#help-10
1 messages · Page 366 of 1
Ouais ça marche
Par contre la traduction est limite
Les matrices de permutation c'est un autre concept qui existe aussi
On dit plutot "change of basis matrix"
Changement de base quoi
Je suis actuellement dans les matrices de passage ahah..
Les matrices de permutations me disent de quoi, mais je ne me souviens plus ahah.
Enfin bon les matrices de permutation c'est un cas particulier de matrices de passage en vrai, donc c'est pas faux ce que tu dis, c'est juste trop spécifique
Mais si vous me dites que mon raisonnement fait du sens, J'ai totalement compris les changement de base alors. ça sert à "comparer" deux vecteurs de bases différentes en convertissant l'un vers l'autre base.
Oui exactement
Ok good j'ai totalement compris.
Et ça a donne que la matrice de passage revient à faire un produit matriciel de deux matrices.
Ok good, c'est résolu, merci.
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How to find area of these shapes?
You can view this as multiple triangles
Do you have the length of a side?
For example, you have 4m for the hexagon.
You could use some pythagore or sin/cos/tan to find the whole length oh the haxagon, then divide it in two to find the distance to the center... if you have learned about these.
Could you do the hexagon one I understand the other two
Sure, hold on.
Sinc ethis is a perfect hexagon, the red triangle should be isocele, thus have 2 equal side.
Does that make sense?
The current issue is finding precisely this length to the center.
So my approach was to find the whole length from one side to the other. as such in blue
Isn't this also possible
Then, once you have this whole blue line
You can cut it in two
and get the triangle.
This is quite complicated Isn't making 5 triangles easier
Let's try your approach
What would be the distance of the orange line?
How would you find it?
Keep that close please to undertand later.
That's my question that's what I'm confused about I would find the green and do sin of 30 but I can't find it for some reason
Now that I think about it, it would be possible somewhat.
First we need to know what are the angles of the triangle.
120 degree yea
360 / 8
Then divided by two, to get the angle between orange and green
And you would be able to use tan to get the orange line.
Wow I did not think of doing it this way 😄
The blue is 360 degrees
You have 8 triangles. Thus we divided in 8.
Then we divide in two because we want the angle of one of the two triangles we made.
So could you find it for me please and show calculations so I can understand
Yes.
Thanks
adjacent would be the height you would use to find the area of the triangle.
IE the orange line.
OK thanks
Does that makes sense? It is an interesting problem.
But is this not possible with sin
With sin, you would find the green line
As with sin, it would be opposite / hypothenuse
Ok is this the easiest way? Because I have a test soon
It looks much easier than my approach earlier.
And would apply to any size of polygon basically
you could try with a square just to be sure.
Remember that once you get the area of the triangle, you will need to multiply it.
And the vertex is 45 each base would be 67.5 eliminating use for tan
@safe stirrup is it possible?
Where does 67.5 comes from
Each base because the triangle is 180 and vertex is 45 so 180-45/2
Octagon
to use sin instead.
Good point.
As long as you respect the sum being 180, and the correct division (SOHCASTOA), you will be fine.
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so far im at $$ \frac{2\sin t}{1-4\cos t} $$ but idk what to sub in for t
morphine_addiction
@errant crane Has your question been resolved?
well you know what the y-coordinate is
(and the x but it will be easier using y)
can you find t from there
(assumedly you need both to narrow down t, hence them giving it)
yes, i didn't think of that
so $\arccos{\frac{1-1}{2}}$?
morphine_addiction
yes
so i did $\frac{2\sin(\frac{\pi}{2})}{1-4\cos(\frac{\pi}{2})}$ which got me 2 but the answer is -2
morphine_addiction
i dont understand that
so if you find 1-2cos(pi/2), is that the same as 4-pi/2
nope sorry
pi/2 - 4 sin pi/2
is that the same as 4 - pi/2
4-pi/2 is negative
so they're not the same
what does that tell about the value of t you got
because if it's the right one they should be
but what did i do wrong?
what's cos(-pi/2)
0
the same as cos(pi/2)
so you have to remember that there are multiple values of t such that cos t = 0
ye cos its symmetrical
you have to use the x-coordinate to find which is the right one
how would i know pi/2 is wrong tho bc its still in the range
either you look at the graph and realise the gradient should be negative (you got positive) and go and try another value of t
or you check to see if pi/2 gives you the right x-coordinate (it doesn't)
that's what this was about
alight, so bacically try a bunch of things until it looks right
practice should help
it will
and remember whenever you take an inverse trig, remember that there are multiple values
(which may need to be negative)
i didnt know that, i know when u divide by a cos/tan/sin 0 is a solution but didnt know the inverse thing
thanks for the help
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say I have a point A in 3d space, and I want to rotate it around the origin by $\theta ,\varphi$. How would I do that?\
I dont know too much about trig btw, go easy on me
DerTheo
you find A in spherical coordinates, add those angles, and convert back if you want
is there an easier solution though?
uh there are rotation matrices that do it for you
technically you have to say if you want to rotate by theta first or phi first
rotation matrix is just a big formula that you multiply by your point to get the new point
ok
this thing apparently
so cartesian(rotate(spherical(A))) basically
yeah Ive seen that
yea if you convert to spherical it's just adding numbers
if you want to go cartesian to cartesian you use the matrix
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how can i find series representation of this around zero?
i know that d/dx(1/(1-x))=1/(1-x)^2
and that
but what should i do now
should i just derive that series?
yea
so ill get $\sum_{n=0}^\infty nx^{n-1}$?
Slowaq
Slowaq
why?
That’s the same thing
Because the first term of this is 0
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I am completely stuck
what have you triederino?
I dont know where to begin
Maybe you could notice that the integral of a sum is a sum of integrals
i noticed that
and you probably know how to integrate a constant function
you can also pull out scalars
but do i try and get the basic f(x) and g(x) functions like solve what they are
ohh then it would be the integral equal -12
i just dont know how to stary evaluating the other problems
It's a good exercise and I don't want to spoil every detail of the solution so you should probably give it a few minutes and think about it on your own
if i know from (-2,4) f(x)=-12 how would i love the one where it is from (4,-2) (f(x)-3)dx
i know i can start by flipping so its (-2,4) -(f(x)-3)dx
One additional hint I'll give is that exchanging the bounds of integration amounts to multiplying the value of the integral by -1
i see that
yeah exactly
I think you have what it takes to solve the full problem
do i substitute the f(x) for -12
I am stuck
especially for the next equations where its a different integral and i have to find it
do you have anymore tips
Begin by writing each of the integrals as a sum of two integrals
(except the first and the third one)
If you integrate a constant function then just compute the integral
and recall this trick
wait do you mean do that for the fist given equation or the first equation i am solving?
I get 30 for the first one
For the first given equation
and in general for the integrals you're given
im not getting that answer
is there any visual examples you could send
Maybe I made a mistake. Maybe if you solve the second one then we can see if we agree on the second one
or maybe you can show your working and I can try to see if it makes sense
are you able to see the image?
Your top right integral should have an additional minus sign
because you exchanged the bounds of integration
Then you'll get the same result as me
Well done
ohhhhhh okay thank you
would g(x)dx from the interval of (-2,4) be 9.2
for the second one i got the answer 21.2
I get 4.2
wouldnt it be 3+1.2+5
Why +5?
3+1.2 takes care of first integrating from -2 to 0 and then integrating from 0 to 4
no worries ^^
so for my overall answer i got 16.2
That makes sense to me. Well done!
Thank you so much, I can do the rest on my own now
great ^^
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anyone know computer science stuff/

How do I determine the order of this tree?
@ripe merlin Has your question been resolved?
help
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Can someone explain 9
I don’t understand why the 1st degree polynomial is negative
When the derivative at that point is positive
Find the third degree Taylor polynomial
for??
Question 9
no what formula
At 0.5
what equation do they give u
are u sure this is the answer key no?
But like can u ss the question, there is lack of context here
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How to do this I have no clue
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What’s wrong
looks like you need to simplify and rewrite what you got for d y/dx
factor out a -3 from both the numerator and the denominator
in the last bit you simplified wrong
you multiply y to the top and the bottom of the complex fraction
but you forgot to multiply that y to every term in the numerator
Where
The x times x/y?
x^2/y part
I thought when it’s like that it just means it’s on the denominator/moves there
that only applies if all of the terms in the numerator are divided by y
so the equation of a tangent line requires two things
the slope and the point
we can find the slope using the derivative
and we're given the point
2x+2yy’=0?
So am I suppose to just plug those numbers in
yeah
and you need to find dy/dx
so like it might be better to solve for that first
and the plug in the numbers
Dydx=-2x/2y
yep
How
Oh y-4=-3/4(x-3)?
yep thats it
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Did I do his wrong
This
But still got the mark
Cuz theta should be (2 root 5)/5
It's just asking for the triangle
and gives coords btw
if you cant read french
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@warped zinc Has your question been resolved?
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anyone know how to go abt doing this
all i know abt p value is that it is the lowest value at which we reject the null hypothesis
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anyone have idea on Lebnitz's rule on Definite Integration?
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can someone explain me why option 4 is correct
also I am wondering what the LUB if 4 and 6 is? Its not valid right?
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im on part b but im having trouble with finding the horizontal distance. I know that initial horizontal = final horizontal velocity and im supposed to be using these 3 equations:
the problem im having is that i have u_y, u_x, but i dont have v_y or t so i dont think i can find s. at first i assumed that v_y = u_y since i think its implied it lands at the same height it is launched from so i tried to find t from there but i just get t=0 or s=0 which doesnt help
get your own channel
oh mb
there ya go
thanks
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parallel means same gradient
gradient being the slope
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find radius of the circle
What did u try?
i found the sides
and then phythagorus? for half of the triangle?
but now what
the side of the square inside is 10
but in what way do you split it in terms of r
the 8-r and 6-r on hypotenuse can be found using congruence
so 8-r+6-r=10
14-2r = 10
r=2
can u pls explain how
i cant recall it
see the radius is equal
yes
and the hypotenuse is common
and the angle between them is 90 degrees or Pi/2 radians
so by pythagoras theorem, the part of hypotenuse should be equal in both smaller parts of triangles
alternatively, by rhs congruence the parts of hypotenuse must be equal
huh
btw there is a formula to find radius of inscribed circle for right angled triangle , i think its
r = (P + B - H)/2
P being perpendicular
B being base
H being hypothenuse
r being radius
is there any info about if the triangle is right angle?
yeah that gets the correct answer
but i need to do it from scratch
yes, its right triangle
what u mean , like prove the formula and then get the answer?
no
this way
how do you split the hypotenuse in 8-r and 6-r
i dont get that
oh ok
orange dots represent the 2 triangles being congruent
yellow dots represent the 2 triangles being congruent
so 8-r = base of 1 triangle = base of 2nd triangle = 8-r
but how are the triangles congruent
the angle is common and perpendicular is common
but that isnt RHS congruency
see, the marked angles are perpendicular by construction
OH BRUH
im stupid
i was trying congruency for these 2 for some reason
thanks
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find missing term
4 7 7 3
6 1 5 x
5 x 6 1
7 3 4 7
not really math but yes
No rules?
options are 2, 9 and 5 if that helps
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Sum of every row is 21 if x = 9 atleast
hmm
I feel like the question is missing or something. Do you know the specific subject?
this makes sense tho
Then it sounds like it should just be 9
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is there some mysterious cancelling here because shouldnt it be a division by 0 error?
Why would there be that?
because like 1/(x-1)^3 right
?
1/0
or does it not matter because its in sin function
Thats also only for x!=1
uhh i am confused
for part b it says f'(1)
i mean from the calc
it says f' is that
Yeah thats the problem
why is it 2
like i subbed in n=2 and n=3 here
either way i think am goin to get a division by 0 error for f'(1)
No you are not
please explain i dont understand 😭
For a derivative to exist at a point the left and rhs limits needs to be equal
(And continious)
So for example for n=0 find derivative for x!=1
Take limit from the left and the right
Check if they are equal
is this what u meant by taking limits from RHS and LHS?
also this is not continuous because x = 1 breaks it right?
Wdym?
No meant doing it formally. How do you know your function doesn’t behave differently at 1.0000000000000000000000000001
Or working with limit properties
i meant like for a function to be continuous at x=a, then the point at x=a must exist right?
but like subbing in x=1 makes it so that it doesnt exist
in this one
Again that is not how the function is defined at x=1
oh...
(And doesn’t make any sense to speak of continuity at points where the function isn’t defined)
Yes
But I would suggest you find (much) simpler examples before doing that exercise. Because you seem kind of lost
$$f(x)=\begin{cases} x^n\cdot \frac{1}{x} & x\neq 0 \
1 & x=0 \end{cases} $$
ScapeProf
Find smallest non-negative n such that f is differentiable at x=0
hmmm
Start with n=0
A necessary condition for differentiability at a point is continuity
So start with checking if continious
errr
whats the formal way to do that
because like i'd just sub in like
some small numbers to the left and and right of 0
but.... that clearly isnt it
lim x->0+ of 1/x sort of standard, but if you don’t know that you have to use definition to show limit is inf.
But idea is you prove a few formally then use properties of limit once you know a few limits to show everything else
hmmmmm
alright
ill look at some more basic examples online and learn this
thanks :)))))))))))))))
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why did denominator go from 4x to 8x
also where did the 2 go from denominator
u cant multiply that with 4x+2 cuz 4x+2 has a power of 1/2
Oh yeah
What can I do though
The numerator is wrong too apparently
Answer sheet says this
what's 4/2
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how to solve this
plug in each value within the domain
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just need to verify if this is the ideal/intended/best way to solve this (i.e., change of base, cross multiply, square root etc so on and so forth)
seems fine to me, you could simplify the change of base as 1/log_y (x^2) = log_(x^2) y instead of writing 4 separate logs but it doesn't make much of a difference
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Is it possible to write U in terms of x1,x2,y1 and y2s only?
;l
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W = (1-iz)/(1+z) , z is a complex number, then w is real/imaginary/not defined?
Multiply numerator and denominator by $\overline{1+z}$
SWR
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Hey, I've been trying the understand the proof behind undermined coeffecients of linear differential equations with constant coefficients
so generally something of the form $Ly = f$ where $L = p(D) = \sum_{i=0}^{n} a_iD^{n-1}$
So the proof says that we can consider $f(x)$ a solution to a homogenous LDE with constant coefficients
so $f$ would be the general solution to $\tilde{L}y = 0$
considering L and $\tilde{L}$ are both linear operators
We can just take $\tilde{L}(Ly) = \tilde{L}(f) = 0$
let's say $\tilde{L}L = \hat{L}$ we know that the general solution to this, will be f(x) and any solution to $Ly = f$ and any of their linear combinations
So $\hat{L} = \sum_{i = 0}^{n}c_iy_i(x)+ \sum_{i=0}^{n}d_iu_i(x)$
so we can deduct that $y_p = \sum_{i=0}^{n}d_iu_i(x)$
this is the part I don't get:
in which case there are two options either there exists a $u_i(x)$ that has the same root as one of the $y_i(x)$
which means we can see that there exists a solution of the form $b_0x^ry_1(x)$ whith r being the multiplicity of the root of $y_i(x)$ + the multiplicity of the same root of $u_i(x)$ minus 1
or it doesn't in which case $b_0x^ry_1(x)$ r is equal to the mulplicity of the root of $u_i(x)$ - 1
Mephisto
why is that that if there are any roots found that match that this is the case?
and can I assume that any solution to using undetermined coeffecients is of the form $P(x)e^{\alpha x}cos(\beta x) + Q(x)e^{\alpha x}sin(\beta x)$ where P(x) and Q(x) are polynomials
Mephisto
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hi
I have sent a suggested solution as well as my work
the thing is we got different Constant
but all the steps seem logically correct
what's wrong
@strong aspen Has your question been resolved?
when distibuting the 3/4
I think it essentially gets absorbed into the C
so you can technically multiply this C by 3/4 to get rid of it, at leat that's how your solution sheet did it
btw that's x^1/3
they absorb everything into the C
yeah I got that
but is it technically still correct my solution or teachers solution is correct
ln(x) = 0 if x=1 so left term at the end would cancel out and give C^3
but logically my solution for question A is right but it doesn't do sm like this?
anyways feel free to try the question for yourself w/o looking at the answer to learn
hold on I'm looking into it
My assumption would be, you have to absorb everything you can, before you can plug in numbers
I think that's the issue, but if I were you I'd wait for someone who knows more about it then me
<@&286206848099549185>
I'll just ask my teacher tomorrow, or if anyone is down to answer please do it in my dms 🙏
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can someone explain why the summation becomes this, its been a long time since i've dealth with summations
in the previous step it was this
i understand changing the index and bringing the second p outside since its a constant not too sure about the rest
after looking into sums of infinite geometric series i understand why we get the denominator but i dont understand the numerator
<@&286206848099549185> any ideas?
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Stuck on question 3G and 3h
!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
1
these are soled the same way as you presuambly did during question 2
get rid of the brackets, and then rearrange to solve for x
I never done 2
the same way you did any other question in 3
So I simplify it
Yes
expand each bracket individually
do one side at a time: first, what is 4(2x-3)
sorry that's f)
So it will be
What question is that
3g)
try and use the asterisck * to mean multiply on here as it gets a little confusing otherwise
2(1-x)
can you get rid of the brackets and simplify here
Okay
Okay
2*1-x
X doesn't have a value
Well it does but not in this
I need to remove the brackets
and then find the value for x
right now im only asking you to expand out 2(1-x) in isolation
ignore the left hand side of the equation; what is the expanded form of 2(1-x)
so it become 2*1-x
it becomes 2 - 2x
how
2(1-x) you can think of as 2 multiplied by 1, + 2 multipled by -x
If 2*1= 2 then it will be 2-x
the brackets are important
2 is not only multiplied by 1, but also the -x
there is a difference in saying 2(1-x) and 2*1 - x
2(1-x) = 2*1 + 2*-x
this is the same for any bracket with a number multiplying it: they times each number individually, not just the first one
Ahhhh
is it because of it like this
2*3+x
but done in the same way just shown differently
be careful with your notation with brackets especially now that you know they are different
i am unsure if you mean 2*(3+x) or 2*3 + x
I am just stressed because i have a junior mathematical challenge
It's confusing me
do not worry, once you have this concept down you will find these questions fine
that's just helped me now
would you still like help with g) or would you like to go over the other questions in 3)
I will like to go over the other question in 3 then work my way up
May i be excused for a moment
sure, @ me when you're back
Okay
Actually can I do it tomorrow as I will be more energised
Yes because the second a cancels out
sure, have a read of https://www.mathsisfun.com/algebra/expanding.html if you need a resource in your own time
Expanding means removing the ( ) but we have to do it the right way!
Thanks
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hello
"find the sum of the given series, or show that
the series diverges (possibly to infinity or negative infinity)"
im not sure how to approach this problem
any tips?
you can use comparison test
what is that about?
finding a smaller series that still diverges
we find a smaller series by making the denominator bigger
any ideas?
1/2a
but why does that work?
i think im suppose to use one of these
or this
I dont think they help
yes
but how does that help me
if you were to make the partial sums of a diverging series bigger then it diverges still
like it makes it worse
i thought you used it previously somewhere else
oh
what are the options you have other than these 3 theorems above
next chapter is about comparison test
anyways
i dont think i understand partial sums
if i have a series
partial sums is the sum of the first n terms ?
and this thing here confuses me
well the word suggests it already
say you have a sum n = 0 to infinity with a_n
a_1 is a partial sum
a_1 + a_2
a_1 + a_2 + a_3
a_2 + a_3 is
a_2 + a_3 is not a partial sum?
You can define $\sum_{i = 1}^{\infty} a_i$ as $S_n = \sum_{i = 1}^{n} a_i$
Then if the sequence $\lim_{n \to \infty} S_n$ converges then so does the series
𝔸dωn𝓲²s
it's basically
the ver same thing
to solve
this
yea
then show
$\lim_{n \to \infty} S_n = \lim_{n \to \infty} \sum_{k=1}^n \frac{1}{2k-1}$
but wdym with sequence?
𝔸dωn𝓲²s
a sequence is not a sum...
lets say
1 + 2 + 3 + 4 + 5 ...
so you mean
the sequance if this partial sums is:
{1, 3, 6, 10, 15 ...} ?
yea
alright well so in order for me to see if the the sequance if this partial sums converges, i must find a formula for {1, 3, 6, 10, 15 ...} right?
𝔸dωn𝓲²s
yea
but to find that is pretty difficult
for any series
well you would have to go till infinity
comparason test
if the partial sums are finite then it always converges
because it stops at some point summing up
but with infinity it doesn't
and finding a closed form is pretty difficult
series is not a sequence, but you can rewrite it as one
.
S_1 tells you the partial sum at n=1
S_2 at n=2
...
S_k at n=k
and that resembles a sequence
if you were to do it infinite times (basically take the limit to n->oo) and if that converges then the series converges
it's a basic and important thing
but doesnt really help to solve these
yeah... i guess i will just move on to the next chapter and learn comparason test
i have exam in calculus in 3 days
so much more to learn...
but i will try my best, thanks for the help! 😄
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wut
you mean (-2)^3?
yes why is that in brackets
cause -2^3 and (-2)^3 are different things
say x=-2
so sqrt(x^2) = sqrt((x)^2)=sqrt((-2)^2)
its just to distinguish that the whole -2 is taken to third power
not just the 2
for third power it doesnt change much
but for even powers would
i know that but it didnt ask rewrite the number (-2) it said reqrite the number -2
its actually kinda confusing to explain just think about it this way If u do -2^2 it will be -4 while if u do (-2)^2 its 4
yes i understand that
100%
but right here there is no brackets
so why do we change it
thats just cause if its put by its self its fine you dont have to put brakets
from this context its obvious you take (-2)^3
if they asked for -(2^3) it would be clear they ask for that
ok
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is a repeating decimal rational?
like is 33.33333333333333333333333333 rational since it repeats?
Yes
A decimal number is rational if and only if it repeats
They are the same thing
but like 34.35 is rational righ
but 36.3234242348320407395873204983725098790932578329085473209573259032879450 (image it keeps going)
is irrational right
Yes, but it can be written as 34.350000000... which repeats
Correct
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i think 3 and 5 are wrong
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my calc gives an error when getting the root of a negitive number
will the number allways result in a negitive
(like can i just do it without negitive then add back the negitive no matter what the ro ot is 4th root 5th root etc
error for the cube root?
huh that's pretty weird
you can just ignore the negative and add it in the end yea
an odd root of negative is negative
did you actually use a cube root on your calc ?
you only said "root"
But if the root is positive
How do I know
Yes just said root since other questions have different roots
odd root of a positive is positive
even root of a positive is both negative and positive because reasons
Positive root of a negative number isn't possible right
even root of a negative is nothing yea
since when you multiply negative numbers it goes back and forth + and -
The root of a positive is always positive right
But it's not possible to find right
yea you can't find the 4th root of -100 or whatever
So positive root of positive is positive
Odd root of positive is positive
Odd root of negative is negative
Positive root of negative isn't possible
👍
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I have a math project where we are making new casino games and playing them in class. One of the tasks is to determine the probability of each possible outcome within the game. Currently my game is where a deck of 18 cards (all but Aces, Kings, Queens, Jacks, and Jokers are removed) are laid down on a table (face down of course) and the player has to choose 4 of the cards. Prior to selecting the cards the player bets on what outcome is going to happen (ex. 3 Aces are chosen) and depending on how rare the outcome determines the pay out for winning. Additionally if they get a joker it trumps the payout upon being drawn, red joker meaning they automatically win an amount determined by spinning a wheel and a black means they lose. I am having trouble though for one of my outcomes: the probability that a pair of any kind is present in the 4 cards drawn. Currently I am getting a ~103% chance of it happening ((16C1 * 3C1 * 12C2) / (18C4) = 1.03...). I understand that the probability of it happening is very high and that I should not add the ability to bet on it in the game but it is making me question all my other calculations for the other outcomes. I am feeling quite stupid right now as this feels like a very simple oversight and any help will be much appreciated. Thanks in advance.
For the pair of any kind does it include pair of jokers
No...
The idea was that there are only 3 cards that can create the pair with the first card selected and only choosing one of them to create a pair
Ah I see...but any card can be a pair hence the 16c1 then the 3c1 because with 4c2 I thought that it would mean you need to decide which card you need the pair to be
It’s been a while since I did probability but
I remember my teacher saying to start off with the most specific
So that’s why I started with 4c2
Idk I might be tripping
Let’s see what others say
Yeah I typically do it that way too but I didn't see how that would work here considering whatever the first card drawn is determines what the second card must be (not literally first and second card but hopefully you get what I mean)
Actually mine is wrong it needs to start with 4c1 and then 4c2 p sure
4c1 determining which card value (Jack, Queen, King, or Ace)?
Lol I got ya
Ugh now I’m thinking 4c1 x 4c2 x 3c1 x 4c1 x 2c1 x 4c2
Huh lemme check...I know I can get the answer by figuring out the probability of not getting a pair (1-(4c1 * 4c1 * 4c1 * 4c1) / 18c4)
Unless that is wrong as well
HUh yours got me 113% so something isn't quite right...
This gave me ~92%
Of getting a pair
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Was sent this proof by my teacher, but it is wrong. Any ideas on the actual inductive process to take? The idea is to prove that the degeneracy for the nth level is 2n^2
what's the full question? n^2+n+1 isn't (n+1)^2
exactly my issue
lemme translate the question real quick
it's in spanish
To find the possible states for a certain n ∈ N, we proceed as follows
nevermind
probably the mistake is that it should be 2(2n+1)
he missed a two
if someone else notices something else lmk
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well there are 12 ways to arrange 12 tasks
and each group of 2 tasks can be arranged 2! ways or 2P2 ways
and there are 6 groups
and since it doesnt specify the order of the groups, we can assume it doesnt matter and say its 6!
so couldn't u just do (12!/(2!^6) * 6!)6!?
i wasnt finished
that sounds too big still
it's significantly bigger than the answer to the first question
and the answer to the second question should be smaller than that
i was tryna answer second question sorry, shouldve specified that
but first question could just be that same thing but without the 6! at the end right
so just (12!/(2!^6) * 6!)
that makes 10395
the first question you can think of as number of functions from the set of tasks to the set of people
and there are 6^12 of those
oh yeah u right
and the answer to the second question should be smaller than that right?
but (12!/(2!^6) * 6!)6! > 6^12
yeah probably
i havent rlly learnt much counting theory yet tho so im not too good at it
counting is hard
for #2 would it be C(10,2) * C(8,2) * C(6,2) * C(4,2) * C(2,2) ?
not quite but sounds like a good idea

