#help-49
1 messages · Page 50 of 1
Well, you want to change the expression
[
(\frac{3n + 2}{3n + 1}) \ln(a_n) = (\frac{3 + \frac2n}{3 + \frac1n}) \ln(a_n)
]
so that inside it, you'll see a $\frac1n \ln(a_n) = \ln(\sqrt[n]{a_n})$
what can you multiply and divide by to make that happen?
@tribal temple
Well multiply and divide by n, sure-
then wat
That then gets you
[
n \cdot {\color{green} \qty( \frac{3 + \frac2n}{3 + \frac1n}) } \cdot {\color{red} \frac1n \ln(a_n) }
]
@tribal temple
And you said the green goes to 1, and the red goes to ln(4), right?
but n is blowing up to infinity, and ln(4) is strictly greater than 0, soooooo...?
Yep, left hand side of here diverges to infinity, so b_n must do too
how do i check my answer doe, is it possible
I mean, other than arguing through logic, without an explicit sequence it's pretty hard to in this case
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how is the derivative of g(x) 2,4,6,etc when the first difference is 3,5,7,9,11?
<@&286206848099549185>
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ok sorry but can you help me pls
whats the derivative of g(x) ?
i know the first difference is 3, then 5, then 7, then 9, then 11
so i just don't understand how then a derivative of this function ends up being 1 less then each of those first differences
like for a linier function, i see how the derivative is the first differenc3e
calc the derivative it will be clear
so is each of those derivatives for the quadratic the tangent line? like the slope of each of those points?
yes
but g(x) describes a quadratic functions whilst g'(x) describes a linear function
so when u calculate the values given one will go up faster than the other
ok igu
,w derive x^2-9
ok
@brittle spade Has your question been resolved?
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what steps do u think u know ?
thats for a normal function yes
oh
here ist just an equation
u want to have F in one part and then all the rest in the other part
give that a try
thx
show what u got when ur done
so im isolating f?
yeah
-5/9F=-c-17 and 7/9
$-5/9f=-c-17 7/9$
chilly
it should be 17 7/9
$17 7/9$
chilly
wdym ?
the 7/9 is with the -17
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spookyspaghetti
like this
@austere lodge
sending a pic
ait
yeah so multiply
oh
welp doesnt rly matter cus its not completely the right answer
how should I do it?
you start with $C = \frac{5}{9}(F-32)$
spookyspaghetti
yes
oh
that gives $\frac{9}{5}C = F-32$
spookyspaghetti
correct ? @austere lodge
correct
alright then whats the last step to only get F on the right side ?
add 32
add it where ?
the left side
so $\frac{9}{5}C+32 = F-32$ ?
spookyspaghetti
so u add it on both sides then
yes
important to specify that
oh
then ur left with $\frac{9}{5}C+32 = F$
spookyspaghetti
yes?
now u have a function of $F$ with respect to $C$
spookyspaghetti
thats the solution that they are asking for
i will
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yo
<@&286206848099549185>
which rule?
@runic sage Has your question been resolved?
the rule where they change it to lim
idk what or how they did that
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for a continous random variable, is it strictly defined to be (-inf, inf) or a disjoint closed union? (as an example, [0,10] U [70,90]
so if it was [0, inf) it would be discrete random variable? This is a stats question by the way
wait what
why is that
How can it be discrete if it's from a continuous set?
oh so its continous if it consists of all numbers in an interval?
oh so like what we learned in analysis
its the same thing
ooh im stupid
Also e.g. the exponential distribution is continuous and has [0, infty) as where it's defined
Stats too
It should be connected to the bin 
honestly, Im sort of agreeing
for now
its not very concrete..?
stats is so.... random😂 thats the way I'd describe it rn
Random variables 
Stats roolz
@obtuse totem Has your question been resolved?
ive got an interesting question
a,b
So at first, I thought 0 could be a possible value for X right? Because X denotes the number of moves BEFORE returning to 0. So if Claudius never makes any move he's never returning to 0
but 0 is not in the set of X in the solution
and one other value I thought of was 1, because the first move must always be B1,B2,B3,orB4. and then the 2nd move theres a chance of returning to 0
so my set for X is {0,1,2,..} but thats wrong?
ohh i see
X is saying nunber of moves, and after moving to either B1,B2,B3,B4 Claudius has to make another move after to see whether he goes to 0 or not
so that would be 2 moves
not counting 0, the set would be {2,4,6,8..}
I think so
ye the answer says {2,4,6,..}
I think I have the right interpretation of why that is
@obtuse totem Has your question been resolved?
.close
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How does one go about evaluating the following limit to find the derivative of sin(sqrt(x)) using first principles?
I have tried using the sum-to-product formulae but didn't know what I could do to simplify the expression further.
I was wondering about using small-angle approximation but that doesn't make much sense.... x may not be small and I don't think it is safe to make the assumption.
(I explicitly don't want to use L'Hopital's rule here, ruins the fun for me if I use these "shortcuts" 😂)
@elder prawn Has your question been resolved?
$sin(A) - sin(B) = 2sin((A-B)/2)cos((A+B)/2)$
Diborane
I have tried using the sum-to-product formulae
rationalise it so now it becomes
$2sin(h/2(sqrt(x+h) - sqrt(x)))cos(sqrt(x+h) + sqrt(x))$
Diborane
then evaluate
sorry is sqrt(x+h) + sqrt(x)
$2\cos{\frac{\sqrt{x + h} + \sqrt{x}}{2}}\sin{\frac{\sqrt{x + h} - \sqrt{x}}{2}}$
HTGAzureX1212.
you missed multiplying the entire thing by 2
but yes its correct otherwise
ah yeah
now multiply and divide 2(sqrt(x+h) + sqrt(x)) with the h in the denominator
then the limit would be of the form lim x -> 0 of sinx/x =1
oh sin x / x
yeah
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It says as the angle gets smaller the adjacent size gets larger
How is this possible if just the hypotenuse is moving
Oh no I understand
My bad
.close
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i'm marking my physics practice test
and the question was
"a small aluminium ball is statically charged with - x C. The aluminium ball is suspended in an external uniform vertical electric field."
there was mass and charge but its not important
"Draw the external electric frield, indicated at least 4 field lines"
i have no idea what this looks like, and the answers only say "draws electric field direction and shape" as a marking guide, it doesnt show me what the field looks like
can someone please help
well we know the electric field is uniform
in order to keep the ball suspended in the air, it should be in a particular direction to counteract the force of gravity
@median ridge Has your question been resolved?
yes i know
but given that the ball is in the middle and its statically charged negatively, does the electric field interact at all with this?
well the force from an electric field is $\va F_E = q\va E$ (since the field is uniform, the same force applies to the entire ball)
cloud
so is it just like electric field lines through the ball? i get mixed up with magnetic field lines because they curve due to the ball
it just says "draw the external electric field", not the field of the ball itself
so its a bit of a trick question? its just a normal electric field? not impacted by the charge of the ball at all?
just like that?
well if the ball was positive vs negative that would change which direction the field would need to be
because its suspended, the positive plate would be at the top yes? because the negative ball is attracted to it and repelled from negative
you can think of it that way
ok cool thank you
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hey]
got a terms question
state the four first terms
Tn = 4n - 3
how am I meant to know the term when the question doesnt state t1 nor n
Just substitute n=1,2,3,4
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Proof by contradiction question, how would i start this off?
i meaan i know the assumption but how would i contradict the assumption?
What would be your assumption
@vagrant storm Has your question been resolved?
Okay, now break down the assumption. How are stationary points defined?
what do u get?
a stationary point means that after differentiating its value will be 0
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hello
hello
k
So when im finding a rule for the nth term
how do i go beyond this point
wdym?
after ive found out tn=2700+(n-1)x150
what do I do
because I thought you just leave it at that
is tn the sum of an ap?
yes
do you want to find the nth term of ap?
no im just trynna figure out why question c
does =2700-150n+150
are you always meant to simplify an explicit rule
not alwys depend on the question
i just dont get the simplifying in this case
well its more simple in terms of n than n-1
They're both different ways of writing the same expression
we just simplify because it looks nicer and simpler
yes i know but how does the simplyfing work in this equation
its just more elegant to look at
the distributive law?
bruh
I really don't get your question
okay so how does it go from tn= 2700 + (n-1)x-150 to 2700 - 150n + 150
distributive law
well its by the distributive law, you distribute -150 over the bracket
ie, you multiply each term in the brackets by -150
so it becomes n*(-150)+(-1)(-150)
-1 * -150 is just 150
so it becomes -150n+150
oh wait
i thought you could only do that if the number was infront of the bracket
e.g. -150(n-1)
multiplication is commutative, it doesnt matter whether the number is before or after
you can rearrange the bracket and the number in any order you'd like
I had no clue
$ab = ba$
proofAd
alright, dont forget to do .close
.close
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do u have idea on limit of summation?
do not ping until no one responds atleast for 15min
<@&268886789983436800>
well lim as n approach infinit(summation (k/n0)^4*1/n is = integral 0 to 1 x^4
lol bro got hacked ig
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im following a problem on quadratics and in the first step he factors the problem without really explaining how he did it. can someone break it down how he did it?
firstly, observe that (or test a couple numbers until you spot that) x = -2 is a root. So (x+2) is a factor of x^3+8.
Then use algebraic/long division
i can understand how he got the x + 2, because he did square root of 3 on both sides i think
but how does he get (x^2 - 2x + 4) from the (x+4)
cube root*
like can i get a step by step, im strugglign in math here
of how he got the 2nd part
the method is algebraic/long division
if you don't know what that is, I advide looking on yt
what would i look up specifically to figure out how he got that?
it's hard to explain how that works without writing on a piece of paper and going through it step by step
Is the sum of cubes
oh yh that ^ also
8 = 2^3
either look up sum of cubes, or just google "algebraic/long division" and learn the general method, then apply it to the question. No shortcut
ohh ok
i found the exact problem
he just used that formula
A^2 - AB + B^2
for the 2nd part
yh
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✅
Hi i had a quick question while doing my homework
When i did the problem: x^3 - 64 = 0
When i factored it out
I got ( x - 4 ) ( x^2 - 4x + 16 )
but in google it says
( x - 4 ) ( x^2 + 4x + 16 )
so the difference is that google is 4x while i have -4x
but why would it be positive?
$$a^3 - b^3 = (a-b)(a^2 + ab + b^2)$$
JustToPro
well do the foiling/multiplication out, or use the formula :3
:3
based on @torn compass 's formula,
a = x
b = -4
so (a - b) would be (x +4) then?
but the issue is, in the video i watched it said the formula is (a + b)
you can use that formula too, with b=-4
u will get same answer
I noticed that in his problem, the A^3 + B^3 are added together
but in my problem it's subtracted
does that make a difference?
can i sitll use the same formula he used
u can
but u need to use a = x and b = -4
$$x^3 - 4^3 = x^3 + (-4^3)$$
JustToPro
a = x
b = -4
OHH i see
so i just want to confirm
i can use the formula in the video i sent regardless of if the problem is:
x^3 - 64 = 0 / x^3 + 64 = 0?
yes
so the addition or subtraction doesnt matter since if its subtracting b is negative instead
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isn't this outright wrong. like if epsilon_n = 1 for all n then its just a geometric series that evaluates to 1.5?
,w sum n=0 to infinity of 1/3^n
index should start at 1
@slender cobalt Has your question been resolved?
ah so its a book error, thought so thnx for the help
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So for this I end up getting [
\6\FF\omega = \412\6\delta\omega - \sum_{\substack{n=2k+1\ \ k \in \Z \ n\ne 0}} \4j{n\pi}\6\delta{\omega - n}
]
I am not sure if thats correct though. i decomposed the sequence into even and odd parts and got that
,w fourier transform of HeavisideTheta[x] - HeavisideTheta[x-pi]
that doesnt look very delta to me
well like
what i did is like
,, c_n = \41T\int_0^T\6fte^{-jn\omega_0t}\dd t =\4j{2\pi n}\8{e^{-jn\pi}-1}
so like
,, [2\textwidth] c_n = \41T\int_0^T\6fte^{-jn\omega_0t}\dd t =\4j{2\pi n}\8{e^{-jn\pi}-1} =\4j{2\pi n}\8{(-1)^n-1} = \e{dcases*}{0, &if $n = 2k\q k \in \Z$ \ \5{-j}{n\pi}, &if $n=2k+1\q k \in \Z, n \ne 0$}

what is this integral for
this looks like fourier series
ew
well this is quite disgusting
Quite.
god what even are the scaling factors
well
its probably somewhere in the vicinity of correct
but im too lazy to work out the fourier series
actually i literally have the formula i was doing it yesterday
,, a_k = \f 1 {2\pi} \int_0^\pi e^{-ik\theta} \dd\theta = \f 1 {2\pi} \f 1 {-ik} (e^{-ik\pi} - 1)
,, a_k = -\f 1 {2\pi ik} ((-1)^k -1)
,, a_{2k + 1} = \f 1 {2\pi i(2k + 1)}
,, a_0 = \f 1 {2\pi} \int_0^\pi \dd\theta = \f12
,, f(t) = \f12 + \f 1 {\pi i} \sum_{k \in \Z} \f {e^{i(2k + 1)t}} {(2k + 1)}
@last slate Has your question been resolved?
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why can we define the set of complex numbers equals to the set of 2x2 matrix such as $M =
\begin{array}{cc}
a & -b \
b & a\
\end{array}$ with $(a,b) \in R²$ and how to prove that ?
phoestaclies
@pulsar sun Has your question been resolved?
Because they possess the same algebraic structure under addition and multiplication
If you want to be morqe formal,
The ring of complex numbers is isomorphic to the ring of those matrices
@pulsar sun Has your question been resolved?
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Hi, is this overall correct? The question: if 3sinx+4cosx=5 find sinx, cosx
u forgot to square the 3 in hte denominator
but yea otherwise i think its ok
Okay i will just send how i did it just in case
aight
Ou
...well that's one stupid mistake
9/15=sinx
That's it
Lol
Thank you anyway
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could i get some help please
send the questions you need help with
.reopen
its already open lol
how do i reopen it
oh ok
i dont actually know if it is possible
@keen seal do you know this
you have no angles no measurements nothing?
no i dont think so
are angle ABC the same?
we are given that they are integers
they cant be
but i guess it could be possible that 2 of them are
<@&286206848099549185>
OH WAIT @keen seal i messed up and found the question
m=3,n=4,p=12...idk i think this is it
however that isn't P at its largest
soo is it the minimum?i found it idk
it could be the minimum
is it 1/2=1/m+1/n+1/p
where did u get that from
and i give values fpr m,n,p but there has to be a better way
soo u get the interior angles in a k-gon
==>180-360/k=thetha K
soo thetaK+thetaM+thethaM=360
(180-360/m)+(180-360/n)+(180-360/p)=360
540-(360/m+360/n+360/p)=360
subtract 360
180=360/m+360/n+360/p
divide by 360
1/2=1/m+1/n+1/p
and then how do you get the maximum
@ivory saddle Has your question been resolved?
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Can someone please explain the 2nd step. I didn't understand how they got that value in the numerator. I understood the denominator part.
,rotate
how did they get the denominator part?
you cant do that
Can someone please explain how to solve this?
x^2 - y^2 = (x + y) (x - y)
looks like they mutiplied the top and bottom by the numerator
try to see pattern and set x, y for something
and remind yourself that ( sqrt(a+2b) )^2 = a + 2b
Oh so rationalizing?
ye
Alright
Thanks you all
i would honestly
try to set
u=a+2b
and other constant
like z=a-2b
to help you
rationalize
@last slate
Alright ill solve once and ill show
Thank you so much everyone.
@fickle oriole thanks
Can i dm you if i have doubts? Im a lil self conscious to post my doubts here. I understand if im not allowed to do that.
Thanks a lot.
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Is anyone able to proofread this for me rq? I haven't done a set proof in about a year, so I just wanted to make sure it sounded ok.
I didn't grab the entire thing.
you need to chope it up to pieces.
where black orange and red are the same or B is greater than A
hoping no error made
A interset B = A then A is subset of B.
Proof,
Assume A intercept B = A.
Let x be some element in A.
Then if we can prove that x is also in B then we will have proven that A is subset of B. because it can only happens if A is subset of B
Since x is in A then it means that x is in A intercept B. which means x is in both A and B.
So x is also in B.
||We proved it.||
Is that not what I put, or are you saying I need to write it differently?
Just trying to understand the thought process because in my mind, we wrote the same thing.
Am I able to say that If $x\in A, x\in A\cap B$, by the def of an intersection?
Narutoes
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using either ratio or root test
im left with (x-2)/2
and theres no n so is this still fine?
well hopefully you are able to find the limit of a constant
using the root or ratio test you should be left with $\abs{\frac{x-2}{2}} < 1$ (since that is the limit you calculated)
cloud
(in particular, where are your absolute values
)
i absolutely forgot them
okay so -1 < x < 3
right? O_O

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.(also this one does happen to come under the geometric case [which is why you can automatically exclude the endpoints!])
ah so whenever geometric you exclude endpoints?
wait oh yeah i can see what you mean
.Yep, though not exclusive to geometric ofc 
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Yep, -1, and of course that series doesn't converge
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How can I integrate this?
from inside out.
integral of (your func) from 0 to 2 with dn first.
cos( theta) is just a constant then.
and then integral of (your func) from 0 to pi/2 with d theta.
My bad, it's dr, but how can I integrate r(sqrt(4-r^2cos^2(theta))
Variable change or something else?
its r * sqrt(4-r^2) * sqrt(cos^2(theta))= is constant.
try u v = u dv - v du.
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Greetings
Is
$\
\sqrt{\frac{x}{y}}=\frac{\sqrt{x}}{\sqrt{y}}$
GinNBread
True for complex numbers
What is i/i?
Yes it is
I don't know. Someone told me some rules of algebra that we apply to real numbers are not applicable to complex numbers
You can take two numbers
x= a+ib and
y= a'+ib' to verify
Some does not mean all
That's why I asked
Actually nvm
The polar form will be an easier approach
wait. √(e^(ix)) is e^(ix/2) right?
Yes
It doesnt
Or is that operation even valid 😭
And it does
It does?
sqrt(e^(2pi*i)) = 1, e^(pi*i) = -1
sqrt(-i)= 1/sqrt(2) - i/sqrt(2)
sqrt(i)= 1/sqrt(2) + i/sqrt(2)
Divide em both, I think you should get the same on both sides
You get -i here
U get i and -i, dont u?
and i with sqrt(-1)
Hmm
The original question is true for complex set but real numbers
?
In this case x, y must be reals
Nvm then
What?
What does this mean?
sqrt(-1/-1) = sqrt(-1) / sqrt(-1)?
Yes
oh, if we are working with the real numbers but with complex operation, then yes
Exactly
Bro 😭
the problem is that the principal square root only takes the solution with smallest argument. So e.g x^2 = -1 has solutions i and -i, but sqrt(-1) = i, because it has smaller argument
The reason why sqrt(-i / i) = sqrt(-i) / sqrt(i) didnt work is that the first one took the solution with smaller argument, while the second one took the solution with larger argument
What do we mean by larger argument?
but essentially, they are both solutions to one quadratic equation
do you know polar coordinates?
Yes
argument is the angle basically
sqrt(z) returns a solution of z^2 = x, but there are always 2 solutions (except z = 0), so it returns the one solution that has smaller argument
or equivalently stated, that has positive coefficient of i
But larger as in?
Smaller "argument"?
out of the 2 solutions, one has smaller angle in polar coordinates
Ok, that makes sense
and sqrt(z) returns that one
Hang on so while finding sqrt(-i), if we take the arg as 3pi/2 instead of -pi/2, it comes out to be a diff value
Indeed it does
hmm
As I said, there are always 2 solutions to z^2 = x, except for z = 0
this is an example of 2 solutions of z^2 = x
note that they are always symmetric about the origin
I never knew square root returned the one with lesser argument, that clears so much up.
and what square root does is it only returns the one in upper half of the plane, that is the one with smaller argument
If we could just choose any argument, then sqrt wouldnt be a function anymore
Right
because it would return 2 values for 1 z
And this is exactly the reason why some rules dont work in complex numbers
So we neglect the one with the larger arg?
Like sqrt(+4)= 2 and not -2?
because we can sometimes manipulate it, such that one returns the 1st solution and the other the 2nd solution
yep, this was also done with reals
sqrt(4) = 2
not -2
Makes sense now
To generalize, we can say that either
sqrt(a/b) = sqrt(a)/sqrt(b)
Or
sqrt(a/b) = -sqrt(a)/sqrt(b)
so they are either equal, or one is equal to the negative of the other
Idts not necessarily upper half
Coz for example sqrt(-i), both solutions are in 3rd and 4th quadrants
Oh wait nvm
I miscalculated
there are always 2 solutions of form: z, -z. So they always lie in opposite quadrants. It makes sense because z^2 = (-z)^2
Yeah mb
and there cant be more than 2 solutions for quadratic equation
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Show that if :
@last slate Has your question been resolved?
<@&286206848099549185>
You need to justify going from line 2 to 3
Yes, you do have to justify it
I'm sorry?
You need to justify your steps if they are not based purely on definitions
I proved x belongs to C-A. I need to show that it is the proper superset of C-B
You're telling me I missed something?
Yes. You're missing the justification for going from line 2 to line 3
I have, no? On the right side I wrote since a is the proper subset of b
Have you proven that?
I'm asking this because other friends of mine simply concluded with
C-B proper subset of C-A
It is given A is the proper subset of B, I'm confused.
Could you give a proof for this question, please?
Yes, but have you proven (or has your book or teacher) that "x not in B" implies "x not in A"?
Not if it has been proven for you
It's pretty much done IMO
You could let x be an element of B not in A. Then it's in C - A, but not C - B. So the sets can't be equal
I feel it's incomplete
If you wanted
No I mean I could yap and finish
But isn't there a simpler way
Like the other steps
Simpler than what
You know complete it in a single line
That should not be the goal and is not going to be possible in general
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no exact solution
For the given problem
Since in essence the transversal lines in the problem do absolutely nothing
as the only given information is in the interior triangle and the information we want to find is in the interior triangle
with 1 angle it should be impossible
Which second one? Where am I looking?
The second triangle
the second question
in the picture
Ignore all extra info
Pretend that just x and 46 are in the diagram
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<@&286206848099549185>
whats the question?
Second question
Solve for x
Only given is 46
Isn’t this question absurd?
impossible
is 46 really the only given? no parallels or anything like that?
well, x+46=b, that might be helpful
@sullen aspen Has your question been resolved?
Well the parallel line is outside the triangle with all the info
it’s like “noise”
provides nothing
to the problem
I can imagine u can just isolate the triangle itself and that’d be the same exact problem as what’s going on here
Well, the task isn't to find x, but find the calculations needed to get to x
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I need help with this kinematics as I tried my best wit this
<@&286206848099549185>
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Sorry
Since the initial vertical velocity upwards will be the same (but with opposite sign) as the vertical velocity downwards when the diver is at a height of 2.00 m, u can 1) find the velocity at the halfway distance in question in the problem using the time given, a distance of 1, and -g (this is basically like finding v0); and 2) find the downwards vertical velocity at a height of 2.0 m using a distance of 1, an acceleration of -g, and a final velocity of the velocity u just calculated
the answer you obtain for this downwards velocity will be the same in magnitude as the initial velocity upwards
giving u the answer to the question
Need help with the equations
For 1), use -1 = v_halfway (0.12) - 0.5 ( 10) (0.12)^2
For 2), use v^2 = (v_halfway)^2 - 2(10)(1)
v_halfway will be calculated from 1
1)*
Yep your initial equation looks good
I’ll assume the arithmetic is right past that
Continue
that is your halfway velocity
Yes but you should probably be consistent with your value of g
I used 10
you used 9.8 and 10
Alright that should be the answer
Yep
Thank you
No problem
Have a good one and thank you as I will keep asking for help her
Sit I got another one
You too. Also kinematics?
Ah I haven’t covered this yet I’ve only taken mechanics
But currently taking electromagnetism so this should come up soon
That is okay as thank you for your help
@ the helpers
Hope to get help like this <@&286206848099549185>
👍🏻
Are you a physics major
I think you should write it as 6.3 for sig figs and scientific notation
Except it should be 6.3 not 6.30 (least number of sig figs in question is 2)
Also for your 7.73, you might want to underline the second 7 to show that quantity is accurate to two significant figures
And -20 should be -20.0 (because of the 1.00 as a distance)
Yeah pretty much (but u could still underline the 7 in the next line as well and change 20 to 20.0)
👍🏻
Thank you so much,icy for your help once more
I will close this channel now
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Sorry
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would it also be right if I did (8C3)(3!)
choose 3 bottles from 8 and they can all be ordered 3! ways
yes that works too
and gives the same answer
(8C3)(3!) = 8P3
which is 8 x 7 x 6
P is permutation btw
ok
but yea u got it
mhmm
d is so trippy
cause if you choose Sony from Reciever, then its 4x4x3
but if you choose sony from disc player, its 5x3x3
oh noo
what am i doing
nononononon
3 slots one for receiver, one for compact, one for speaker
now for speaker neither is sony
so 3 possibilities
now either say receiver is sony
so we have 4 options for compact
or compact iis sony and 5 options for receiver
so 3x(4+5)=27
24 ways, for 1 sony we either have it for receiver or compact, thats 9+12 ways
then for 2 sony we have 3 ways
sure that works too
holyyy im actually getting it?
like actually understanding stuff now
im reviewing the counting and comb and permutations stuff rn
whatttt?
nahhhh
i swear ii was so confused a few days ago
oop
nvm mind
i just messed up on a question😭
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@obtuse totem Has your question been resolved?
i dont know why they split it into two def
they could've just said A and B are independent if ".." or "...."
alright
i think its sleep time
Ive reviewed everything, just wish I had some time to do and redo some questions
if I can do that I'd be more confident
oh welll
thank you all, byeeee
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what
hey u already opened a channel right
idk i did but its gone
its still there
...
i pressed the collapse button...
someone help me close this how do i close this
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ok good
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what have you tried so far?
im not sure what the question is asking me to do haha
is this what the question is asking me to do?
or are there proper way of answering this question?
i dont have the answer for this question unfortunately
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I can't seem to get a picture of this in my head, surely it can't mean for all x in those sets right 
why not
intuitively the condition means that A is on the left and B is on the right of the real number line. so c is exactly the point where they "meet"
Okay I made this diagram from reference
Oh 
I did consider that
Yeah


