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The line y = x+1 intersects the curve y = x^2 +x-3 at 2 points.Find the coordinates of the 2 points
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hi
i just have a question
you know how you conjugate when u wanna verify trig identities sometimes
lmfao
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what generation
you haven’t even posted a question dawg
yes i have
just body shamed me…
you know how you conjugate when u wanna verify trig identities sometimes
yes.
conjugates are relevant in many questions related to verifying identities
okay my main concern is
im not sure on when you are supposed to conjugate
consider
c^2 = a^2 + b^2
c^2 - a^2 = b^2
(c-a)(c+a) = b^2
conjugates will usually be helpful if you have (c-a) or (c+a) present
I guess one example I can think of is if you think back to difference of 2 squares: x^2 - y^2 = (x + y)(x - y)
there are some trig identities that involve sums or difference of two squares, like for example
cos^2 x - sin^2 x = cos 2x
maybe you see you have (cos x + sin x) and you think you might wanna transform that for some reason into cos 2x and you multiply both sides by (cos x - sin x) to get the above identity and be able to apply it.
you might also be able to apply stuff like sin^2 x + cos^2 x if you move quantities around from one side to the other of the equation and signs are changing, so i'd say if you are familiar with the couple basic identities that involves differences and squares of sums you can often "smell these out"
you can't just say perchance
💀
why the hell are u talking here
i had a feeling someone was gonna say smth ab that
buddy
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@stone forge Has your question been resolved?
conjuate when a pythagorean trig identity is applicable/relevant
alr
i think i got it
ty
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Find the inverse of $f(x) = \frac{3x}{2x^2 - 18}$. So we have that \begin{align*} \frac{3x}{2x^2 - 18} &= y \ 3x &= y(2x^2 - 18) \ 3x &= 2y(x + 3)(x - 3)\end{align*} but all this doesn't seem very helpful
I also thought about dividing by x right away
But having $\frac{3}{2x - \frac{18}{x}}$ doens't seem very helpful either
Just expand
It's a quadratic in x
What do you mean, where?
You wrote 3 lines of computation
You can find where
$3x = 2x^2y - 18y$
You must mean that?
Hm
Oh, so you'd just solve for x with the quadratic formula?
yeah
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✅
So I got $\overline f(x) = \frac{3 \pm 3\sqrt{1 + 16x^2}}{4x}$. So here, we don't have to decide which one to pick, the $+$ or $-$ version?
Also, the domain of $f$ is $\mathbb R \setminus {3, -3}$ but our functions don't cover $0$, do they
So did we really find the inverse?
you pick both
it's +-
wdym?
if you mean the domains dont match, then they arent supposed to. the domain of a function is the range of its inverse function
Exactly
But 0 is not in the range
We'd have to introduce a second function, right?
A function maps an x-value to a single y-value
Not two
it is
if you conssider the limit
then f^-1 (0) = 0
right well i just noticed you mentioned the domain of f is R \ {3, -3} so you would only consider the plus
since the range of f^-1 would then have to be the domain of f
and also if you consider that domain of f then it doesnt have 0 in its range either, and f^-1 doesnt have 0 in its domain either, so it matches
,w range (3 + 3sqrt(1 + 16x^2))/(4x)
(-3, 3) is missing
,w range (3 - 3sqrt(1 + 16x^2))/(4x)
it is supposed to be
No, I mean R without the value 3 and without the value -3 with that
ah
It's perfectly fine to have 0 as the argument
It'd be f(0) = 0/-18 = 0
i thought you were just defining the function to have that domain
So 0 should be in the domain of f
my bad
I had to determine the largest domain on which f had an inverse
well if your original function isnt 1-1, your inverse wouldnt be either, now, would it?
if you exclude the entire (-3,3) interval then the function is 1-1
but right now it isnt
I used the first-derivative method
$f'(x) = -6 \cdot \frac{x^2 + 9}{4(x+3)^2(x-3)^2}$ I got
And that's negative on its entire domain
decreasing is not the same as 1-1
So f is 1-1 there
If it's decreasing the whole time it should be 1-1?
Oh wait
The -3 and 3 cause the problems here
It "jumps up"
it has a discontinuity at x = -3, for example, so it can go back up and decrease from a high value
yes
that's why i thought you excluded the whole interval
since that makes it 1-1
How do you know?
it removes the part where the function "jumps up" and decreases from a high value
so now it just purely decreases the entire time
But just looking at the derivative, you can't really tell when it will be at a high value
So you imagined its graph?
looking at the function, you can
think of it's behaviour just before -3 and just after 3
highly negative before -3 and highly positive after 3
so it jumps from decreasing and negative to decreasing and positive
implying it is 1-1
Is there a purely algebraic way?
Maybe using $f(x_1) = f(x_2)$
ig after you show f is decreasing you can just show that f is negative for x < -3 and positive for x > 3
this looks unnecessarily painful
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$U_0=2 \ U{n+1}=\frac{1}{U_n}+\frac{U_n}{2}
\text{prove that }\forall \ n \ in \ \mathbb{N} \ U_n>\sqrt{2}}$
brahim3579
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how can i slove it
How can there be $U_0$ then?
Roman_Garland
U_0 is the first terme
?
then n cannot be 0?
Bc Natural numbers starts with 1?
does it start with 0 in here?
its always start with 0
0 is a decimal number? absolutely not
$U_0=2 \ U{n+1}=\frac{1}{U_n}+\frac{U_n}{2}
\text{prove that }\forall \ n \ in \ \mathbb{N} \ U_n>\sqrt{2}}$
someone can helps here
brahim3579
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<@&286206848099549185>
Prove that U_n is always less than sqrt(2) and then is always equal to sqrt(2)
@cunning flower
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Can someone please help me with this question (it’s translated from German to English and there is a picture which shows the graph needed) Fig. 1 shows the graph of the derivative function f' of a function f. Which of the following statements are correct? Justify your answers.
A: The function f is monotonously falling in the interval [0; 2].
B: The function f has at the point x = - 1 a
Extremum.
C: The graph of f has a low point and a high point.
D: For all x in the interval [- 2; 0] applies f (x) > 0.
E: The function f" meets the X-axis at the point x = -1
If possible can you explain how to do in future problems
A: Monotoniesatz. Das besagt, dass die Funktion streng monoton fallend ist, wenn die Ableitung negativ ist
B: Was musst du denn prüfen, um herauszufinden, ob irgendwo ein Maximum oder Minimum vorliegt? ||Notwendige Bedingung: f'(x) = 0 + Hinreichende Bedingung: f''(x) > 0 bzw. f''(x) < 0 oder Vorzeichenwechsel von f'||
C: analog zu B
D: Welche Information geht beim Ableiten "verloren"? Denk an f(x) = x + 10000000 -> f'(x) = 1
E: Was bedeutet die Ableitung? f'' ist ja nur die Ableitung von f', was gegeben ist
Wie darf ich verstehen, dass die Ableitung Negativ oder Positiv ist, also von der X-Achse gesehen negativ oder wie? (Bezüglich A)
Der Graph, der gegeben ist, ist schon die Ableitung, also schaust du einfach, ob es da unterhalb der x-Achse liegt (wenn ja, dann ist es negativ)
Würde also f(x) so aussehen?
Ja, wobei es jede Verschiebung in y-Richtung haben könnte, die Information geht beim Ableiten ja veloren
Z.B. könntest du mit x^2 + 100 anfangen, die Ableitung ist dann 2x und wenn du dann versuchst, nur anhand 2x wieder auf die Originalfunktion zu kommen, hast du x^2, aber die + 100 ist verlorengegangen
Daher sagt man + C beim integrieren
Aber für diese Aufgabe musst du den Graphen nicht zeichnen
Ich weiß aber ich habe keine Ahnung wie man aus der Ableitung der Ursprungs Funktion Informationen entnimmt, dass ist mir jetzt deutlich klarer geworden. Die Lösungen haben wir nämlich auch nichts gebracht.
Und noch eine Frage zu E warum hat f“(x) eine nullstelle bei -1?
Wenn du die Tangente an f' bei x = -1 anlegst, dann ist die waagerecht, also ist die Ableitung von f' (also f'') dort 0
Die Funktion aus der Ableitungsfunktion zu zeichnen macht man normalerweise bei der Integralrechnung, hier reicht es, wenn du anwendest, was du darüber weißt, wie man ein Maximum oder Minimum einer Funktion findet
Du kannst ja mal versuchen, die Sachen, die ich am Anfang geschrieben habe, durchzugehen und wenn etwas unklar ist, kannst du ja fragen
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What’s happening with my inequality? I’m messing it up
How did x + 3 > 0 turn into x < -3
well thats supposed to be the answer
The exercise is to determine the domain, right?
,w domain (x-4)/(sqrt(x^2 + x - 6))
Ok, the solution is right, let's see where the mistake is
It's not necessary that both are positive
do you know wavy curve method
I prefer to imagine this as a parabola
(x+3)(x-2) has its zeros at x = -3 and x = 2
And it's opened upwards
So it will be positive on (-infty, -3) and on (2, infty)
ok let me think
tbh i dont really get what this is saying
This way is much faster than the algebraic one
i have to show my work for my midterm though ;-;
if you wanna go with the agebraic method just take the union set of the two possibilities
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Depends on what's meant by that
Am I not showing my working here?
ok gotcha
Unless your teacher told you to do it algebraically
(in which case you could tell him this way is faster when you have a quadratic and he should allow you to use this..)
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your final equation doesnt pass through the origin
put (0,0) in the final equation, it's not resulting a 0
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On the sides AC and BC of a triangle ABC, isosceles on the base AB, consider two points P and Q respectively, such that the angle CPQ is equal to the angle ABC. just need help with this really quickly
What do you have to get for the result?
@paper swan
that it is parallel
What is parallel ?
oh mb it didn't send the whole question
you mean AB and PQ is parallel?
yes yes
should they have to?
yes they shold be parallel
please show me the full question
Good. Observe that angle C is common for both.
Then angle CQP and angle CAB are also equal.
Do you have any geometrical conditions to show that two lines are parallel?
Since the angles subtended to a given line by two different lines are same, the two lines are parallel.
oh is that a theorem
It's not, actually. It's a simple observation.
If the other set of angles was not equal, we couldn't have said anything.
mhh
They basically wouldnt have been parallel.
would you have been able to do it without the drawing or nah
I would have been. The question gave me enough data to be able to draw it myself.
yeah but what if you couldn't draw it
my prof tells us that the drawing is there just to understand and you can't prove it just by observing the drawing but gotta write the proof
Tell your professor, in geometry, a drawing always comes first, even without the provision of data. Then comes the data itself.
I think angle CQP is same as angle CBA is enough for parallel-ness
No. What is CPQ was not equal to CAB ?
they are corresponding angles
Then the lines would be intersecting. See @paper swan this is why figures are important.

yeahh you're right
so how anout this one
In a triangle ABC, let BP be the bisector of the angle B. From P draw the parallel to BC; call Q the point in which meet the side AB. Always from P draw the parallel to AB until it meets the BC side. Prove that the triangle PBQ is congruent to the triangle PBR
Okay don't give a figure now.
alright
Yeah exactly.
How is it made ?
Perpendicular subtending. Random intersection?
How is it?
r is the point that meets CB
then PR is parallel to AB?
@paper swan
with BP in common
oh they're congruent because all their angles are?
should include that BP is in common, so ASA congruence
I still think CQP is same as CBA, as CQP=CBA=CAB
Haa that'll be there due to the isosceles property. But we were discussing what if it wasn't isosceles ?
yeah in the first question it is given it is isosceles
could you explain to me this better rq
because this doesnt ensure that they are parallel if no isosceles
I think the focus of what I was talking is different from what you understanded as. My fault, I am sorry
Have you learned any specific conditions to show that two lines are parallel?
If two lines cut by a transversal form with it:
two alternate (internal or external) equal angles, or
two equal corresponding angles, or
two additional conjugate angles (internal or external),
the two linesa re parallel
i learned this
I am not 100% sure on what solomaniac wanted to say, but I think he wanted to show that CPA=CAB and CQP=CBA
What I wanted to say is as CQP=CBA, two lines are parallel because they are two corresponding angles, and they have same angle
yeah the two lines are parallel because when cut with a transversal they form equal corrisponding angles
yeah you're right
I think me and solomaniac had different axiom to show parallel-ness
no big problem I guess
Sorry for confusion again.
@paper swan Do you have any other questions?
yes
so they have bp in common
and what else to determine they're congruent?
yeah when two triangles have a side in common and the two angles on that side are congruent
so how do we prove that
To add more QBP is same as RBP because BP is angle bisector
So QBP=RBP, BP in common and QPB=RPB
i don't understand how you can prove that QBP = RBP
so because they form alternate internal angles?
or that doesn't have anything to do with it
ah okay okay
Actually you dont have to say QBP=RBP for congruence
not necessary
QBP=RPB(alternal angle), QPB=RBP(alternal angle) and BP in common
so two angles, and side between those two angle is all congruent
which means ASA congruence for triangle
so because they are alternate angles?
yes
this with BP in common is enough for congruence
yeah but it says that bp is the bisector of just the angle b
not of the angle p
But as question is asking for PBQ and PBR, using bisection is appropriate now I think
what do you mean?
angle B is angle QBR
yes
bp is the bisector of angle QBR
and it divides it in half forming two congruete angles
but what about angle QPR
how do you know that it is also the bisector of that angle
As I know when writing dowm congruence, the order of triangle name is important
because QPB=PBR=QBP=BPR
alternal,bisection,alternal for equalness
yeah but how do you know that QPB=PBR=QBP=BPR
QPB=PBR for same alternate angle
PBR=QBP for bisecting QBR with BP
QBP=BPR for same alternate angle
ohh okay yeah now i get it
can you help me with one last thing?
okay
Given two parallel lines r and t, and a transversal t that meets the line r in P and the line s in Q, draw a line through the midpoint M of PQ that meets r in R and s in S. Prove that PR = SQ
Also ASA congruence
MP=MQ
RPM=SQP
RMP=SMQ
so two triangles are congruent
whicb means PR and QS should be same in length^
yes
yes
what about this
alternal angle
ohh right
they have same angle because r and s is parallel
"Given two parallel lines r and s,..." in your question
ohh mb it was supposed to be a t
i thought of something like this
the angles QMS and RMP are congruent because they're opposite
you are right. Only angles are not enough though. IMO It's good to look for at least one side congruence
if all three angles are same, but dont know about sides, then you say those two triangles are similar
but not enough for congruent
np
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Help
Yeah they are. You haven't understood what the question was asking.
It was asking $5^+, 6^-$
Solomaniac
Ik that
As for f, both the limits of $6^+, 6^-$ are going to -infinity.
Solomaniac
How
It looks like 6- doesn’t even go to 1
Same for 5+
6- is going to -infinity.
Same for 5+
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"(The old man in the box) A cubic box has a corner at the origin and edges OA, OB
and OC with others in the points A = (2, −2, 1), B = (1, 2, 2) and C =
(−2, −1, 2). A dot-shaped old man is at the point with coordinates
(0.9, −0.9, 4.5). Is the old man in the drawer?
Tip: Transfer to a suitable new base. Rephrase the question 'lie in the drawer' in ¨
algebraic terms. What finesse does the change to a new ON base offer?"
does anyone know how to solve this?
@random olive Has your question been resolved?
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why is this wrong?
@dapper wing Has your question been resolved?
ty
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i am confused about this question i found the derivative
do i just equal the derivative to 0
You'll need to find dy/dx before anything else
But yeah, dy/dx = 0 at those points
but i does not give me any points
Correct, you've got to find them
@stray timber Has your question been resolved?
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how to solve this
how much did he drive from 8:00 am to 1:00 pm?
how many kilometers
uhh
5
yes
do you know the speed formula?
distance over time?
yes
ok
you have distance, you have time. result will be your answer
81
can u help with another one
yes
24
yea
what's the formula for probability?
or like calculate the probability of drawing a red marble
uhh
without adding new ones or anything
8/24
yes
let n be the number you need to add
so you get $\frac{8+n}{24+n}=\frac{3}{5}$
artemetra
multiply 8+n times 5?
what's lhs
left hand side
72n/40n?
huh?
you should do $5(8+n)=3(24+n)$
artemetra
that's what i meant by cross-multiply
ight lemme solve
wait how does 5 end up on the left side
oh nvm
u got rid of both denominators
yes
no
lemme think
subtract 40 to put on right side then divide 3m
3n*
5n/3n=32
i thibk i messed up
wait
5n=96n
n=96n/5
no
dammit
subtract 3n from both sides
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If we let $\xi$ be random variable which denotes amount of points on the dice, then $E\xi^2=1^2P(1)+2^2P(4)$?
kitten
is that the q? because that doesnt seem correct. what about the other options:2,3,5,6?
Isn't P(3^2) = 0 and on because we have 6-sides dice? 
No. We aren't squaring \zeta inside the probability.
$$E[\zeta^2] = 1^2 P(1) + 2^2 P(2) + 3^2 P(3) + 4^2 P(4)+5^2 P(5) + 6^2 P(6)$$
swimmingland
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Sure thing! 🙂
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Help
U can move around any of these boxes
@dark idol Has your question been resolved?
Hey
What
how can i help
Idk how to do this
please dont spam us
IDK
NOOOO
BrO ThAT tO HArD
It's the hardest question in the world
YEAH UR RIGHT
WE ARE GENUISES
IK
Ok so u guys don’t know it either
Let me check
Its ask the teacher for extra credit
lol
@dark idol
What grade are you
Idk why that’s there
Joke anwser
Ok so how I do it
What grade are you, and what math class is this
It’s calculus college
Bruh
Im only grade 11
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I don't understand the solution. Why are they using inclusion exclusion for 4-sets, but getting so few terms? There should be 15 terms to work out
so, there is a problem with the solution?
I see they have grouped them now, and that there is 4 + 4 choose 2 + 4 choose 3 = 14 terms ...
i'm not sure, i would say yes
is there another approach than inclusion exclusion to this problem
sure, you can just add 3 terms
?
probability of an ace and king of the same suit in a 7 card draw from 52 standard card deck
can we just compute a conditional probability maybe
hmm no maybe that is harder
maybe I have a skill issue since I didnt try to group the terms like the solution did which made the work more expensive for me
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$81\int :sec^5\theta -sec^3\theta :d\theta$
putridplanet
i know this is a dumb question but you can't just subtract the sec^3 from sec^5 like that to get sec^2 because you are taking the integral of both
that would only work if there was no integral
right ?
ok but that would just make the answer tan +c
and my teacher didn't do it that way she took the individual integral of both
oh i thought you said you could
ok
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- Question: Complete the table so that sine theta is expressed in terms of the functions given across the top. (Cot theta)
my work so far
I am so confused on what this even wants me to do
I know to use trig identities but like idek what to do other that 1/cos
these are my options
more of what i tried
im actually working on the sec one first my bad
<@&286206848099549185>
do i ping at 15 min intervals?
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im wondering if i can cancel out the (x + 3) in the numerator and denominator. Usually it would be obvious but there is a coefficiant of 2 in the denominator and i dont know if that matters or not. Can anyone let me know if its still ok to cancel out the (x + 3)?
i suppose you can then
you can cancel them
ok
if youre doing graph stuff, just keep in mind that if x is -3 you have a hole and its undefined there
since its a removable discontinuity
yeah Im very confused on the hole thing
a hole happens when the function is undefined at a point but its limit has a value there
if it cancels out its a hole?
in a limit the x-3 will cancel
so the limit is defined at -3, but the function isnt
hence a hole
thats why i meant be careful in cancelling
context is important
now when i find the verticle asymptotes
do i keep the x + 3
or would it only be 1 asymptote then
Right now this is all I have
would just be the x-3
we know that (x+3) gives us a hole rather than an asymptote, so just the x-2
you want the limit to be undefined
the x+3 disappears in limits
so what do i put for holes
function undefined and limit defined
Do I just write the x + 3?
see where the function is undefined, check if the limit is or not
I remember my teacher showed us some equation but I don’t remember it
if it is then its a hole, if its not then its an asymptote
so if im cancelling out x + 3
is the hole x - 3 or x + 3
i mean x = 3
or x = -3
thats how my teacher wants us to write it
see where the function is undefined:+3 and -3
look at the limits, x+3 cancels out, and so the limit at -3 is defined, this must then be a hole
look at +3, the limit is also undefined since x-3 doesnt cancel, this is an asymptote
hole: f undefined, lim defined
asymp: f undefined, lim undefined
when i put the equation in my calculator both -3 and 3 are undefined
does that mean they are both holes?
this is as simple as i can put it really
yes f is undefined at +3 and -3, but the limits arent necessarily
ok
my teacher never told us what a limit is
or at least she must havbe explained it differently
So i dont reallyt know what you mean when you are talking about limits
oh, you dont know limits
okay, if the part that makes the function undefined at a point can cancel out, then that is a hole, if it cant then its an asymptote
-3 is a hole yes
you lost me there
i canceled out the (x + 3)
x+3 doesnt change to x=-3
but i canceled the x + 3 and you said x -3 is a hole
you need to stop writing things like this, its confusing
x=-3 is a hole yes because solving (x+3)=0 gives x=-3 and the (x+3) cancels in the function
you lost me at the word 'changes' because it makes no sense
ok sorry
if you mean x=-3 then write that, if youre referring to the x-3 in the function then write x-3
there has to be distinction
this is how my teacher taught us to solve holes
um, what was the original function
okay, that makes sense, i very much dont like how its written though
that last part is not f(x)
its a different function
but yeah, theres a hole at 0, because the function is undefined but the part making it so can cancel
hold on, actually this is just nonsense
it would be fine if using limits but this isnt being done
the point (0,2) is not even part of f
sure theres a hole at 0 but saying f=-2 there?? Why are they doing that
Dude I have no idea this is for a grade though honestly I just want to get a good grade
I barely even understand the mechanics of this
please dont write that f(-3) is that
its fine to say the hole is at that point you found, but dont say that its the value of f there
so what do i put
its a notation issue, it doesnt make sense without using limits
you can say the hole is located at (-3,-16/(-12)) ie (-3,4/3)
just dont say f(-3)=4/3
if you want to be classy, say
$$\lim_{x\to{-3}} f(x) =\lim_{x\to{-3}} \frac{3x-4}{2(x-3)}= \frac{4}{3}$$
AℤØ
that would be the most correct
Is there supposed to be 2 separate or did I graph it wrong
Yeah I’m a sophomore just trying to get a good grade on this
Ok but is the 2 separate lines ok
Ok
I’m confused on how to graph this
Like on paper
I need to use that x and y chart
And idk which values to pick
essentially just this, but put the hollow circle on -3
0 is essential, the rest you can just pick at random
but id label your axes first
might help in choosing
3 is the asymptote
Ok does that matter when I graph
you can see on the right it goes up, check some value like 3.1 or something on the left maybe check 2.9
Are these values ok
instead of error, write undefined
put those can work
you dont have space on your graph to get to 5 though
you really want some closer points the the undefined bits to see the behavior there
okay okay
you havent labeled your axes with any numbers
no one can tell the scale
but its definitely wrong anyway, your asymptote isnt vertical
thats important, itll help to actually mark where x=3 accurately is
Well idk how to fix it I checked every step
It’s getting late where I am
Honestly I’m trying to finish this
you need to label your axes, i told you
you cant make an accurate graph if you dont know where your values are
the function cant cross the line x=3 at any point

i presume youve seen the rational root theorem if this came up
probably
i honestly had no idea what was going on during this
i know the rest pretty well but this possible rational roots thing
i dont get it
this is an overview and example
actually ignore that its wrong oops
this one is fine
so you divide the factors of the first coefficient with the factors of the last one?
and thats all the possible ones
factors of the constant by the factors of the coefficient of highest order x yeah
part b will probably involve some polynomial division of some form
so what do i do with all those possible ones
i think i remember my teacher talking about substituting but i may be wrong
you sub them all into the polynomial to see which ones are actually roots
yeah
damn i gotta substitute all of those
heh
do i need to do the +- seperately
yup
wow just realised this gave you all your roots lol
oh well, at least its relevant
for my roots
i got 1, -1/2, 1/3, 3
well at least its 4 roots
no idea if its right or not
next question
😭
looks worse than it is, just factorise everything you possibly can
first i need to swap the numerator and denomerator of the 2nd part right
and change it to multiply
sure
problem is so long even photomath couldnt recognize it
i know how to do this its just going to take me so long and i want to go sleep
im just going to skip for now
@latent walrus isnt this just horizontal asymptote?
or is there something more
Here’s my work
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i dont where to go after i put it into the matrix format
ik im supposed to get 3 0s and lke check but like what is the question asking
im just confused in general
you must determine range of k
so will it be like k>n?
wdym
oh
using the answers
how do i solve
i dont get
how do get rid of the k^2
using formula
which?
Matrix
?? trheres formual
are you university student?
oh, it is formula which can learn in university
how do i relate that tgo this?
i will think some other ways
ah ic ic? i dont think i will be able to remember it
thanks
oh, i think it is not difficult problem.
this problem is which type in your textbook
oh
so this problem means that get appropriate k to not exist proper a, b, c
right?
i think determinant value of matrix should be 0
ok... so this is
the system
of eqn
what should i do with it?
substitute kc?
solve for kc?
substitute
and also substitue ak^2
so should i solve for ak^2
and then sub it into q1 or 2
u gotta sovle these 3 equations?
-2 and 2 is all ok?
what is uni stuff?
i think there might be more solutions, i guess 4 solutions, but it is too difficult to calculate them
you only use gaussian elimination
and finally you can get:
k^3-4k | 2k^3- 6k+4
so solution will be +2 or -2
got it?
hey @gritty grotto
yuh
eq1 remains unchanged
yeah i just write it out
you must do eq3 - eq1*(4/k^2)
wdym?
eq2-eq3?
... ... ...
0 ... ...
0 0 ...
eq3-eq2?
how do i get that im sorry so sorry
eq3 - eq2*(2+4/k)/2k
wait