye
from the right
yeah I don't even know where to begin for this
yeah
which correspond to horizontal asymptotes
well plug in infinity for x
u get infinity in the numerator
and it won’t work
because u get -infinity in the denominator
so u have to use algebra
to simplify
to do this
divide by the highest degree
so divide each term in the fraction by e^3x
to simplify this to just constants
tell me what u get
for each term
when dividing each term by e^3x
highest in denominator?
highest in all terms? just the denominator?
^
you’ll see why we do this in a bit
just simplify first
like what’s 5e^x/e^3x
and 9e^3x/e^3x
and the same thing for the terms in the denominator
how do you divide exponents?
yeah i see
^
i have no idea, the terms are different
5 on top, 1 on bottom
5 is a constant multiple
also bottom has a constant in the exponent
…
it’s the same thing as saying e^x cubed
recall
(a^n)^m=a^n*m
so the answer i 5/e^2x?
we want it to be
just wait until u do all of them
i’ll explain after
once u have a new fraction
with everything simplified
so the 9 term is then just 9 after the division
yeah
what happens if we take the limit as x goes to infinity for those fraction terms
5/e^2x gets larger?
r u sure
e^2x goes to infinity
but 5/infinity is not infinity
what’s 5/100000000
it’s near zero yes
the larger the denominator gets the smaller the quotient gets
-9
because the two fraction terms go to zero
u get 9/-1 or -9
now what happens for negative infinity
with our same expression
with the fractions
no?