#help-10
1 messages · Page 532 of 1
you can't use y=mx+b in this situation.
you can.
I think he means immediately
Well obviously.
Yes, that doesn't mean you cant use it.
Equation of straight line: y = mx+c
now m is 3
x is -7
y is 2
c is unknown
Solve for c then you will have the equation of the line
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x2 +5x +6 >= 0
I got results:
im confused to like
at the end the >= has to flip
she got -3 flipped
and other x>=-2 like normal
oh
It's cuz between -3 and -2, the value is a negative number
So even if the number was -4, it'd overall give a positive result
hmm
Here I put a graph for reference
Cuz u cant get the sqrt of a negative number right?
Do u see how it can be less than -3?
yeah but
i thought it would be a result of inequality
like
i thought you could calculate inequalities
and >= flips when something hapens
The inequality is just another way of writing what she wrong in the pink writing
The U means and
like i just calculated the inequality and like
on test i would just write x >= -3 , x >= -2
im a bit lost
That one doesnt work tbh
Its the right idea buuut
wait
because its a polynomial
i have to conclude that
it has to be like
-3 can be lower or equal
is that the thing?
Yah
but yo
The inequality is the same thing as the (-inf., -3] U [-2, inf.)
Yah this one's a bit easier to explain
U cant divide a number by 0, right?
ye
Basically it's just stating that u cant have x be -3 or -2 cuz that would make it 0 on the bottom
Cuz what u said, the polynomial would end up giving 0
Welp, im gonna head to bed it's really late for me
I wish I could help more thooo
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idk
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Two functions are given by the regulations f (x) = 2x^3−150x and g (x) = x^2 + kx + 25−500, where k is a constant. The function f has a local maximum at the same point as g has a local minimum. Based on this information, determine the value of k.
I tried to find k, by differentiating f(x), g(x) -> f'(x), g'(x)
then finding an expression for x1,2 from: f'(x1) = 0, g'(x2) = 0
and solving the equation x1 = x2 to find k
but I couldnt get it right
who can help?
<@&286206848099549185>
show your work and someone can review it
take pictures w/ phone or something
yeah ok gimme a minute
use an app to downsize it too
how do you know you couldn't get it right
is there like an answer key
or answer choice list
ok so i don't take calc but i think i have an idea
So your idea of differentiating f(x) and g(x) is what I'm thinking of
and you know that the critical points of a function are when the derivatives are equal to 0 right
so taking the derivatives of your functions you get
f'(x) = 6x^2-150
g'(x) = 2x+k
So setting f'(x) = 0 we get 6x^2-150 = 0 so x = +/- 5 right
So if we plug in a value such as -6, we see that f'(x) will be > 0 so it will be increasing up until x=-5 so that means x=-5 is a local maximum...I think
So then plugging in x = -5 to g'(x)
We get 2(-5) + k = 0...so k must be 10 I think...?
This might be completely wrong idk
it might be k=-10
hm
that's weird though
because wouldn't both of those be a local min...
so it can't be k=-10
no what the hell it has to be k=10...am i stupid...?
i don't understand...
what am i doing wrong wtf
@lusty vigil do you see the error in my ways lmao
Ok let's review...
g(x) = x^2+kx+25-500 has a local minimum at
x = -b/2a
x = -k/2
We're given
f (x) = 2x^3−150x
the local maximum of f is the same as the local min of g
local max of f is x =- 5.
-5 = -k/2
-10 = -k
k = 10...?
wtf am i doing wrong
the points are different but they have the same x values...but i don't know what else I'm missing...?
ugh
pain.
someone else more qualified please ping me when you see what i did wrong lmao
@lusty vigil Has your question been resolved?
@hasty plinth
I looked
at it
and
seems better than what i did
but anybody qualified?
@lusty vigil Has your question been resolved?
@lusty vigil Has your question been resolved?
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I just need help with part a)
@wanton dagger Has your question been resolved?
<@&286206848099549185>
Did you attempt anything?
I found the inverse of them
So for a, what's the inverse function?
Y=x-7
Do you know what $f^{-1}[f(x)]$ means?
Nope I’m confused on that
Do you know what composite functions are?
Yes
Oh ok
Have you seen (f o g)(x) before?
That is a different notation for composite function
Ohh ok
So for instance, y = 5x, the inverse is y = (1/5)x, f^(-1)[f(x)] means plug in the function f(x) into f^-1
When I say something like f(3) = 3x - 4, do you know how to interpret that?
Yh 3(3)-4
That's the same concept of f^(-1)(f(x))
For my example, f(x) = 5x and f^(-1)(x) = (1/5)x
As you mentioned, f(5) means plug in 5 for x, in the function f
So same idea for f^(-1)[f(x)], it means plug in f(x) for x in the function f^(-1)
So 1/5(-1)
Ok I’m confused in the notation
Here watch this
https://youtu.be/uiMNvOPqrSM?t=345
An introductory video to composite and inverse functions.
Support the channel: https://www.youtube.com/channel/UCf89Gd0FuNUdWv8FlSS7lqQ/join
Practice Problems:
functions - http://bit.ly/2PLrRnn
solutions - http://bit.ly/35mipO2
_____________________________________...
About 5 minute watch starting from the location I linked it at
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May I get help with this, I am completely lost lol, prefferably a step by step help
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Hello! I'm having trouble with understanding how to use the half-angle formulas (particularly if the formula should be negative or positive). The question states: cos(x)=-4/5, 180 degrees < x < 270 degrees
I've worked it out and it seems to me that sin(x/2) should be negative, but other sources say otherwise without much explanation
Because since x is in quadrant 3, both sin and cos should be negative
@stiff maple Has your question been resolved?
<@&286206848099549185>
Other sources are wrong
So the answer here is right?
@tardy epoch are you sure?
Because if both sine and cosine are negative, that would make tangent positive
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The sum of the first 10 terms of a geometric series with a common ratio of –1 is 0. What is the first term?
I got 0, but this is multiple choice and that's not one of the answers
hi
ping me when you are ready
@deft nimbus hello! sorry ready for what?
ok you got the answer choices?
4, -4, 1
those are the choices?
mhm!
hm
right yes I'd assume so? Idk how to get those though
right
so the number itself should alternate between it positive and negitive forms
lets get 4 for example
so the first term is 4
next 9 terms would be
+4,-4,+4,-4,+4,-4,+4,-4,+4,-4
right?
mhm
0
but then aren't all numbers possible?
it would work with any number
yes all numbers are posible
but since those are the answer choices they give you
ohhh
you would choose all of them
but
that only works for even terms
not odd
if it was 11 terms it would not add up to 0
is that it?
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have a great day
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how would you do this?
Which question?
i need for number 61
Ok what have u tried?
well since i got stuck on part a i did substitution for part b
i got 1/2* [1/(x^2+3)]0,-2
however
i dont know how they got 3, 7
When ur substituting u
U have to substitute the limits as well
Ex when $x=0$
$u=x^2+3$
Plug in x and u will get it
Glory
By finding the indefinite integral first?
how would you do that with this one?
Same method
Substitution
But ur doing it separately
Ur treating it as if ur disregarding the limits
so you just substitute again??
isnt that the same as part 2?
wait wont that get you a different answer since the equation is the same but the limits are different?
Won't bc for part two pay attention to 4th line where the u wasn't swapped out
so how do they get 4/21?
Np
.close
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I need help with this math problem thats due in 2 hours
and this one too if that's okay
I was sick for a week, I told my teacher but he refuses to give me more time to finish this or explain how to do it
@marsh trail Has your question been resolved?
<@&286206848099549185>
@marsh trail Has your question been resolved?
@marsh trail Has your question been resolved?
well first, you need to know how your teacher defines bisector and altitude
euclidean geometry is a fucking PAIN
my teacher personally made us write everything in the form of conditionals which made a single proof a page long...which isn't much in comparison to more complex proofs but considering how many problems he gave us it was a lot
first you state your givens
then you use the definition of your givens to derive something
(in english)
then you write that derivation in english
so 1 goes to 1
2 goes to 3
4 goes to 5
6 goes to 6...?
and then 8 goes to 8...?
that's probably wrong but
yeah
you need to know how your teacher defined each term as he should've gone over it in class
get notes from a classmate
these proofs are always so dumb because teachers always nitpick every little thing to ingrain the definitions into your head
its probably too late anyways rip
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given: S is the area in the first quadrant within the circle x^2+y^2 ≤ a^2
and under the line y =sqrt(3)x
where a ∈ R
how do i find the borders of Theta
or how do I find the angle itself?
nvm i found it
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is it possible to prove that the vertical line is perpendicular WITHOUT using pythagoras' theorem? i think i need to prove that it is perpendicular so that i can then prove that pythagoras' theorem can be used on it
You can use trigonometry to prove it?
we havent learnt trigonometry yet so idk if thats how i should solve it
generally if the angle formed between two lines is 90degs then its a right angle, thus perpendicular/orthogonal with respect to something else
Nvm then
i dont know if we are allowed to assume this, is there any other way to prove it apart from this or using trigonometry?
because if not then i guess i have to assume it then
You're tryna show that the line segment of length one not on the x-axis is perpendicular to the x axis?
So you don't know your trig ratios?
Like sin, cos, tan
"sohcahtoa"
no?
our school program starts trig a bit after this, i have a bit of understanding of soh cah toa, but it hasnt been properly taught
i just know a bit from watching videos online, etc
hm okay how about using cartesian geometry?
ok sure lets try that
hm just thinking about it don't think you can do it with cartesian geo
Since i was thinking to show that
But since the y-axis has a gradient of 0? idk to word this
wait y'kno you just do your things
?
do you think it would be fine if i just assume that its a 90 degree angle?
this is just a high school topic test
Yes it is orthogonal
ok
ah ok
Hm but if we set the vertices are coordinates
we can say that, that vertical line formed
is perpendicular to the x-axis
Because we can see that the coordinates are collinear
and the y-axis goes up/down in increments of integers
no
uh
ye ig all you have to say that the points are collinear
or something
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hi can i please get help
im struggling to find v
i intergrated but it seems to be wrong
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I need help with finding the volume of this shape.
I’m having trouble with finding the area of the front shape
Can you find the area of the front if there was no hole?
Yes
And can you find the area of the hole? Its a semi circle
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why does this limit equal infinity, ignore first equal sign
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if\ $$tan(x)=2$$\ what\ is\ $$sin(2x)$$?
$$\frac{sin(x)}{cos(x)} =2;\ 2cos(x)\ =\ sin(x)$$
AuHasard
how do i proceed from here
$$\left( 2cos(x)-sin(x)\right)^{2} =(2cos(x)-sin(x))(2cos(x)-sin(x))\ =\ 0$$
AuHasard
i dont know haha
hmm
2cos(x) = sin(x)
if i multiply by 2 on both sides
nah
i know what it is
2sinxcosx
but we have sin x on the right
so what are you trying to tell me
i didnt know that
??
what was literally anything you were saying then?
$$sin(2x)=2sin(x)cos(x)$$
$$\frac{sin(2x)}{sin(x)} =\frac{1}{sin(x)} \times 2sin(x)cos(x)$$
$$
can you chill
mate
sin(2x)/sin(x) = 2cos(x)
right?
yes.
provided x != n*pi blahblahblah
ok so we have 2cos(x) = sin(x)
and we know that sin(2x) = 2sin(x)cos(x)
so 2cos(x) is basically just 2sin(x)cos(x)/sin(x)
what then?
let me check what you wrote
yes
$2sinxcosx=(sin(x))(2cos(x))=sin(2x)$
AuHasard
yes?
i would've if it was that easy
here let me show you the alternatives
”what's sin (2x)”
@rocky cosmos if you had y=3x and I asked you what y was when x=2, would you be able to do that?
yes
Ok, what would it be, and why?
y would be 6 because the value of the function is 6 at x = 2
yes
so If I had $\sin(2x)=2\sin(x)\cos(x)$ and I asked you what it became when $\sin(x)=2\cos(x)$
Mosh
you should be able to do this on the back of what you just said.
I disagree that it'd be easier
I don't know tbh
and I feel bad
I've studied trig identities for a while
so 3x=2?
no, x is 2
yeah but you just said cause of the value
Cause you're failing to recognize that this problem too is just a substitution
$2sinxcosx=(sin(x))(2cos(x))=sin(2x)$
AuHasard
No
nobody said if this was wrong
Yeah, cause it's not
it's just pointless
$\sin(2x)=2\sin(x)\cos(x)=2(2\cos(x))\cos(x)$
Mosh
cause sin(x)=2cos(x)
can we treat them as variables?
yeah?
no i mean the trig functions
NO
That is the assumption tan(x)=2
okay type it out
$a=sin(2x)=2\sin \left( x\right) \cos \left( x\right) =\sin \left( x\right) (2\cos \left( x\right) )=bc$
AuHasard
hmm
okay so sin(x) = 2cos(x)
yes
$b=\sin \left( x\right) \wedge c=2\cos \left( x\right) \Longrightarrow b=c\Longrightarrow \sin \left( x\right) \times \sin \left( x\right) =\sin^{2} \left( x\right)$
AuHasard
So $\sin \left(2x\right) =\sin^{2} \left( x\right)$
AuHasard
okay so which one of these are our answer
lol
what lol?
$\tan^2(x)+1=\sec^2(x)$
Mosh
$\sin \left( 2x\right) =1-\cos^{2} \left( x\right)$
i've not worked with sec yet, only tan cos and sin
so should i post the last equation?
sure
$\sin \left( 2x\right) =1-\cos^{2} \left( x\right)$
AuHasard
AuHasard
and solve for x?
Rule of Thumb: You never need to find x explicitly in these problems.
for reference, this is also wrong
they wanted to know what sin(2x) was, so true, not x per se
maybe i should've left it like this
and cause finding x explicitly is just a shit method 
$\sin^2(x)+\cos^2(x)=1\overset{\sin(x)=2\cos(x)}{\implies}4\cos^2(x)+\cos^2(x)=1$
Mosh
didnt sqrt properly.
no
I mean you just didnt square root properly
$x^2=a\implies x=\pm\sqrt{a}$.
Mosh
k.
$$5\cos^{2} \left( x\right) =1$$
$$\cos^{2} \left( x\right) =\frac{1}{5}$$
AuHasard
yes.
aaaand we are still not done
its one more step...
hold on
$$1-\sin^{2} \left( x\right) =\frac{1}{5}$$
$$1-\frac{1}{5} =\sin^{2} \left( x\right)$$
$$\sin \left( 2x\right) =\sin^{2} \left( x\right)$$
$$\sin \left( 2x\right) =\frac{4}{5}$$
sure
though you had 1-cos^2(x)=1-1/5 available to you, but I guess we can't avoid pointless symbol pushing
AuHasard
lol
it helps if i write it all down
memorization i guess
thanks for the help
.close
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@wind bluff Has your question been resolved?
<@&286206848099549185>
<@&286206848099549185>
@wind bluff Has your question been resolved?
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Can someone explain this to me
You pick a door. There's a 1/3 chance you're correct and a 2/3 chance you're wrong.
That doesn't change by showing you a door with a nothing behind it, you knew one of the other doors had nothing behind it. All this does is show you which door to switch to if you choose to switch.
It's called a "paradox" because many people intuitively don't think it could possibly make a difference whether you switch doors or not, after all, aren't they all equally likely to have the prize? To help with the intuition regarding why it could make a difference, suppose that instead of 3 doors there are one million doors. You choose one, then the host reveals 999,998 empty doors. There are only two remaining that haven't been open. Which one do you think is more likely to contain the prize? Yours or the other one that the host didn't open?
@lapis smelt On that, you don't know whether to switch or not. They could have chosen to reveal a door only when you're right, and then switching never works.
The proper statement is that the host always reveals a door with nothing behind it.
Just seeing the host reveal a door once doesn't tell you the host's strategy.
If they always reveal a door with nothing behind it regardless of what you picked, then you have a 2/3 chance of winning by switching.
I don’t understand still. If you chose one out of the 2 doors that are not revealed. Why is it favorable to switch? When the third one was revealed empty?
Because you have a 1/3 chance of getting it the first time and a 2/3 chance of not getting it.
yes, you know there is 2/3 probability that it's behind one of the doors you did not choose. the host is helping you by ruling out one of those unchosen doors, so now you know that the other unchosen door has 2/3 probability to have the prize
If you switch, you lose 1/3 of the time (when your first guess was right) and win 2/3 of the time (when you didn't pick right first time).
There is 1 way to pick correctly on your first guess and 2 ways to pick wrongly. 1 way will make switching fail and 2 ways will make switching work.
That's why it's 2/3 chance of winning if the host always reveals a door.
Now I understand thank you
No problem.
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How can I determine its conv/div ergence?
By which test?
Navix
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$cos^4(at)$
Zoro
can someone help me expand this?
the answer i get using two power reduction methods is not the same as what my prof got
and ive been at it for a while and i still keep getting the same answer i got
what i get is 3/8 + 1/2cos(2at) + 1/8cos(4at)
but im supposed to have 5/16 + 5/8cos(2at) + 1/16cos(4at)
what did you do?
so i first expanded it to: [1/2 + 1/2cos(2at)]^2
squared this expression
then got 1/4 + 1/2cos(2at) + 1/4cos^2(2at)
then expanded the cos^2 again
and got?
3/8 + 1/2cos(2at) + 1/8cos(4at)
,w expand 1/4(1/2+1/2cos(4at))^2
how come there is a square to that expression?
im honestly not sure if my prof made a mistake
or if i keep making the same mistake that doesnt make our answers match up
yeah, Seems like they made a mistake
,w cos^4(at) = 3/8 + 1/2cos(2at) + 1/8cos(4at)
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i need some help with differential forms, could someone check what step is wrong here?
I know the last one is wrong because it doesnt hold $$\varphi^* (d \sigma)=d(\varphi^*\sigma)$$
Enoo58
Mb
Under 2
did i do the wedge product wrong?
x_2 sin(x_2) not x_2
Just you forgot sin(x_2)
in the last term right?
Yeah the coefficient or the second term of the right hand side under 2
I calculated φ*σ and I got
$cos(x_{3}x_{4})dx_{1}Λdx_{2}Λdx_{4}-x_{2}sin(x_{2})(x_{4}dx_{1}Λdx_{2}Λdx_{3}+x_{3}dx_{1}Λdx_{2}Λdx_{4})$
Cogwheels of the mind
So you are right
how do the $x_3,x_4$ get there in the last term?
Enoo58
I got same d(φ*σ) with you
Just the Jacobi matrix is $\begin{pmatrix}1&0&0&0\0&1&0&0\0&0&x_{4}&x_{3}\0&0&0&1\end{pmatrix}$
Cogwheels of the mind
They appear in the third row
ah i see
yeah but still we should have this equality
$$\varphi^* (d \sigma)=d(\varphi^*\sigma)$$
Enoo58
alright i think im having trouble with properly using $\varphi^*$
Enoo58
i thougt i just have to exchange the coordinates
No it’s
$ω=f(y_{1},…,y_{n})dy_{j_{1}}Λ…Λdy_{j_{r}}$, then $φ*ω=\sum_{i_{1},…,i_{r}} f(φ(x_{1},…,x_{n}))\frac{\partial (y_{j_{1}},…,y_{j_{r}})}{\partial (x_{i_{1}},…,x_{i_{r}})} dx_{i_{1}}Λ…Λdx_{i_{r}}$
ah so you calculated the jacobian to get the $\frac{\partial (y{j{1}},…,y{j{r}})}{\partial (x{i{1}},…,x{i{r}})}$ term
Yeah jacobian term
and only of those where we have the corresponding $dx_n$ term right?
Enoo58
Idk, just calculate by definition
for example here the ferst term uses derivatives $x_1,x_2,x_4$ but they are all 1 so nothing happens
Enoo58
Just the first and second the fourth rows and choose three columns
Calculate the determinant
Only none zero terms are we choose columns 1,2,4 or columns 1,2,3
alright got it
thank you very much
do you know a source where i can read more about it ?
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Hey can someone help me?
It’s a quadratic function of 6^|x|
Yeah then you just solve it for different cases, a<0,0<=a<1,a>=1
And thats all?
Yeah
Ok thank you
But how to solve equation for this cases?
the teacher didn't teach us that
I dont know how
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yo yo
ok so this probably shouldnt be too long
i have x^3 - 1 = f(x)
or f(x) = x^3 - 1
and i need to find the complex zeros of it
i tried using synthetic division
and got (x-1)(x^2 - 1)
well you can already say x=1 is a solution
and to do that i gotta get like
factor it down
however
whenever i turned it into (x-1)(x^2 -1)
Whenever you are solving an equation for complex zeros, you can always set x=a+bi
oh yeah I think u did that wrong
how so
x^3 + 2x -1 -x^2 -x -1
I'm getting x^3-x^2+x^2-x+x-1
wh
?
wait no that makes sense
wait but then
where does the x-1 thing work at the end
it should be -2 right
and even then, factoring out again gives us not x^3 -1
I think you're doing something wrong
ok then lets back up a bit
thats how u expand things?
how did you get that from x^3 - 1
im expanding (x-1)(x^2+x+1)
so then how did we get that?
you could use polynomial division by x-1
this i mean
i used synthetic division
and i got (x-1)(x^2 -x -1)
._.
ok so basically
I just did it the old way
you take like all the numbers
and put it on a thing
and then like multiple and add and stuff
its weird but it works but i guess not this time lol
no no i think u probs tried to subtract (x-1), but forgot that the minus carries to the -1
which means u subtracted 1 instead of adding 1
that was very badly said
yeah just redo it but make sure you don't make any silly sign mistakes
ok
if i do it correctly i should get x^3 -1 if i factor it back out right
cus i feel like (x-1)(x^2 -x -1) should become x^3 -1 right
due to synthetic division
ok it turned into x^3 - x^2 +2x +1
but that doesnt work since the intercept is supposed to be -1
(x-1)(x^2 - x - 1)
= x(x^2 - x - 1) - 1(x^2 - x - 1)
= x^3 - x^2 - x - x^2 + x +1
=x^3 - 2x^2 + 1
ok
(x-1)(x^2 + x + 1)
= x(x^2 + x + 1) - 1(x^2 + x + 1)
= x^3 + x^2 + x - x^2 - x - 1
= x^3 - 1
oh!!! so i did mess up on the whole synthetic division stuff
yeah
anyway
so now complex numbers (yay)
so basically just solve x-1=0 and x^2+x+1=0 and ur done
yeah complext numbers shouldnt be too hard
obv 1 is a zero, then
wait actually
x^2 +x + 1
ok so i need to use the quadratic formula
ye
x = -1 +- square root of 1 - 4
over 2
-1/2 + or - 3i?
not sure if thats right lol
wait
it stays in root
$\frac{-1\pm\sqrt{3}i}{2}$
LTHMath
fixed it
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So I have a relatively practical problem and I would like to get some advice on how to approach this problem, as I lack the skill/experience to properly formulate it.
I want to form a Catmull-Rom like spline-curve based on 4 quaternions (expressing rotations from a fixed axis) using spherical interpolation, such that the resulting curve is closed and lies fully on the surface of a unit sphere. I can do this in a practical sense, but I dont know how I could find a formula for that curve, if that is even possible.
Now given an arbitrary but fixed point on the sphere I want to find the closest point to the given point on that curve.
Does anyone have an idea how I should approach this problem? I had no luck searching for answers anywhere so far...
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I am trying to interpret dU/dS(inf, v, t)=1
These are the conditions being specified for pricing an option in a market
I am unsure on how to interpret the infty here. U is the value of the option contract
And my interpretation is that this is saying for any value S, the change in the value of the options contract wrt S is 1. That is, they change at the same rate.
The other interpretation is that as the price of the underlying stock S approaches infinity, the value of the option itself changes closer and closer to the change in S itself
Now that I have typed it out
I understand haha
That is it
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Prove that if a and b are different integers, then there exist infinitely many positive integers n such that a+n and b+n are relatively prime
I tried let d= gcd(a+n, b+n) . WTS d=1. Had difficulty in setting n in terms of a and b
We assume a<b.you just consider prime numbers p greater than b-a
For such p, let n=p-a
Then a+n=p, b+n=p+b-a
They are coprime
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If C divides A and B then it also must divide the difference A-B
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Can the sides and the perimeter of a triangle be an arithmetic progression
I do not think so.
?
Nothing
Bruh.
Why cant it be
What the hell am I doing here?
Someone will help you, do not interrupt other's channel.
But does it have to be the next term of AP?
That doesn't matter, these are general terms.
Besides if we say, d>0
Then it must be the next term.
If d<0 then it should be the first term.
Let’s say sides are:4,6,8, P =18
Sure.
In this case P is the eighth term of the progression
Oh you mean 18 is some term in the AP somewhere later on.
Got it.
That is correct, I thought you meant they should be consecutive terms.
Of course it is possible like that.
You already have the example.
The answer in my book says that it is impossible
I guess they mean consecutive terms
They are not.
Why?
4,6,8,18 being in AP in itself suggests that
6-4=8-6=18-8 which is not true.
Yeah, they aren’t in that order
Yes, if they exclusively ask that they can be any term in some AP then and only then you'd give your example.
Otherwise, what I said remains.
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Hi, could someone let me know if I have completed 5a right?
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,rotate
what are you asking here?
wtf does this question mean
i got exam tommorow, please stay on and help me fast
i got tons to revise
@civic zealot wtf is this question saying
maximum of what
If you take x from the domain of that expression, then it has a maximum output, what is that maximum output?
what does that mean
well square root cnt be negative
so x has to be 0
oh yeah so negative 104
if x=0 then you have root(-3)
right. since you're multiplying by -4, the larger that term in parenthese is, the more negative the expression
so the maximum value is when $(\sqrt{x-3}+26)$ is at a minimum. or, in other words, when $x=3$
Zybikron
what is the inverse of y=mx+2?
x = my + 2
x - 2 = my
y = x-2/m
y = x/m - 2/m
where m < 0
im confiued
@civic zealot elp
help
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@civic zealot what is the inequality about
if m<0, what do you know about a=1/m?
oh
is it that simple
bruh
i done that first
stupid questions
@civic zealot i think like some sort of m sign change lol
like i thought after we do this, m sign changes opposite xd
nope, you know the sign of m, so you can find the sign of a and b
for 15, b is in the domain, so 5-b is in the range. So you need a bracket
@civic zealot we substitue in right
yeah
is square bracket because we are using b in the domain with square bracket right @civic zealot
yeah
how do we know
square bracket means that the end point is included in the interval
parenthesis means the endpoint is excluded from the interval
yes, if a<b, the 5-b<5-a
plug in some numbers to convince yourself it's true
hmm
@civic zealot SINCE a < b, we write 5-b first because it is a smaller number one?
b is the larger number, so when we subtract it we are removing a larger number
which results in a smaller number, yes
@civic zealot would it be correct
othe way around
with same circle and square
?
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✅
What do you mean?
Do you mean if [5-a,5-b) would be correct?
That wouldn’t be correct
a<b is what’s stated
If b is the larger number, when it’s subtracted from 5, it should become the smallest number
If a is the smallest number, when it’s subtracted from 5, it should become the largest number
Thus, [5-b,5-a)
@stoic anchor
Idk if I answered ur question
Think of it like this
Let’s substitute a=3 and b=4
3<4
