#help-42
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ok
so we have sin^3(x)
which means we can effectively use the power rule
do you know what that is?
yes
so
3sin^2(x)?
oh mb mb
so sin^4(x)/4
yeah
and check that it comes back out
ok ok thanks
do ya have any other questions mate?
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when I factor out 1/13 from 27/13 I get 27/ 169, but not 27
i’m doing smth wrong idk what
ℝαμΩℕωⅤ
thus factoring 1/13 out of that leaves you with 27
you're dividing the wrong way
oh
to see what you're left with, you want to divide
what you're starting with: 27/13
by what you're factoring out: 1/13
(27/13) / (1/13) = 27/13 * 13 = 27
relation between division and multiplication
Is it possible to do it through cross multiplication because I just don’t really understand what you sent because I don’t understand how I would be able to compute that on paper
okie ty
cross multiplication refers to manipulation of equations doing:
$$\frac pq = \frac rs \implies ps = qr$$
ℝαμΩℕωⅤ
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how do i solve this equation for Z5 (all the whole numbers group between 0 and 4 including both)?
do i do:
x^2 + 1 = 0 /+4
x^2 = 4
and then just plug in all the numbers 0<=x<=4 and see what works?
x*x mod 5 = 4, per the construction of Z5 as i know it (all possible reaminders of 5 group numbers)
yes that's correct
sorry didnt mean to type haha
but isnt that impractical? what if it was Z17, or anumber number group that's way bigger
i think this is not the correct way to solve this problem
since 5 is a prime number I think you can factorise this
$(x+2)(x-2)\equiv 0 (\text{mod 5})$
kheerii
so $x+2\equiv 0$ or $x-2\equiv 0$
kheerii
note however this ONLY WORKS if your base (in this case, 5) is prime
why?
i dont if it's not prime then it's not a field
but how does this matter? i mean what axiom
I'm not sure about the field theory aspect of it, so I can't help you there
I can tell you why it fails from a number theoretic standpoint
say you have $ab\equiv 0(\text{mod 10})$
kheerii
you can have $a\equiv 0$ or $b\equiv 0$
kheerii
but you can also have $a\equiv 2$ and $b\equiv 5$, this also gives you a valid solution
kheerii
that's why factorising doesn't work for non-prime bases
what are a and b here?
the two factors
we started from this equation
oh i see
but i dont understand how that's relevant
we can only conclude this because 5 is a prime number, that's what I was trying to explain to you
since it's not a*b, but either a*a or b*b
$$(x+2)(x-2)\equiv 0 (\text{mod 5})\implies x+2\equiv 0 \text{ or } x-2\equiv 0(\text{mod 5})$$ but $$(x+2)(x-2)\equiv 0 (\text{mod 10})\text{ does not imply } x+2\equiv 0 \text{ or } x-2\equiv 0(\text{mod 10})$$
kheerii
how not? i mean it does mod 10 on the LHS too
you're great at this
because, these are not the only possible cases
you can also have first factor = 2 and second factor = 5 for example
i dont see how?
okay maybe this specific case is a bad example
it probably isn't possible for this exact question
but I'm just telling you that you need to RULE OUT those cases separately
you cannot conclude this directly from that statement
i dont follow
i mean i can
since it's a square euqals something in Z(n)
heres an example
,, x^2 - 5x + 4 = (x - 1)(x - 4) \pmod {10}
it seems that you have the solutions x = 1 and x = 4
but you also have
[ x^2 - 5x + 4 = x^2 - 5x - 6 = (x + 1)(x - 6) \pmod {10} ]
so there is also x = -1 and x = 6
why is it like that?
because 10 has nontrivial factors
I get it's because the group of reminders Z_p is not a field because p is not prime
but what axiom is not working?
Z/10 is not a domain
Z/5 is a domain
a domain is where there are no zero divisors
in Z/10, there are zero divisors
2 divides 0, and 5 divides 0
whats a factor?
not native
alright so I understood
wdym?
10 | 2*x?
oh
I understand, so the axiom of only 1 resetting multiplication number doesn't exist here
i have no idea what that means
Z/10 satisfies all the axioms of a ring
it is in fact a perfectly fine commutative ring
it is not an integral domain however
but how would you solve then for:
x^2+1=0 (for Z_10)
you write it as x^2 - 9 = 0 and factor it into (x - 3)(x + 3)
so 10 divides (x - 3)(x + 3)
0a=0 (only one such number can be "0" type)
so if ab=0 then it's not a domain
then you have one of 10 | x - 3, 10 | x + 3, 2 | x - 3 and 5 | x + 3, or 2 | x + 3 and 5 | x - 3
so the only solution is 3?
thats the axiom of an integral domain
theres x = 3, x = -3 and no others
integral domain is?
a commutative domain
-3 is not a member of Z_10
yes it is
no
the equivalence class of -3 in Z/10 contains all the elements congurent to -3 mod 10
this includes elements like -3, -420693, 1337
I see
my bad
so these are the only solutions?
you can check directly that the other two options dont work
but if you allow -3 to be a solution, so is -13,-23,-33
since you're working with mod 10
those are all congruent to -3, and so is included in the x = -3 solution
but 3 is not congruent to -3, so x = 3 and x = -3 are distinct
yes i didn't realize that sorry
so then how would you solve this?
you factor
and you say either
- 10 | x - 1,
- 10 | x - 4,
- 5 | x - 1 and 2 | x - 4, or
- 5 | x - 4 and 2 | x - 1
this gives you the 4 solutions that i listed earlier
so it'll be 1,5,-1,6?
the 5 should be a 4
i guess another way is by using the chinese remainder theorem
(x - 1)(x - 4) = 0 mod 10 means (x - 1)(x - 4) = 0 mod 2 and 5
you solve the equivalence in both moduli and combine it together
I think I understand now
ty very much mate
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Is there way to find roots of cubic equation easily
Like there is [-b±√(b^2-4ac)]/2a for quadratic equation
@remote mural Has your question been resolved?
,w x^3+x+1=0 exact solution
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is there an easy way I could approach this question
because I have no clue how I would find 2 factors so that the two vectors are equal to v1
Just write the linear dependance
You have ... = 0
Move the vector you want to the other side and divide by the appropriate constant (assuming its coefficient was nonzero, you can't always do that but here you can)
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Idk where to start
f(-1) = 0
f(0) = 1
f(1) = 2
Yep
Yep
g(1) = 1 + b
g(2) = 2 + b and so on
Yes
the only value of b satisfying this is 2
I don’t understand sorry
wait no isn’t g(1)=2+b?
g(0) = 0 + b
f(0) = 1
no, see g(x) = x + b
at x = 1
g(1) becomes 1 + b
did u understand that?
now look at this one too
the options for b are -1, 0 , 1 and 2
Yes
Right
at b = 1, g(x) is equal to f(x) but we are looking for g(x) greater than f(x)
the only remaining option is 2 whic is correct
So it’s just only a matter of trial and error?
i suppose
or u can see that for b greater or equal to 2 satisfies it
i did so many steps just to make u udnerstand
Right thanks
it just takes like 5 seconds of thinking
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How do you know when to reslove forces and when to use f=ma (eg finding tension or reaction force)
Could you give some context?
show us the context
ok one sec
this is my understanding - you can resolve forces if velocity is constanct (essentially f=m(0) so technically you use the f=ma for both), and use fma if there is acceleration
these questions have acceleration - but most questions state that the body is in equibilrium
In equilibrium we still use fma
We find the forces that go in opposite direction and set them equal to find what we want
they equal = as m(0) as constant velocity so no acceleration
is this correct understanding
You do have acceleration usually
Just that you have the same acceleration up and down
But the fundamental thing you set equal is usually f
yh i mean in some question it will say its in equilbrium (so at rest or constant velocity)
so is it cirrect that techniwualy toy still use fma
like for q lets say there was no acceleration you can still resolve ?
sorry if confusing you hah
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@storm spire Has your question been resolved?
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Actually, you just need to acknowledge that $sin \theta$ = $cos( \pi/2$ - $\theta)$
Sufferrrrring rn D:
yes that is why i converted
.
Sorry, I’m not advance enough for Euler form XD
but it’s alright, at least we are referring to the same concept
De Moivre
Formula
use exponential property for dividing exponentials
and you will be done
numerator becomes e^(4i * theta) as done, denominator becomes (cos(pi/2 - theta) + isin(pi/2 - theta))^5 = e^(i * (pi/2 - theta) * 5)
so yeah
work all looks good, you can just do the division and convert back using euler's formula
so you have e^(4i * theta) / e^(5i(pi/2 - theta))
the denominator can be simplified actually
becomes e^(i * 5pi/2) * e^(i * -5theta)
and e^(i * 5pi/2) = i
so simplifies to e^(4i * theta) / (i * e^(i * -5theta))
= -i * e^(4i * theta + 5i * theta)
now you can just get your answer
and before a helper comes at me for providing sols, she dm'd me and was still confused so i explained it here in the help channel lol
You’re so nice
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If $\frac{z^2}{z-1}$ is always real, then z, can lie on a-
\(a) Real axis
\(b) A parabola
\(c) Imaginary axis
\(D) None of these
Pro_Hecker
I tried using z = x+yi
and got 2x^2y-2xy-x^2y+y^3=0 by imaginary part =0
i don't know what to do next
it doesn't look like that rearranges into any of the first three options, so just (d)
How do you know?
this simplifies to y(x^2 - 2x + y^2) = 0
so... x^2 -2x +y^2 =0
so it this a circle?
the imaginary part is zero when y=0 or when it lies on that circle
i.e. if z is a real number, or if it's on that circle
if y=0 then, can the answer be (a) real axis?
yes
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Pls help
Cross-multiply to eliminate the fractions
then distribute and simplify
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how to integrate this using partial fractions
$\frac{3x+2}{x^2+x+2}$
Pfannkuchen
I know i should split the 3x and the 2 but then idk what to do next cuz i forgot
it is a quadratic that cant be factorized
thats where im stuck
so what you do is 3x+2/(x^2 + x +2) = ax+b
i dont get it
isnt (3x+2)/(x^2+x+2) going to be a fraction
with x in the denominator
1 sec
kk
its fine
wasnt paying much attention, my bad :)
?
i think tht shud work
i think it's supposed to be 3x+2 = A(x^2 + x + 2) + bx + c
?
wait
i got it
thanks fo rthe help
i realized
that the question was asking for if the improper integral diverges or converges and it diverges
so ty
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How do i solve this
i tried to get (a) by using the formula 20-4x/4
but i did not get it
wait is 20-4x/4 == 20/4-4x/4 ??
yes
how is that so?
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[inverse trigonometric functions]
how do you work out the exact values of cos(arcsin(4/5)).
thatw as fast
lol
mhm
what is it?
so x = arcsin(4/5)?
yes
sin(arcsin(4/5))?
4/5
nop
o
im still thinking
sin^2x + cos^2x = 1
i dont think i can work it out
make a right triangle with hypot 5 and a side 4 then ur gonna get the third side by using the pythagoras theorem
ever heard of this
works
yea but I'd only remember if mentioned
is it suppose to be easy or smth and am i just overthinking
Write the equation here
what did u get?
it is pretty simple
cos(3/5)?
now what is x from here?
ye?
huh
u asked cos(arcsin(4/5))
nono this is a dif question
u got that?
ye?
okay
is it wrong
mhm
nop 3/5 is right
assume x = arctan(3/7)
find sinx
sry mb
o
sinx not tanx
7/7.6
no?
As an approximation
actually
ill do the question and u tell me if it's correct or not
arccos[sin(pi/4)]
= 4/2.48?
No
oh fuc btw we got this incorrect cause opp is 3
Notice that sin(pi/4)=cos(pi/4)
how
What is sin(pi/4)?
that's 45 degrees
What is cos(pi/4)
wait
Sin(pi/4) = 1/sqrt(2) = cos(pi/4)
Think about it a bit more
cos = sqrt(16+pi^2)/4
huuh
alr
and not pi/4
how does cos = pi/4
so both adj and opp are equal and make 4
ooo yea mb
allgs
ok actually ima headoff
i gotta sleep early for tmr
yall have been a great help
wish yall a great day
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@supple vector Has your question been resolved?
.close
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quick question
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Why is this false?
suppose x = -1
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are these correct?
A school committee needs 2 more students. How many ways can the committee be selected from a group of 10 students? i say 45 because 10C2
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For the question on top I’m kind of confused because I don’t understand how you get absolute minimum or maximum
i have the critical nimber
The critical numbers are local maxima, minima, or saddle points. The absolute minimum or absolute maximum is simply the smallest or largest value of the function on some domain.
It may be the case that a function does not have an absolute minimum or maximum
yeah but for this i used the cpt theorm which only has one critical number to test
Yes, so you test the critical number. Figure out if it's a maximum or minimum or neither, and then look at the limiting behavior of the function
how do I use a critical number to find the absolute maximum or minimum because I’ve searched up two different ways, and one is through the second derivative test or finding the limits but i want to know the most efficient way
If, for instance, the critical value is a minimum, but the limiting behavior as x->0 is to diverge to negative infinity, then your minimum cannot be an absolute minimum, for instance
@toxic haven the second derivative test is only to determine if a point is a minimum or maximum
this seems more straightforward
So the second derivative test can be inconclusive
how
Consider y = x^4
And y = x^3
We know that y = x^4 has a minimum at x = 0, but y = x^3 does not
What does the second derivative test say for these functions?
to use the first decorative test
derisive
but ur right it’s better to use linits
in this case how would i?
i don’t understand what function we’re talking about whenever we say as d approaches to infinity or zero
x*
So the stuff with limits is to determine if there is an absolute minimum or maximum at the endpoints of the function, (if the domain is finite) or if the function attains a larger (or smaller) value that any of our maximums (or minimums) found by the critical point tests
You need to do both
Additionally, you need to look at discontinuities in the function, if any
And the limiting behavior approaching those
Using limits on an open set to determine extrema and ignoring the difference between maxima/minima and suprema/infima in their screenshot makes me want to roll my eyes
the screenshot i sent did it wrong kinda?
It doesn't really matter at this stage, it just makes me judge the lecturer
First, I find and classify all of the critical points, and find their values. Keep the largest local maximum and smallest local minimum. Note that any discontinuities in the function will be captured in the critical points, but sometimes the definition of the function can make you miss removable discontinuities, so
Next, I make extra careful I got all of the discontinuities, and took care of weird cases not covered by things like the second derivative test, for instance, locally infinite slopes for finite functions, cusps, and so on, I categorize these as well.
Third, I look at the end points of the domain, are these open or closed? What values are these approaching?
Finally, I've gathered all of the information I need to figure out which point is the absolute maximum or minimum. I just find the point which is the largest or smallest. Sometimes though, this is not possible, and the function doesn't have an absolute maximum or minimum.
i’m still reading it 😭
Feel free to freeboot it.
okay i got it
so how would u approach that with the question i have cause we are usuing critical point theorem
Well, I told you how I would approach the problem, so how about this, using the above approach, give it a shot, and if you get stuck, I can try to help you
You find the value of the function at that point, and also the value of the second derivative
what would i do now
Ok, so the second derivative is negative
yeah
This implies that the critical point is what, a local max or a min?
It's not a min, so it clearly must be a max, so maybe it will be helpful to reason through why it's a max
Why do you think this is a max?
vause its concave down
Right, but more specifically, the second derivative measures concavity of the original function
But what does it measure with respect to the first derivative?
So the second derivative is the derivative of the first derivative
Seems silly to say it out loud
But this means everything that you know to be true about the derivative is true about the second derivative as it applies to the first derivative.
yeah
So at the critical point we know that the derivative of the function is 0
And so we know that if we consider the derivative as a function in its own right, it either goes from negative to positive or positive to negative, or it bounces off in some way.
If the second derivative is negative, this means the derivative is trending down at the 0.
yeah
Going from positive to negative.
yeah
So if we know the derivative is going from positive to negative, what can we say about the original function?
Well, if a function's slope is positive then it's increasing
And if a function's slope is negative then it's decreasing
yeah
So what happens if you have a function whose slope changes from positive to negative?
decreasing
So imagine the function is like a ball traveling through the air
It goes up then it comes down
Did it reach a maximum or minimum height?
it hit a max height
Exactly
so it would be absolute max?
It is a local max right now
So that's paragraph 1
We've handled all of the critical points, are there any discontinuities or anything like that?
no
Ok, now, what is the behavior at the edges of the domain?
First, what is the domain?
Cool, and what's the limiting behavior?
when x approaches infinity it iincreases?
Can you show your work?
for this is where i’ve been getting stuck
because i did do a whole chapter on limits
i just don’t know how to do it for this mean i don’t really know what it means
like when u say x do u mean like plugging in smaller numbers to see if it increases or decreases as it reaches 0?
Ok, no worries, so in this case for the limit to infinity we can do a power comparison test
okie
ln(x), because it is logarithmic, has a smaller effective exponent than any positive n, x^n
On the other hand, the x^14 is just 14
So which term grows faster?
no idea 😭
it gets smaller
Yup
Let's say I make b massive, it's a million times bigger than a, how big is a/b?
very small?
Sure, but if it's exactly 1,000,000 times bigger than we know the value a/b
a/(1,000,000 a) = 1/1,000,000
So it becomes one millionth
yeah
So we can make b as big as we want, is there any limit to how small we can make a/b?
it can’t be 0?
okok
If you give me a super small number, which we call ε, I can find some value of b which makes a/b smaller than ε
yeah
But the rule is ε must be > 0
So as a result the limit as x->inf is 0
Because x^14 grows much faster than ln(x)
So we can always find some x big enough to make the value smaller than whatever ε > 0 we choose
what would it be for 0?
Well, we can do a different dominated convergence test, this time for x->0 we have that ln(x) -> -Infinity faster than any x^n for finite n.
Or you can use L'hopitals rule
Actually, you could have used L'hopitals for the last one too
Calculus
like more specifically
Or perhaps "Analysis" if you're seeking a math degree
how would i practice this
Well, what textbook are you using?
Stewart?
If so, one of the major strengths of Stewart is the sheer volume of excellent and interesting problems.
Just assign yourself homework from the chapter on limits
okie
okay again
why do we test the limit of inf of ln x and not x^14
but test the limit of x^14 for 0
We do both
It's just that x^14 dominated as x -> inf, but ln(x) dominates as x->0
Well, technically we have infinity/0 which isn't even really a question of where that's going
The numerator says infinity, the denominator says also infinity.
ik i was still abit confused on that
when we say x approaching 0 or inf we mean the x in the orginal function right?
Or just the x in the numerator or denominator, depending on context.
what about this context
Well when we're considering x^14 and ln(x) separately, then the context is whichever one we're talking about.
But when we put it all together, it's all together again and the context is the entire function
can we consider it all together?
Sure
Just seeing where it is going
Ah yes, sorry
You mentioned this a while back, but I didn't recognize the name
Yes, you can just use that
And make your life easier.
😭😭😭
i’m just confused because
they say if u find relative max it’s also the absolute max?
I'm trying to do a super general step by step process for the possibility of a really misbehaving function.
Whereas you have a rule for a really nice function
Which I was unaware you could use
And that makes this problem super easy
Only if you have a continuous function with a single critical point on the interval
because we did the second derivative test and we got that the function is a relative maximum so that also means that the thing is also absolute maximum?
And that critical point is a local max or min
yeah we have that
Yes exactly
We do, but I wanted to emphasize this because you don't always have this
You do need to check the conditions in order to use this fact
okay so we got that figured it out
Yup
🥳
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why is this not a subspace?
Well, do you think it should be?
If so, try verifying the conditions for a subspace
so would i use the form p = ax^3+bx^2+cx+d
what's $\P$? The field of polynomials ?
You could
ƒ(Why am. I here)=I don't know
ye degree less than or equal to 3
could someone explain what happened here?
!occupied
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AB = CD
AD = BC
It is indeed slanted
Look at part B and it's distance to bottom, it's 5
From C to bottom is 1.5
It is slanted
Ah
I thought AD is also slanted
But yeah you're right ig it's not slanted
I would say it is not slanted, but if you have the opportunity to ask your teacher, then sure why not
Okay yea ask your teacher
Because if AD is slanted, then question is much easier solveable than when it's not
You can send it here and if I can't, someone else might
What do we know about the circular part
Alright
How do you think we can approach this problem?
It's fine
What is your initial idea
Imagine you know the curved part
Let's call it X (Imagine we know it)
How do you find the answer?
Hmm
Let's look at it in another way
If it was normal triangle, without the curved part, it would've been easier to solve this, do you agree?
So let's do something
Let's solve the question not considering the curved part
And then deduct the curved part from it
yes yes
I tried to replicate the question
Let's find the purple part, then deduct the blue part
Excuse my drawing skills
Yea but we'll get to that
So big triangle is 20
Now as for the blue part
It seems like the curve, is part of a circle
In other words like it is a quarter of a circle
Yes
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The mistake is from lines 3 to 4, you can't combine exponents like that
$a^b * c^d \neq (ab)^{c+d}$
thewizardofOU
how could I resolve it?
okay so
key line you messed up
was after
$f'(x) = 4x\sqrt{2-x} + 2x^2 \left( \frac{1}{2} \cdot (2-x)^{-\frac{1}{2}} \cdot (-1) \right)$
poudel
instead of turning 1/2 into 2^(-1), try multiplying all the numbers together as is
i.e. try simplifying by doing 2 x 1/2 x (-1) instead
Np
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a,b,x,y are real numbers such that
$$ax+by=3$$
$$ax^2+by^2=7$$
$$ax^3+by^3=16$$
$$ax^4+by^4=42$$
find $ax^5+by^5$
Skill_Issue
that's wrong I think
idk i was think we take x and y common or somthin
,w (ax+by)^5
hecker
I saw a solution to this on youtube
the trick is something like
(ax+by)(x+y)=ax^2+by^2+axy+bxy
3(x+y)=7+xy(a+b)
and forming another such equation
$ax+by=3$\$\left(ax+by\right)\left(x+y\right)=3\left(x+y\right)$\$ax^{2}+by^{2}+xy\left(a+b\right)=3\left(x+y\right)$\$7+xy\left(a+b\right)=3\left(x+y\right)$\\$ax^{2}+by^{2}=7$\$\left(ax^{2}+by^{2}\right)\left(x+y\right)=7\left(x+y\right)$\$16+xy\left(ax+by\right)=7\left(x+y\right)$\$16+xy\left(3\right)=7\left(x+y\right)$
B-eard
do similar with ax^3+by^3 and you'll have two linear equations in xy and (x+y)
@tall moon Has your question been resolved?
$$ax^3+bx^3=16$$
$$(ax^3+bx^3)(x+y)=16(x+y)$$
$$42+xy(ax^2+by^2)=16(x+y)$$
$$42+xy(7)=16(x+y)$$
what do i do now
Skill_Issue
ok, i got xy=-38 and x+y=-14
@tall moon Has your question been resolved?
2 answers for xy given these 2
y=-38/x
y=-14-x
-14-x=-38/x
14x+x^2=38
x^2+14x-38=0
(x+7)^2-88=0
use quadratic fomrula
wait a minure
$$ax^4+bx^4=42$$
$$(ax^4+bx^4)(x+y)=42(x+y)$$
$$ax^5+by^5+xy(ax^3+by^3)=42(x+y)$$
$$ax^5+by^5-38(16)=42(-14)$$
Skill_Issue
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well, what have you tried
Options are
a)All necessarily real
b)non real except one psitive root
c)non real except 3 positive roots
d)non real for three positive roots of which exactly one is positive
do you need the exact roots
or number of roots
okay
find the points of inflection
Hey
hello!
yes
It must cut the x axis at one single point
Can we use wolfram to plot the graph ?
dang
nope
Coz i am not that sure tbh
i believe it is
it is definitely right though that's just the solution
is there any other alternative method ?
I dont think so
yeah foil it out
okay
lol dont
exponent of 2009 dominates the others
wolfram alpha can't compute lmao
yes
,w (x-41)^49+(x-49)^41+(x-2009)^2009=0
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rip
,w zeroes of (x-41)^(49)+(x-49)^(41)+(x-2009)^(2009)=0
,w (x-41)^49+(x-49)^41+(x-2009)^2009
woah
,w (x-41)^49+(x-49)^41+(x-2009)^2009=0
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lmao, just expression
Can we do it by numerical method?
how did you calculate?
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If its given that Det(A)=0, can we say anything about Det(Adj(A)) ?
Det(adj A) = det(a)²
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✅
For 3*3 matrix
For n th order matrix
Det adj (A) = det (a)^(n-1) generalised
@remote mural Note this bro
i was talking about a 3*3 matrix anyways
thats what we get for almost all the questions
I forgot this property
Ah !
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could someone explain this proof pleas
*please
you need to say which steps you dont understand
step k
what do you not understand about it
this isnt the first time we've had this discussion. you need to be clearer about what you dont understand
like what's happening in step k
look I dont know how to answer that. axler wrote quite precisely what is happening. you need to say which of what he wrote you dont get
I can repeat the same thing but that wont help
ok, let me put it this way. I don't get what he's doing
so we first construt a subspace with the elmennt {0}
then {0,v_1}
(0,v_1,v_2,v_3..}
and so on?
no
at the start, we have two cases, either U = {0} or not
in the first case we are just done
the space {0} is finite dim
yes
otherwise, we start by picking some vector u_1
now, we could either have U=span(u_1) or not
in the first case we are done
otherwise, we are picking some u_2 which is in U but not in span(u_1)
and again we have two cases, either U=span(u_1,u_2) or not
in the first case we are done
got it
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this is the set

