Let f(x, y, z) = ... and A = (1, 1, −4).
(a) Specify the tangent plane to the level surface f(x, y, z) = 19 at point A.
(b) At what rate of change f′ v (A) does f increase or decrease in the direction (−6, 2, −3) away from the point A?
(c) In what limits does the directional derivative f′v(A) depending on the departure direction v away from A?
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1 messages · Page 114 of 1
@proper yoke Has your question been resolved?
@proper yoke Has your question been resolved?
𝔸dωn𝓲²s
Hmm okay what does that mean do I put in A=(1,1,-4)?
I think the left is the same as mine
If you do the dot product with the gradient and x-a, y-b, z-c etc
And f(a,b) is my f(A)
I just didnt bother to write f(x_A,y_A,z_A) = f(A) every time
Okay so f(1,1,-4) • (x -1, y-1, z-(-4))?
It's the same as in yours but one dimension higher
Yea but I don’t know how to make that symbol
𝔸dωn𝓲²s
It's your partial derivatives in column vector form
If you do the dot product you get the same what I wrote above
Okay w = fx(A)(x-1) + fy(A)(y-1) + fz(A)(z—4) + f(A)?
yes
Okay do I solve something out now?
f(A) = 19 btw
you nees the partial derivatives, plug A into them and thats it for a)
f_x(A) = f_x(1,1,-4) = ?
And the sams for the others
Wait I’m confused do I plug in 19 on all the f(A)s?
There is only one..
The others are again point A plugged in to the partial derivatives
I cant make it more obv
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radius of the circle?
is that the full question
radius is just 21
@gaunt condor
@gaunt condor Has your question been resolved?
yes
its wrong
then you can apply the formula
you cannot add 12+9
its not parallel
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How do i find the area of a parabola can someone explain and give an example
Are you familiar with integration
@gleaming bluff Has your question been resolved?
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I know these types of questions are easy but I get confused
I found one of the points by plugging in 0
Aand I got (0,-1)
Not 0
-2
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how can i find uncertainty of Q when
$Q=\int_{t_a}^{t_b}-k \left(\left(-12,07e^{-0,0106t}+16,34 \right)-T\right)dt$
Slowaq
i know boudaries of definite integral
k and T are constants
and i know uncertainty of T
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can someone tell me what is a equivalence error in discrete math
i asked for help in this problem earlier and the person corrected it and told me i need to add equivalence errors in each line
he probably means:
Martin
this is the sign of an equivalence
meaning that two statements are equivalent to each other
one could argue that on your paper, you just have a list of statements
if you have a set of statements, you could do it like this:
statement 1
<=> statement 2
<=> statment 3
this would imply that all 3 statements are equivalent
as in, they mean the same thing
so it's pretty much just an equation but with statements
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what gives this equation no real numbers?
its domain is from -inf to inf
Im not sure what that means
the quadratic function has a domain of all real numbers
why is it (-in,in)
do u know what a quadratic looks like
I don't know what you mean
to find a domain don't I factor
that is because there is a quadratic in the denominator
okay
making it a domanin
so not having the top makes it not a real number
therefore (-inf,inf) ??
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Degrees mode - what do you get when you inverse tan that 1.144...?
I was supposed to inverse it this whole time!?!?
wait how do i know when to inverse it ?
use inverse tan function on your calculator
ok
and because you want to get rid of the tan to get theta by itself, so applying the inverse tan gets rid of that for you
ohhh
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which?
also 10 is wrong
kinda
if you start at 2 or 3, that's a different cycle from the other numbers
agreed
@plucky scaffold Has your question been resolved?
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what was that? i didnt see his deleted msg
what happens when u multply dem and num with the (1-root(3))
he insta pinged helper and deleted

rationalise the denominator by multiplying by the conjugate
i realise now my mistake isn't not knowing how to do it but in my working 😭
oops
_basudev
now expand 
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how do you find the missing length on a triangle with the hypotenuse and leg only
right triangle, use Pythagorean
normal triangle, only when you also know the angle of two known sides
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how would you differentiate this? We just learned about power rule, constant multiple rule, product rule, chain rule for powers of polynomials, sum and difference rule. I'm still very confused so I would appreciate any help on this question.
bro I'm so cooked if I keep solving this question
<@&286206848099549185>
@tranquil pine Has your question been resolved?
I mean, if you haven't learned the quotient rule, you can rewrite the question as 1500(1 + 5t(t^2+30)^-1)
That way you can just use product rule and chain rule
This is where I’m stuck
I kept going in circles like this. I don’t even know where I did wrong.
my brain is fried at this point lmao
Lol, it's kinda awkward to type, gimme a second to look at this
Looks like you're right, just make sure to multiply by 1500 at the end still
If you want to check it in the future, the derivative of a fraction f(x)/g(x) is just (f'(x)g(x) - f(x)g'(x))/(g(x)^2)
oh ok, thank you so much. We didn't learn about quotient rule yet so I'll keep that in mind.
Yeah, I got a final derivative of 7500(30-t^2)/(t^2+30)^2 through both methods
ohhh, do you mind showing how you did that?
I haven't arrived at a final answer yet
sure
your answer at the bottom right is correct, you just need to simplify and multiply by the 1500 from the original prompt
1500(f'(x)g(x) - f(x)g'(x))/g(x)^2
(7500(t^2 + 30) - 7500t(2t))/(t^2+30)^2
7500(t^2 + 30 - 2t^2)/(t^2 + 30)^2
7500(30 - t^2)/(t^2 + 30)^2
Jeez, that's kinda ugly to type lmao
thanks a lot bro. It's a lot of work so I appreciate the help.
Nah, I'm just surprised they didn't teach quotient before chain since it's just a formula
Yikes, not even any proofs lol
I mean this is just a summary of all the rules at the end so
proofs were shown in the beginning
anyways, thanks for the help. I'll close this
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np
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When we say the initial velocity is 3i + 4j
What does it actually mean
Kindly represent through a graphing tool like desmos etc
you get a right triangle
x = 3, y = 4
so hypotnuse is 5
and use any inverse trig you like to get the angle
so arcsin(4/5)
so you have a vector having magnitude 5
and the angle of the vector is arcsin(4/5)
that's the velocity vector
you're going 5 units of distance per unit of time initially
and the direction of the distance is given by arcsin(4/5)
Let's say if initial velocity is (1i + 1j)m/s
Then I would be going with 1 m/s in 45°
Right?
no
what is the magnitude of i+j
it's the sqaure root of 1^2 + 1^2
which is sqrt(2)
so you're going sqrt 2 m/s
in 45 degree = pi/4 radians
Ohh yeaahhhh
Correct correct, my bad
Cool, and why in some cases velocity and acceleration are at different angles when both are positive?
in general is accerlation and velocity always equal?
Obviously no
so we shouldn't expect how they're represented to be equal as well
i can have a very small acceleration but a very high velocity
But they should be at equal angles no?
nop, take for example in the real line
if i have an acceleration of 1
my veloctiry should be increasing right?
say my instantaneous velocity is -1 though
so im travelling to the left right now
but if i don't change my acceleration, i will slow down going left, stop completely, then begin travelling to the right
Didn't get, plz explain
are you familiar with derivatives
No
x^2 /2
If v(x) is x^2 then a(x) would be 2x
let's say that im initially going v(0) = -1
How?
wdym how
Nothing, go ahead
chebyshev's infinite pee norm
what is the acceleration and velocities at time x = 1/2?
V = -7/8
And a = 1/2?
yes
so the velocity is going in the negative direction
so it has angle -pi
on the real number line
and acceleration is going in the positive direction
so it has angle pi on the real nubmer line
So i can say velocity is (-7/8)i + 0j
But how does it have -pi angle
It's +pi no?
Yep so basically acceleration is (1/2)I +0j
So 0° with positive x axis
How +pi degree?
@mellow axle
Oh thanks..
But because acceleration is positive, so as time passes
They both will have 0 degrees no?
@mellow axle last question
What exactly is unit vector
Like unit vector of 3i + 4j is 3/5i + 4/5j
But what does it mean
<@&286206848099549185>
@tranquil pine Has your question been resolved?
the hypotenuse is 1
the parallel vector from origin to the unit circle
Oooooooo
Big brain big brain
It makes sense tho...
@tranquil pine Has your question been resolved?
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how do i find the domain of $$f(x) = \frac{1}{\sqrt{4-2x-x^2}}$$
ghiolimer
idk where to start
Factor the denominator
The roots of that polynomial is part of the bounds of the domain
The denominator can not be 0 and the stuff inside sqrt must be positive
Or in other words Domain can be a subset of 4-2x-x²>0
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this is a question on hypothesis testing
I have gotten to $\bar X $~$ N(65, \frac{9^2}{35})$
sealpup321
i cant put squiggly T-T
what are you stuck on exactly?
I dont know where to go from here I am doing 1.a.
null is $\mu = 65$
sealpup321
yep
alternative is $\mu < 65$
sealpup321
yep that’s correct
great 🙂
also by any chance, do you have to check the conditions or no
what do you mean?
to perform a one sample z test, we have to make sure that our sample is random and that the sample size is bigger than 30
btw probably wont change much but we get access to smart calculators so you dont need to use the massive data table
do i do $P(x <= 61.5)$?
sealpup321
on your calculator, do you have an option to do a one sample z test?
because if so i got 0.065
if you can calculate the probability of a normal distribution, you should be able to do that
since i can change the mean and standard deviation I can just change them to 0 and 1 respectively
wait what?
?
can your calculator do a one sample z test or do you have to use normalcdf
is that not how you do a sample test
your calculator should have an option to do one
and all you have to do is just plug in the numbers and the hypotheses
so what did you put in your calculator
this is an online version of the calculator i am using
sorry i know its a bit of a hassle but Im unsure of what you mean
i’m more so asking how did you get the 0.06
ohhhh I just found out that my calculator takes standard deviation not variance
so thats confusing
i see
thatll be why
alright
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Can someone explain to me the range of a matrix and how can I study a matrix with 1 unknown constant value
Show that this matrix range is 3
you need to show that all the column vectors are linearly independent
If range = 3 means it's the the exact matrix right?
No this isn't the range lol
It's the rank
Ye
Say you have a nxm matrix A. Rank(A) is just how many linearly independent column or row vectors you have.
No
Bruh I am really stupid sorry
do you know what linear dependence is?
No can you explain
I think you're just missing the definition
Can you tell me
Okay two vectors are linearly independent when one is the scalar multiple of others.
Is this a vector?
Yes that's also a vector
Ok so give me an example
Do you understand what this means
Of that definition
Can you give like 2 vectors
Say you have 2 vectors u,v. If there exist 2 numbers a,b not equal to 0 such that au+bv=0, then the vectors are linearly dependent. If not then they are linearly independent
Oh
I understand
Geometrically, if the vectors are pointing in the exact same direction (they are on the same line), they're linearly dependent. If they don't, they're linearly independent
Got it
So coming back to the problem
Can you explain range of matrix too
?
imagine your matrix as 3 separate column vectors
Yes
Okay now you use the definition of linear independence to figure out how many of them are linearly dependent from each other
Yep
So now let's see
So I need to check the position one of the first vector with position one of the second
?
what do you mean by that
No
You need to check if there are 3 numbers d,e,f which make the sum of these vectors 0
Oh
Ok
Ideally start with d,e and then f
a - 1/ 2 e + b f + ck = 0
Noooo
This vector is u
This vector is v
This vector is w
Try finding out if there are any numbers d,e such that du+ev=0
Yes
How do I find the constant after
Just by thinking of some numbers?
You need to construct a system of equations
So I make the third
So for vectors u,v and numbers d,e:
d(a-1/2)+ec=0
db+e(a-1/2)= 0
dc+eb=0
So u took the first vector
And made the sum adding a
Constant
And = 0
Ok
So you check
The dependency
Yeah you sum the multiples of their components and check if they can equal 0
Yes
In this case you can immediately see that you simply can't multiply u with any number to get v or w and vice versa so therefore the matrix has full rank
But it's a good exercise
I have to do that for every other vector (in my case the other vector have same components
Do it's easier
So*
Here
But in a hard cases do I need to that for every vector?
well to prove it you need to show that they're all linearly (in)dependent
but if you know that u,v are linearly dependent and w is linearly independent, then you know that both u and v are linearly independent from w
Beginning the linear algebra series with the basics.
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Correction: 6:52, the screen should show [x1, y1] + [x2, y2] = [x1+x2, y1+y2]
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Fu...
watch this series andyou will understand immediately what i mean
After I look
best if u look through the series at least up to ch 4
Ok
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can anyone help me with this 3. Given the quadratic and linear equations below, determine the point(s) of intersection
using 2 different algebraic methods. Hint: remember systems of linear equations from
grade 10)
i. X
2
– 2x + 3y + 6 = 0
ii. 2x + 3y + 6 = 0
Have you tried anything?
yes
i tried to subsitute them
to equal each other
and i ended up with x^2 - 4x + 0
but im prtty sure that is not the right answer
Are you able to send a picture of your work?
Ah thanks
Well, i don‘t see an issue with doing it this way, did you go all the way through with that method?
i think so i again i got to x^2 - 4x
Also, i think you put a + instead of an =
after thee 6?
After x^2-4x
oh yeah
i dont know if that answer would be right because guath math gave me different answer but i want to understand it
also how would i get the coordinates from x^2-4x
You get the x coordinate from x^2-4x=0
what would it tbe
I don‘t know, solve for x
ok one sec
i just factored out x
im not sure if that would work but my x coordinate is there now
Hm? What are the possibles values of x if you know x(x-4) = 0. there are 2
0 and 4?
Correct. So your x coordinate is either 0 or 4. You‘re gonna have to try them afterwards. But now you can use this to find the possible y coordinates
ok so i would plug both into the equation i found?
What do you mean by "equation I found"?
Well, you know X, and you want to find Y. Do you know of any equations in this problem that connect X and Y together?
No, because in this the y cancel out, so there‘s no point. But if you pick one that the question gives you, you‘ll be fine
ok
let me do it ill send a photo in a second
so far i got this
before i go any further im just wondering if the steps are good so far
So, you picked equation I and plugged 0 for X?
yes
Then you‘re on the right track
ok ill finish it and send
i got y=2
for that equation so my first intercept would be
(0,2) right?
You had 3y = 0 and you found y=2?
sorry i miss wrote it
it is 3y=-6
because there was a +6
iso i moved it over and divided it by 3
And -6/3 is?
:p
Okay, so one potential intersection is (0, -2). Now you had another X point so you have to try that one as well
Great, so you have 2 potential intersections now. Last thing to do is plug them in the equation that you haven‘t used to make sure they work
Well, you have 2 points, which do work in the first equation, the one with x^2. but you need to check i. The other
Nice! Well then you‘ve found the 2 points
Yeah it‘s possible. When you think about it, you have a parabola and a line
So it‘s very possible that the line cuts the parabola in 2 places
ok thank you sm
can i give you like a vouch or somethingg this is my first ttime using the server
I don‘t think this server has a reputation bot or somwthing like that, but thanks I appreciate it :)
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I have a coding problem. I am looking to find the coordinates of an area in a grid. Currently I am doing something like this:
Corner1 = 10, 0, 10 (x, y, z)
Corner2 = 20, 0, 20
Area = Corner2 - Corner1
BlocksPerArea = 10
Block = Area / BlocksPerArea
This means that Block = 1, 0, 1
and when block is multiplied (1, 2, 3, 4, etc up to 10) I recieve a number of 1, 0, 1 | 2, 0, 2 | 3, 0, 3 etc... However I need to get the numbers of 1, 0, 1 | 1, 0, 2 | 1, 0, 3 | etc...
I am not really sure how to go about this thanks
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Am I correct in saying the following
For any $n$-tuple of natural number $v=(v_1 \ldots v_n)$ it can be mapped to the natural numbers via the mapping $$\prod^{n}_{i=1}p^{v_i}_n$$ where $p_n$ is the $n^{\text{th}}$ prime number. So $p_1 = 2, p_2 = 3$. This is true the via "unique factorization theorem".
Br;an
this for a formal logic course, im trying to write it more formally but i think i might have might have left some parts ambigious i.e. i dont know if this a mapping or it actualyl does work to being with
are you claiming that this mapping is a bijection?
or are you just saying you can make this map
hmm just a map with no restrictions
i think it would have to be injective
tho
but then i would have to show that?
my objective was to prove that all n-tuples can be mapped to the naturals numbers
well if you're writing a proof for something then yeah you generally want to prove your claims
as in there exists a map $f : X \to \mathbb{N}$
Br;an
where X is any n-tuple of natural numbers
i think thats equilvnent to what i want to prove
if there's no conditions that f need to satisfy there are many maps that can take an n-tuple to a natural number
so if i can demonstrate one of them exists does that also mean my orignial statment is true (the statement being "that all n-tuples can be mapped to the naturals numbers")
yeah
based
and i think you using the prime decomposition is overthinking it
just take $f:\mathbb N^n \rightarrow \mathbb N,f(x) = 1$
chebyshev's infinite pee norm
ohhh okay
my orginal statement was flawed then
actually i was trying to show that the set of all n-tuples for some specific is countable
hence why i said there exist a map from that (the n-tuples for a specific n) the naturals?
n-tuples for some specific is countable
do you mean for some specific set is countable?
all sets of sets of n-tuples? so like all 2-tuples are countable and all 3-tuples are countable indivdiually
not all at once
but
with one proof
ok well
if that makes sense
first of all
to show a set is countable, you need a bijection with N
not just any random mapping
second of all
probably induction
huh, oh right cause i could just map the same element if were not injective
yes
that or just show the product of countable sets is countable
product of a countable sets as in cartesian prodcut?
yea
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2+2=5?
Please don't troll
obviously
<@&268886789983436800> troller detected!
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i need to find CD and area of the quadrangle
im kind of stuck, the only thing i was able to find was BD which is root of 189 and AC which is root of 37
AD is 12 AB is 3 BC is 4 and there are only 2 of these angles given
nothing else
@tired glen Has your question been resolved?
<@&286206848099549185>
how did you get to these values?
from the law of cosines
<@&286206848099549185>
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how is this 0?
2k+1 is odd
which means u will be at an odd step
but that would have taken u even steps to get to that odd step
I'd post the original example but it seems like you're moving on a number line so you'll only hit even numbers at even timesteps
x1 is the first step
x2k+1 is odd step
ie 3 5 7 9 etc
to go from 1 to an odd step
u need to have taken an even number of steps
or bets
by the example
yh so my point is that it should only = 0 when the number of steps is odd
ie
yes
if thats 2k
than 2k - 1 ( the first step)
is an odd number of steps
however
going by this
we can only return after an even number of steps
hence
that probability would be 0
do u see my point?
but like clearly it alternates between nonzero and 0
yh
idk what X is yet
example 3.3 I think
sry]
oh ok
heres the next part
but this doesnt make sense
2k bets havent happened
in facts 2k-1 bets have happened no?
since X1 is the initial state
yea there's some weird consideration for if you're doing it after or before a bet
that changes things from even to odd
the way they do it only works if we define X0 instead of X1
here it's before where usually I'd write it as after I think
calling the first step 1 instead of 0 is also a convention so it's annoying to sort which is which lol
before first bet means even number of wins/losses
oh i see
@sturdy cloak Has your question been resolved?
sry quic question
how is the expectation equal to this?
same question as op
each visit is +1 to N_0
ye
but isnt by definition the expectation the sum of each likehood of on outcome multiplied by its respective outcome?
but here we r just adding probabilities
each time is like 1*P(x=0) + 0*P(x!=0)
oh yh cuz the possible outcomes r only 0 and 1
yh kl makes sense
thanks
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how am i supposed to solve w/o a function?
this is the question sorry
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am i correct with everything here?
please let me kno
it looks right to me just need someone to verify
<@&286206848099549185>
is that a minus or an equals?
If its an equals then yes that is correct
but unholy levels of inefficient
eh solve using matrices, yeah ig u did it the right way
meant in main problem
i know y = -2
if its an equals
because we have
2x +7y = 4
2x +6y = 6
subtract bottom from top
for y = -2
solved
teacher doing u guys dirty if theyre not allowing that
ohh yeah equals
well i think they are i'm just following a help vid they sent me
same problem basically with diff numbers
yeah I recommend seeking the best way first
because it goes from this to literally 3 lines
is this way easier
yes just like in algebra 2 you can cancel out things in a system of equations
you multiply out the matrix for
[2x +7y] = [4]
[2x +6y] = [6]
and then just "subtract bottom row from top row"
you know its an option when one of the variables is cancellable
like 2x = 2x
damn i see what u mean
hell even if it was like
way easier
[4x +7y] = [4]
[2x +6y] = [6]
yeahh
u can say "subtract 2x the bottom row from top row"
wow ok
thatll give u some constant*y = something
solve for y
if u need x then u can just plug in for y and isolate x
bol on future questions 👍
like i had a similar one i just did 20 mins ago and it was so much
had to solve for x and y tho
ty for that man
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Jaxx
does this make sense
then distribute r and use the identities that x=rcost and y=rsint
yeah
in the future find ways to group r together with sin and cos
that way you can use the identities
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help
I need help figure out what to put into this simlarity I have been on it for forever
.
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Wait what’s the correct path of multiplying?
If I have
3x + 3
Times 5x + 2
——————————-
Would I do 3 times 2 and then 3x times 2 and then 5x times 3 or 3x times 5x next?
you do all of those
the order doesnt matter, just make sure you combine like terms in the end
Oh ok
Thx
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I don’t know what i did
@sage kindle Has your question been resolved?
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y''+2y'+2y=0 y(0)=0 y'(0)=pi
is c1=0 and c2=pi?
what are c1 and c2? need more context
so plug in y(0) = 0 you indeed get that -c1 = 0 so c1 = 0
and then compute y'
y'(t) = c2e^(-t)(cos(t)-sin(t))
but now that y'(0) = pi, it means -c2 = pi...
so c2 = -pi
wait let me see where i messed up
ok i havent
so basically
pi=-1(c1·1+c2·0)+1(-c1·0+c2·1)
pi=-1·c1+c2·1
pi=-c1+c2
pi=0+c2
pi=c2
@scarlet sequoia
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my bad forgot a minus
this is y'
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Determine the dimension of the column space of matrix A
Don't know if my calculations are right
,w rref {{1,-4,-3,-4},{3,4,-9,4},{-7,-7,21,-7},{5,-4,-15,-4}}
Seems like there may have been some issues in your row reduction
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In geometry, what does it mean when senθ = 0,60 and cosθ = 0,80? I need the degrees to solve a certain exercise but im not sure what this means
@bold jungle Has your question been resolved?
Im not quite sure, i know the hyp is 5, so in this case would i just like, cosθ = adj/5,
and then adj = 5 . 0,8?
yep
inverse cosine i suppose
That sounds very disturbing so ill just stick with what the exercise asked me, thank you for helping tho
np 
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Hello
I'm trying to write a bot to play nim perfectly. I'm using multiple heaps with a restriction of only taking 1 or 2 tokens at a time under normal play.
If I do it without a limit my code works perfectly fine however I'm struggling to impose the limit correctly.
I'm following this part on the wiki page, they call it the subtraction game: https://en.wikipedia.org/wiki/Nim#The_subtraction_game
As far as I can tell all I need to do is:
- Takes all the piles, mod them by 3 (grundy number)
- Nim sum them by xoring them together
- Check the total off all the piles after modding them by 3, if equal to 0 then treat the nim sum as 1
- Find any pile where nimSum xored with pile < the pile count and remove the extra tokens from there
I think that sums up my issue, I'm really not sure what goes wrong. Any help would be appreciated
Nim is a mathematical game of strategy in which two players take turns removing (or "nimming") objects from distinct heaps or piles. On each turn, a player must remove at least one object, and may remove any number of objects provided they all come from the same heap or pile. Depending on the version being played, the goal of the game is either ...
@glossy pewter Has your question been resolved?
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@glossy pewter Has your question been resolved?
How have you implemented this strategy?
If you send your code, maybe you could work out what goes wrong
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wondering if correct
i don't think either are correct
how should they be worked?
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hii, this is 8th grade math, don't come for me, but i need help. The first one asks for the green area, and the 2nd one asks for the green area perimeter (has options), could someone help?
You just need to break it into parts.
The end caps are semi circles so put together they are just a circles area. The inside bit is a square - circle
So if you can work out the area/perimiter of a circle and square you got it 🙂
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what is diracdelta(0) is it 1 or infinity
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Please don't occupy multiple help channels.
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Just use implicit differentiation right
Just go for it yeah
yeh and a crapton of product and chain rule
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help me
Okay let's see
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Flux Fissionist
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how is the divisor 1200 when the cost is $1.80
the bottle is 1.2 L, and that costs 1.80
dividing it by the size of the bottle you get the price per L
@novel walrus Has your question been resolved?
well how would you find x
by dividing
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✅
@supple jolt by dividing right
yeah
set up fractions
simply draw a fraction line between the first and second equation
Oogy Boogy
ok
how about this one
i divided 54 by $8.10 which gave me 0.15
and then divided 1000 by 1300 which gave me $13
@novel walrus Has your question been resolved?
1KG - 13.00
