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exactly
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help
i have a question
what software do people use to write maths papers
like
research sort of things
where you can quickly type mathematical symbols
like integral sign and stuff
latex
is that an app
overleaf is what people use
oh
overleaf or latex?
search up overleaf
ok
the coding language is latex tho
overleaf is a compiler of latex
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✅
@vital estuary @compact veldt
this is very much giving coding
is this what is usually used?
yes
also do you think i should learn to code this summer
i really enjoy maths but for literally everything i am doing atm the question sheets end with, write a code to test X..
i think you should learn to code anyway
I mean, there are also WYSIWYG editor for latex too but I will say coding is better
you dont really need to code too often
you can import images if you need to
you can also use rich text editor in overleaf. that can help you adjust. You can import the template or write the preamble for your doc once and forget about it
a simple noob example i made with latex
coding for what?
nice
general life
most of these assignments allow any programming language
java for usefulness
python for simpleness
python would be easy language with a lot of tutorial
snakify for learning python
is that free
i think so
okay
I think CS50 is also good one
what is this?
oh that harvard course?
Free Harvard course
basically i am applying to university in october
to study maths
should i spend my time between then and now learning to coe
code
Learning code for mathematicians is beneficial, but not like you have to learn now. Feel free to learn if you want to but you can also learn that in college too
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Hello
How do I know if proj or perp has a shorter distance to point P?
Or do I just calculate both and compare
@hybrid basin Has your question been resolved?
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This is part 1 of a question (and its answer)
This is part 2, which is the part that im stuck on
Im guessing that we ignore everything and just take whats inside the square root (13t/6)
And set it equal to something
But idk what
what is the question asking you?
What do you mean sry
what does the question mean? can you explain it in your own words?
Get the smallest positive max of t
that doesn't sound right, shouldn't this mention d(t)?
what is d(t)
I guess I dont really understand the question
Or what it means by 'distance is maximal' anyways
didn't you just calculate that?
I think it means a local maximum
Ah ok
That was what I thought it meant but I got a bit confused haha
Get the smallest positive value of t where theres a local max?
sounds good to me
you're right that you can ignore the square root and that will save you a lot of time
how would you normally find the value of t where there's a local maximum?
Set it equal to 0 to find where cos = 1?
okay sure you could do that
Yeah?
that's more clever than what I would normally do involving derivatives
how
13t/6 = 0
No
something about cosine
Wym?
you're trying to maximize that function right
yes
you identified that you only needed to maximize that cosine term
and noticed that cosine capped at 1
and cos(u) famously is only 1 exactly when u=0 and nowhere else 😔😔😔
There was a nicer way to say that but i get your point
2pi right?
so t = 12pi/13
It was correct! Thanks 😄
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can i take here
(1000,0100,0010,0001)
I think it might be useful to think of a), b), c) and d) as a certain transformation applied to the list of vectors you were given, so along as these transformations (which seem to be linear) don’t squish down to a dimension or so, then the list is still linearly independent (if I haven’t missed anything)
Or I guess just by observation, can you rewrite any of the vectors in the list from the others?
For d) for example
Let’s call u = a1 + a2, v = a2 + a3, w= a3 - a4 and z = a4 - a1.
Notice that u + z = a4 + a2,
And so adding w, we get that
u+z + w = a2 + a3
But this is just v
So we’ve managed to rewrite one of the vectors in the list in terms of the other
Hence d) does not form a linearly independent set
Try and do something similar for the others
Or possibly view them as transformations if possible
@sinful frigate Has your question been resolved?
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I am confused upon this question
I do know the basics of a sin function and how it works but I am confused about it being in degrees?
wasnt someone literally just asking about this question?
who?
Like I have an idea to go about it
trying to find the maximum or higest point first
But I dont know what that would be since there is nessesairly no limit
What is the maximum value of sin x?
that is odd
No like I mean the maxmium point of intersect
so that I can work backwards from there
Which is why you need to know what the maximum value of sin x is
When does x/2024 equal 1?
what
I was about to get to that but I am glad you got to that yourself
since both equal 0 one is just the phase shift 360 degrees forward
thank you
do you know the period of sin?
No it wants degrees not raidans
then 360 degrees
yeah so its periodic and at one point they will interesect
not at one point
ok so there is more than one points it could intersect
visualize x / 360
ok
and also sin x
yep I graphed it out
So I see the crests and the troughs
at which degree
hold on would I have a common denominator
of x/360 and x /2024
not really
but the 360 will be important
but between interestcting x/360 and sinx its just a line
interestecting a sin function
over the x axis at y = 0
Point is: you will intersect sin x at 2 points if my brain is working correctly
and im not seeing ghosts
would the two points be the same except one set is negative
thats not what I want to get at
ok
Thing is: for x / 360 (x >= 0) you intersect sin x twice
alright makes sense so far
Meaning for x / 720 you would intersect it how many times?
remember that 360 degrees makes one period of sin x
four times
The thing I want you to realize is that once you figured out how many intersections you got for one period you can calculate them for every period by just adding
for x / 1080 you would intersect sin x how many times?
Somewhere we will reach 2024
what we need to realize now is something very important
when do we intersect sin x
ok
Obviously x / 2024 is positive for positive x
yes
thats what I wanted to talk about
sin90 to 180 is not possible
cause those are all negatives
sin 90 is 1 and sin 180 is 0
sorry i meant 180 to 270
close but not completely right
how
180 to 360 is not possible
thats the only part its in the bottom section
oh wait
nvm
cause 270 to 360 is where it uprises again
for a half period we intersect, and for the other half period we do not
yes now I am finally seeing that
cause one period goes from middle to top to middle
so that limits our options
which makes it easy to tell the maximum number of intersections for positive x
too complicated just take a look at what we already have
ok
we know for x / 360 we intersect sin x 2 times
yes
for x / 720 4 times and for x / 1080 6 times
how about x / 1440?
and by extension x / 1800?
ok now for x / 2160?
yes so we overshot it a bit
wait is it because 2024 is in the period with 2160
x is in degrees
wait why?
this would be it
do you know the way to get to this answer
ah yes for it to not intersect two times, the denominator would need to be smaller than a quarter period of sin x if that makes sense.
Visualize x/1889
ok I see it
here we do not intersect the period 1880 < x < 2160 anywhere
ok i see it
thing is, as soon as we look at x/1890 we do
oh yeah
and for anything > 1890 we intersect 2 times
that makes sense
ok
But is it
but some of these interceptions would not make sense
ur still missing the fact that x is in degrees
Depends tbh
cause 90/2024 does equal 450 over 2024
when x is 360 degrees x=pi therefore y=pi/2024 at x=pi
3.14 degrees
radians
If we get x in degrees and we use sin we would also look at sin x in form of degrees no?
idk if what i wrote makes sense
like this
there a way to convert desmos to degrees
Does your exercise specifically state that sin shall only be used for x in radians?
because lets say x=2024 degrees, then sin(x) is not 1, but y=x/2024 if y were in degrees then y=1 which contradicts as y=sin(x) which is not 1
yeah
it still intersects twice though
all it says sinx in degrees and x/2024 in degrees interesct
at what points
cause 0 is one of them
as 0/2024 = sin0
what?
it does 0 is one them and 175.039
is the other one
I don't see the issue ngl
anyways sin(x) is a function that returns radians?
no i made return degrees
sin(x) returns a value between 1 and -1 regardless of input
nvm im dumb but my poiunt still stands
x at 2024 degrees y=sin(2024)=0.72726665034 but y=2024/2024= 1
yea that point makes sense
but both at 175.039
are equal
same with 0
but the problem is quite simple I dont have a formula to calculate 175.039
but sin(2024°) is -0.694658...
sin(2024 rad) is 0.72726665...
right i put it online which auto assumed radians, but none the less thats worse
why is it worse
ok thats not important
because y=x/2024
we got the two points we just need a formula to show so
so your point is that f(x) = sin x = x/2024 is what we are looking at?
because y = sin x and y = x/2024?
correct
yes
yeah I belive those are two different functions
and if x is 0 or 175.039 there are equal
u need their outputs to be in the same units
u cant work y in degrees for 1 and not for the other
rather the y coordinate of a point on the unit circle etc etc i guess its clear what i mean
i dont get how i can explain this to u so u can understand
So your problem is that I am not dividing x/2024 but rather x°/2024
take y=sinx and y=x/2024, for those 2 equations to intersect then sinx=x/2024, but notice that if x is in degrees this doesnt hold true for 99 percent of values
What
I mean yes obviously it doesnt hold true for 99% of the values you could also say for 99.999...% whatever values
The real question is
What happens if I divide something with a unit by something without a unit
what unit is 2024 in
well it still remains in that same unit system
if u divide degrees by any non unit number its still in degrees
360°/4 is still 90°
I hope we are not unnecessarily overcomplicating things here :
we probably are
because how would you plot y if y were in degrees
well it changes the answer by a large amount
y isnt in degrees tho
if i divide x/2024 it is
going by what you just told me
if x and y were both in degrees like u said, then it would look like y=x/2024
which also implies sin x never equals x/2024 because they are in completely different units
where they are both unitless
one has none and the other is in degrees
u can convert degrees to radians
the whole point of radians was to convert degrees to a standard unit of length that we could measure
but it wouldn't change the fact its a unit 
sin(x) give a unitless answer
x/2024 doesnt by your argument
radians are UNITLESS
they arent a proper unit
u can't pull out a radian lenghted ruler
because radians dont have a length
u can convert x so that it is in radians
That would make for a more complicated answer ngl
@unreal ridge is this a university question?
no
the question can be solved at any level
techinically its a course question
if you took grade 11 math you should have the skill set to solve it
The thing I am currently looking at involves some ridiculous values
If I were to transform x to radians with x° * (pi / 180), x / 2024 will only be ~ 1 at x = 115968
which means I have come across ~18456 periods
which means I intersect sin x 9228 times
for positive x
negative is the same amount
so I intersect sin x 18456 times and crossed 36912 periods doing so
if this is the answer I am eating a broom
im getting around 728641 intersections
i got 23 interesections
@unreal ridge Has your question been resolved?
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hi
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Getting a couple different answer from different calculators. Can anyone confirm this is the right answer?
L = lim (ln(z))^(1/(z-e))
ln(L) = lim 1/(z-e) * ln(ln(z)) = lim ln(ln(z)) / (z-e)
that's of the form 0/0 so using l'hopital's you get
ln(L) = lim 1/z * 1/(ln(z)) = 1/e * 1/(ln(e)) = 1/e * 1 = 1/e
then L = e^(1/e)
so that's correct
Thank you I appreciate it.
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!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
I am stuck on part a and b
Using the fundamental theorem of calculus
For part 2
Well for a) they are referring to a theorem you've hopefully seen before.
What does it say?
it just means that whatever f(x) in the integral is the derivative of g(x)
I just dont get how to show the second part
Can you find an antiderivative of 2 + sin(t) then?
that would be 2t - cos(t)
Ok. And then you want to plug the bounds of the integral inside of that right?
yes but its from 0 to x so what do i do ?
You can still plug in x and plug in 0.
so then 2x - cos(x) - 1
Yes, and you now want to differentiate that.
Indeed.
so F' is 2x - cos(x) - 1 or is that just f?
oh wait thats the same thing
so is F = 2x - cos(x) - 1
or is F = 2 + sin(x)
and F' = 2x - cos(x) - 1
g'(x) = 2 + sin(x). The point of the exercise is to use both parts of the theorem see derivatives "undo" integration.
F = 2x - cos(x) - 1 or F = 2 + sin(x) don't matter, since any antiderivative of the form F(t) = 2x - cos(x) + C will work.
2x - cos(x) is AN antiderivative of 2 + sin(x).
2x - cos(x) - 1 is also an antiderivative of 2 + sin(x).
It doesn't matter which one you choose, hence why when you do (or will do) indefinite integrals you'll be asked to add a +C at the end, signifying that any constant does the trick.
I don't know exactly what the two parts of the theorem they're referring to are.
The goal is just to see that $\frac{d}{dx} \int_a^x f(t) dt = f(x)$, whether it's by realizing that $\int_a^x f(t) dt = F(x) - F(a)$, so $\frac{d}{dx} \int_a^x f(t) dt = \frac{d}{dx} (F(x) - F(a)) = F'(x) = f(x)$ \
OR straight away seeing that derivatives undo integration, so $\frac{d}{dx} \int_a^x f(t) dt = f(x)$.
Azyrashacorki
i can show you
oh so F is the anti derivative
and F' is the original function
so the anti derivative is F = 2x-cos(x) - 1 and then F' = 2 + sin(x)
Yes exactly
im having trouble understanding what the purpose of what we just did was
did we just get the derivative of the function?
cause there's another question right after this one that asks to get the derivaitve using part 1 of the fundamental theorem of calculus
$y = \int_{0}^{tan x} e^{-t^2} dt$
wakamole
so how would i do that?
You showed that derivatives undo integration, essentially.
Can you actually show me part 1 rq? Just want to make sure I'm not going in too deep hahah
Azyrashacorki
Can you see that this is just $h(\tan(x))$, where $h(x) = \int_0^{x} e^{-t^2} dt$?
Azyrashacorki
yea
So really it's just a composition of functions. Do you think you can apply the chain rule to it?
$e^{-tan^2x}$ ? to that?
wakamole
We have $h(x) = \int_0^x e^{-t^2} dt$, you want to compute $(h(tan(x))'$.
The chain rule gives $h'(\tan(x)) \cdot (\tan(x))'$ right?
Azyrashacorki
But we know the derivative of tan, and we also know what h' is from Part 1 of the theorem
im not getting it im kind of bad with chain rule
why do we want to apply chain rule?
again?
Well it turns out that the function we're looking for is the derivative of h(tan(x)).
And this function is composed. All that Part 1 says that that $h'(x) = e^{-x^2}$.
Azyrashacorki
ok
The issue is that I don't think this one has a nice antiderivative. And whatever you do, you'll need to use the chain rule at some point.
so we substitute in tan(x) and then subtract 0?
like h(0)?
or is thtt for part 2 only?
That's part 2, and we'd need an antiderivative, which we don't.
oh
yeah
so like cah you shoe me what to do then and i can ask questions
im just not getting it at this point
Yes that's fine.
Not really, it's just a name for the function at the end of the day
So we have $h(x) = \int_0^x e^{-t^2} dt$. Why do we use that? Because that's the only function we have information about from the theorem's first part.
Azyrashacorki
Yep
so then h'(x) = f(x)
but im looking at the answers for the odd questions and they plugged in the top interval to the variable
It will come
Now, the function we actually are after is $(h(\tan x))'$, since $h(\tan x) = \int_0^{\tan x} e^{-t^2}dt$.
Azyrashacorki
So far so good?
yeah so far
Ok, so using the chain rule, we know that $(h(\tan x))' = h'(\tan x) \cdot (\tan x)'$.
Azyrashacorki
yea
But we know that $h'(x) = e^{-x^2}$, so we actually know that $h'(tan(x)) = e^{-\tan^2 x}$.
Azyrashacorki
And then we get this extra factor at the front since $(\tan x) ' = \sec^2 x$.
Azyrashacorki
So at the end of the day, we get $y = (h(\tan x))' = h'(\tan x) \cdot (\tan x)' = e^{-\tan^2 x} \cdot (\sec^2 x)$.
Azyrashacorki
wow
i am getting it
the chain rule applies to so many things
we could also have done it that we just get the derivative of $e^{-tan^2x}$ which is also chain rule ? or is that not the right way to dfo it
wakamole
Hum, you'll notice that if you actually compute the chain rule in there you'll get a -2tan(x) term out front which we don't want.
The reason why this part of the Fundamental Theorem is useful here is that it turns out this function (e^{-x^2})has no antiderivative, at least not in terms of general functions we're used to working with.
So you couldn't even look for an antiderivative in the first place.
oh yeah youre right
is it usually using the chain rule to find the derivative in this form? for these types of questions?
Like for any of these ones?
Yeah it's all the same principle
its confusing becuase for 16 h(x) already has x as the top part
so would this be the quotient rule then?
Well I used h(x), but it could be anything.
You should always try to write it back as a composition of the integral with just x (from part 1) with the upper bound (sqrt(x)).
wait i just read online somewhere that you do h'(x) * d/dx the upper bound
is that a shortcut?
Well it's just this but replace tan(x) with a general function f(x).
oh yeah
that is it
but if the lower bound was x and theupper bound was like 2x youd subtract the lower bound from upper
or is that part 1?
im kinda confused on what part 1 is ... like when does it become part 2
i think i get it though
$\int_{-5}^5 e\ dx$
wakamole
Part 2 requires finding an antivderivative. Notice that part 1 says that the lower bound can be any a. It doesn't change that g'(x) = f(x).
how does this even make sense lol
oh yea thats right you need the antiderivative of upperbound- antiderivative of lower bound then derive that
so thats the same thing as the chain rule?
Yeah it will still be h'(x) * d/dx (upper bound)
oh thats right but if we do that then we arent derivnig at the end
are we?
so wait F(b) is chain rule
and F
is
the derivative of f(x)?
oh wait i mean antiderivative of f(x)
and b is the upper bound
It that's really your integral you should be able to just use part 2 though.
e is just a constant, so yes it's just eb - ea
and you just leave it like that right?
im just a little confused becuasee when we did the very first problem you had me take the antiderivative of f(x) first, then plug in the bounds, subtract F(b) - F(a) and then derive it to get the answer.
but now i feel like we're not getting the antiderivatine of anythng and we're just doing d/dx f(x) * b - d/dx * a, am i right or am i going crazy here lol
It depends what they're asking for.
If they want the derivative, then yes you have to differentiate.
If not then no need.
ooh
ok tham
thanks
wait so is the integtral of this e * (5 - (-5)) ?
i found the answer is that but why not e(5) - e (-5) ?
nevermind i got it... constant so it's c(b-a)
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is the local max and abs max (16,4.8)
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Hey
do it step by step
you do additions and subtractions from left to right
so obv the $210\sqrt{2} - 210\sqrt{2}$ cancels, then for the $\sqrt{3}$ terms, you can group them tgt to get $\sqrt{3} \cdot (35 - \frac{10}{3} + \frac{1}{3})$
PhenomPlasma
but you can reorder $a-b+c=a+c-b$
Element118
i think you just made an arithmetic error tho
or you can do $a-b+c=a-(b-c)$
Element118
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for this can i just do 1/10 = 1/5 + 1/i ? its a concave mirror so can i just do 1/10 - 1/5 and take the inverse to find i?
@plain vessel Has your question been resolved?
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,w integral from 0 to 1 (x-1)/(1+x^2).ln(x)
What
Bro
,w int from 0 to 1 (x-1)dx/[(1+x^2).(ln(x))]
Aaah
,w int from 0 to 1 (x-1)/(x^2+1)*ln(x)
Ok
wolfy was literally high on something
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I graphed both 1/cos(x) and 1/sin(x+(x/2)) on my calculator but they dont coincide (like what the answer shows for cosec (x+x/2) and sec (x)😭
i also dont understand how sin(x+pi/2)=cos(x) I literally can't figure out angle relationships
should the graph be like this
red is sec(x)
blue is cosec(x)
green is [-2π=<x<=2π]
do you know sine addition formula?
⬇️
sin(x+(π/2)) = sin x cos(π/2) + cos x sin(π/2)
sin(π/2) = 1
cos(π/2)= 0
so...
sin(x+(π/2)) = sin x • 0 + cos x • 1 = cos x
@wraith badger
I’m not sure but I got something similar on my calcualtor
Idk why the question shows them like together
OH YES THESE I KNWO THESE
Bro I had no idea we had to use that to figure it out
I SEE NOW
Thank you so much
wc😊
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converting from degrees to radians, do I find the highest common multiple between the degree and 180. e.g 150 degrees pi over 180? What would I do
Degree * pi/180 = radian
150 * pi /180 = 150pi/180 = 15pi/18 = 5pi/6
Well yes, simplify the fraction
Till you cant
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can someone explain how to get from the first line to the second line
Please don't occupy multiple help channels.
they did do that
left them with 2x(2x^2+9x+9)
then factorise the rest of it in whatever way you choose, ac method, quadratic formula etc
whats the ac method
i havent done it in too long so i forgot how to
i thought u just had to find a number that multiplies to 18 and adds up to 9
Why 18?
cuz theres still a 2 in front of the x^2
Lets do this slowly
2x(2x^2+9x+9)
Lets factor inside the parenthesis
2x^2+9x+9 = 2(x^2+9x/2+9/2)
Do you agree?
@hybrid haven
So now we have 4x(x^2+(9/2)x+9/2)
We are gonna factor inside the parenthesis again, now that x^2 has 1 as coefficient
x^2+(9/2)x+9/2 = x^2 + (9/4)x + (9/4)x + 9/4 + 9/4
x^2 + (9/4)x + (9/4)x + 9/4 + 9/4 = x^2 + 2(9/4)x + 18/4
x^2 + 2(9/4)x + 18/4 = x^2+2(9/4)x + 72/16 + 81/16 - 81/16
x^2+2(9/4)x + 72/16 + 81/16 - 81/16 = (x+9/4)^2 - 9/16
(x+9/4)^2 - 9/16 = (x+9/4)^2 - (3/4)^2
(x+9/4)^2 - (3/4)^2 = (x+9/4-3/4)(x+9/4+3/4)
(x+9/4-3/4)(x+9/4+3/4) = (x+6/4)(x+12/4)
(x+6/4)(x+12/4)=(x+3/2)(x+3)
Gathering with the previous the final result is
4x(x+3/2)(x+3)
Which exactly the same as 2x(2x+3)(x+3)
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Hi I need help with this problem
and, what is the question
Idk my professor just told me to solve this with no explanation 😔
He said this is the question
put a bit more effort into your trolling
Idk if my professor is trolling my guy
He is
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Like this
Ok thanks
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help with logic
say P is "throwing an egg at a wall" and Q "the egg explodes"
if I throw the egg and it explodes, P->Q is true
An egg can explode without it being thrown at the wall btw
but when I dont throw an egg, whether it explodes or not, P-> Q is still "true"
so what does it mean when I say its "true"?
But the egg also might not explode when it’s thrown at the wall
true as not proven false?
I like to think of its this way
if I say if 'I have a cat I will name is bob'
if i don't have a cat
I am technically not lieing
hence the statement is till true
I think my issue comes down to what "true" and "false" mean here, because if I didnt do any relevant thing to the argument P -> Q then its odd to say it is "true", its just unknown
if I say "when I buy a pen, it'll grow legs and run away" then until I dont buy a pen, my statement is true?
ok, brought down to math:
0<|x-c|<d -> 0<|f(x)-L|<e
if both are true, the limit exists
if x is within delta of c, but f(x) is not within epsilon of L, the limit does not exist
but now, if x is not within delta of c, then it is meaningless if f(x) is within epsilon of L
I think im confusing "true" with "proven true", I guess I misunderstood that
I read about vacuous truth and I think that sums up my doubts
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binomial probabilities dont use standard deviation right
Binomial random variables have standard deviation.
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Can the similarity of triangles be proved using the cosine rule [which is easy to prove]?
What do you mean with the cosine rule?
Do you want to prove that cos(A) = cos(B) or something?
To prove similarity of 2 triangles using:
What in there do you want to be the same?
Like how would you want to prove it with that?
2 angles are the same?
yes.
because then you can just use soh cah toa?
For all triangles.
this is for right triangles, innit?
I just want to know whether it is possible. I highly doubt it isn't possible.
Oh
Yeah
You could use zhz then?
“If you know two sides and an angle of a triangle, that is actually enough to be able to say that those two triangles are congruent. What is important here is that the included angles are exactly the same size. Then we speak of the congruence characteristic ZHZ for triangles.”
I just want to know that is it possible to prove : that the ratio of sides will be the same.
If two angles are same.
Consequently the third of course.
yh then they will use the lowercase
Given that the angle is between the two equal sides.
the zhz like I said
U mean SAS?
z is side and h is angle?
yes
After you’ve proven that the triangles are similar or congruent, you can say that the angles are the same
ikr, but that's the thing I want to prove.
I might not understand your question…
My conjectures (which the former is proved):
"If two angles of a triangle are equal to the angles of another triangles, consequently the third angle, then the ratio of the corresponding sides will be equal. This can be proved using the cosine law."
For example, in triangle ABC and DEF, if ang A = ang D, ang B = ang E, then AB/DE = BC / EF = AC/DF.
-=-===--==Is the latter part of my conjecture true which is italicised?-==-==-==-=
I think so, because you put the same stuff in it (from the zhz)
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how do i do this if im missing 2 values ?
You're given the definition of X
The way P(X=3) is given, there is a direct implication of the distribution of each of the two spinners
how is P(X=3) calculated, sum of two numbers
so the numbers 1,2 can add to 3 so is that 1/16 + 2/16? im confused
How do you get a sum of 3 using the spinners?
if you spin a 1 and then spin a 2
What does it look like the probability of 1 on first, then 2 on second are?
1/4 and 1/4
So you have 1/4 on every number for both spinners
Then how do you get a sum of 7 with the spinners?
Therefore, the probability is
1/16 if u multiply them im assuming
I think that's an ok assumption
Then you can get the last number by calculating it, or just using 1 - everything else
thanks
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how to tell if these series converge
this is not telescopic series right
so I cannot just check the lim of partial sum
other than that I think I can bring it to common denominator and then multiply by conjugate
@ornate creek hi you need to send your question in one of the unoccupied channels
Like #help-40
integral test maybe
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Starlights Productions is hosting an annual outdoor concert. Average attendance is 40 000
people when tickets are $100. For every $5 increase in ticket price, 1 000 fewer people are
expected to attend the concert. What admission price will produce the most revenue? Explain how this can be
determined. BTW, the quadratic function in standard form is: R(C) = - 5000p^2 + 100,000p + 4000,000. Where R(C) = revenue concern and "p" = number of ticket price increases of $5.00.
who could figure this out as soon as possible pls
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i was wondering how it can be -8/17 if the ratio represents a length
the answer makes sense and i have no issue with solving but i just wanted some clarity on it
<@&286206848099549185>
do you know how the sign of sin cos and tan changes with variation in quadrants
yes
thats how
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Yes
Look at the signs too
which is -3/5
Yes
so i would get (- 3/5)(2A)= 2(-3/5)^2 (A)-1
that feels wrong
am i pluggin in values correctly?
Why did you write A again?
No wait
A is not seperate
It's Cos A =-3/5
cos 2θ = 2cos^2θ-1
Put cos θ in RHS
See A as θ
$2cos^{2}(A)-1=2[cos(A)]^2-1$
77²
oh
whoopsie
lets use that then
2cos^2(A)-1= 2 (-3/5)^2-1
now how do i condense that?
to get a proper answer
cant use a calculator obviously
!occupied
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bruh the options are in fraction
wow
looking goof?
d
-7/25= -0.28
so
unless ive screwed up in a major way
it's just the regional trait
is the thumbs up a yes im wrong or yes im right
You're good
it's alright
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is there a specific way to simplify the numerator?
sus
no like why is it 49x3 instead of some other number like 1x147
the denominator should just be 8, no sqrt
49 is 7^2
you can split sqrt(49*p^4*3)
to sqrt(49*p^4)*sqrt(3)
thats not really my question
I assume it’s to help you
you want to make whats in the sqrt as little as possible
oh
Because the sqrt of 49 is obvious
The sqrt of 147 is not so obvious at first glance
But whoever previously spoke is right
The bottom should not have a square root
wait so why does 147 become 49x3 instead of any other possible two numbers that multiplies to 147
Well
49 is a square number
If you can find any other square numbers that fit into 147 be my guest
ohh
But you’ll end up with the same result, 7 sqrt(3)
thanks i get it now
so whatever number that can multiply in~~ blank~~ numerator should be a perfect square?
@ruby crown Has your question been resolved?
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im hardstuck 2nd question i just dont get how to find the major axis
do i need to use c^2 = b^2 - a^2
i know that b=3
and then what do i do with this chord length of 10
@midnight oar Has your question been resolved?
We're given that the minor axis is 3, so we know that the equation of this parabola is $\frac{x^2}{a^2}+\frac{y^2}{3^2}=1$. Since the chord we're given is length 10 and at height 1.5, we know two more points on the ellipse: (-5, 1.5) and (5, 1.5), we can plug in either of these points for x and y to solve for a.
DonDoesMath
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