#geometry-and-trigonometry

1 messages Ā· Page 137 of 1

halcyon wave
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Can someone explain the ambiguous caseto me

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@silent plank

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I know everything about this unit BUT the ambiguous case 😭

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i was out the day it was taught and i watched my teacher's video lesson and it made no sense

silent plank
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You shouldn't ping specific people without their permission

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$\textbf{ambiguity of the sine rule / law of sines:}$ \
there are two solutions to
$$\sin(k) = c$$
where $0<c<1$ \
for $0 < k < 180\deg$ or $0 < k < \pi$

somber coyoteBOT
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ραμOmeganato5

halcyon wave
halcyon wave
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I'll show the way it was taught to me one sec I'll send

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The only thing im struggling with is how to know if there is a second triangle

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and the way my teacher explained it as shown here kind of makes no sense because when I tried that way on another question I got it wrong

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so I don't really get it

silent plank
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firstly do you understand that there are two angles
that when sin is applied will give you the ratio

halcyon wave
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yes I understand that

silent plank
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ok then the part after that is checking whether its possible for the angles of the triangle to sum to 180°

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in that above example, the sum exceeds 180° (the angle sum of a triangle) so that isn't possible

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so B can't be 148.5°

halcyon wave
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yeah but then on other questions i do that strategy and it says it's wrong

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and then a different strategy is shown

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like for this one my teacher for some reason did 180-C+A instead of 180-B+A like they did before

silent plank
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use whatever angle(s) you have

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what you know about a,b,c,A,B,C are different in every question.
they're just variables.
some questions won't even use those letters

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180-B was in the previous question because B was the unknown angle when applying sine rule

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180-C was used in this question because C is the unknown angle when applying the sine rule

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same strat

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whos saying its wrong

halcyon wave
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oh

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ok thanks

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dang that actually helped a lot i was tryna figure this out for 3 days 😭

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thank you deadass bro

stoic field
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Yo I have a small terminological question regarding geometry. If I have a hypershape that consists of the cross product of a hypercube and a simplex of some dimension, would this be considered a "hyper prism"? Since a classical 3d prism is the crossproduct of a 1D cube and a 2D simplex so to say, but I've found some definition of "hyper prism" online that doesn't seem to match my shape

silver jolt
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i would call it a polytope

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a duoprism most likely

stoic field
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I see, thanks :)

quaint chasm
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this is probably obvious but are there equivalents to pythagorean triples in higher dimensions?

like a sum a²+b²+c²…. = z²

such that all a,b,c… z are integers

i would also assume its not possible for an exponent above 2 since fermat’s last theorem, but maybe it works differently in higher dimensions?

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oh wait ig there’s the trivial case of 1 for all axes

quaint chasm
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thanks

exotic yarrow
full light
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If sin(-x)= -sinx , what is tan(-x)=????

agile saddle
dusky jacinth
agile saddle
tiny acorn
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Like

modest mulch
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geometry dash

tiny acorn
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Using tan x = sin x/cos x

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And the even or odd properties

trim stump
hard ore
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am i on the right way and how do i solve 1-64/49

exotic yarrow
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$(-8/7)^2=64/49$, not $-64/49$.

somber coyoteBOT
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Civil Service Pigeon

exotic yarrow
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negative times negative is positive

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I stopped reading there

hard ore
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thanks

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atleast something

honest pumice
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anyone familiar with geogebra? i need to graph (rcosO,rsinO) = (x,y) for 2 <= r <= 3 and pi/4 <= O <= 3pi/8 in the xy place but the most i was able to get was something like

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i THINK it looks like a rectangle but 1% of my head thinks it can be a parallelogram

exotic yarrow
honest pumice
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whoa

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<@&268886789983436800>

spare ibex
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I graduated chat

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Still a grade level ahead (still in honors i didn't get demoted ⭐ )

marsh marlin
next helm
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why dont we use tau instead of pi

grave pond
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Tradition.

spare ibex
cerulean blade
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@cerulean merlin

cerulean merlin
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@rigid crescent

light pumice
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Can someone help me with a trig question?

lime crownBOT
tiny acorn
lime crownBOT
# light pumice Can someone help me with a trig question?

Asking the actual question right away is more likely to get responses.

Asking "Can I ask...?" or "Does anyone know about...?" doesn't give people enough information to decide whether they can help, and answering can feel like a promise to help with the actual question, which they might find themselves unable to.

covert sun
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Hey

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Any short trick for trigo proof?

silent plank
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what sort of trig proof

covert sun
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For these kinda questions

silent plank
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,rcw

somber coyoteBOT
covert sun
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I asked short tricks to know what to do to make these easy

silent plank
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maybe express stuff in terms of sine and cos first

covert sun
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Yeah

exotic chasm
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btw should we make trig id short notations\
unclear values:\
$\sin(x) = s\
\cos(x) = c\
(\sin(mx))^n=s_m^n\
(\cos(mx))^n=c_m^n\$
clear values \
$\sin(k)=S_k\$
you can use t for tangents

somber coyoteBOT
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tsuitachi (tuitati)

exotic chasm
tiny acorn
exotic chasm
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1/t, 1/c, 1/s

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unfortunately this only caters sin cos tan

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oh, special for reciprocals: write as power form, but for -1 power, you can just write -

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$\csc(x) = s^-$

somber coyoteBOT
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tsuitachi (tuitati)

exotic chasm
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no. 30 can be written as the\ nonformal trigonometric identity notation\
$\frac{t}{1-t^-}+ \frac{t^-}{1-t} =1+ t+ t^-$

somber coyoteBOT
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tsuitachi (tuitati)

gritty tree
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sin cos tan

vague plover
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<@&268886789983436800>

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it’s in every channel with image perms

tiny acorn
dawn creek
exotic yarrow
# dawn creek

In the future, please show what you've done so far when asking for help along with any other relevant context — it gives us more to work with and saves time from explaining things unnecessarily. \

I think it would help to substitute $u=x+y$. This gives $y=u-x$ and $2x+y=x+u$. Then,
$$\sin(x+u)-2\sin(u-x)=0.$$
What do you get when you expand this using the addition/subtraction identities?

somber coyoteBOT
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Civil Service Pigeon

dawn creek
trim stump
wheat wing
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How can i draw here the shape i want to discuss about?

tiny acorn
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If you just want to sketch then any online whiteboard/paint clone is fine tho

wheat wing
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its like i draw there later take screenshoot of it then post here?

wheat wing
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okay

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you know what i didnt like this geogebra stuff

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let me use paint

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the shape is this

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AB being the diameter and the small circle inside is tangent to bigger circle

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the given equation is in the image: 1/r = 1/a + 1/c

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does anyone know this theorems name?

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How to browse for stuff like this by the way cat_thonk

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@tiny acorn any idea?

normal rapids
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so like forgive me

wheat wing
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moyenne harmonique huh

normal rapids
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i didnt see the pic

wheat wing
normal rapids
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thats so tension and stuff not this

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its not it

wheat wing
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well okay

normal rapids
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i mean

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you can find

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names

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of

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stuff

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there

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catch my drift?

wheat wing
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yeah i understood but

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i mean how can i find them easily

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looking in math textbooks would take hours

normal rapids
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ur right

wheat wing
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i also saw this in a math textbook but there is no name given for this theorem

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i have found a video regarding to this theorem

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@normal rapids How do they teach mathematics in france?

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with the proof and reasoning backed or just formulas?

normal rapids
normal rapids
wheat wing
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hmm

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in turkey we get properties -> formula -> problem -> solution

normal rapids
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i think most of the time we get an exemple then we must find ourselves the theoreme(if one) then they give us a the formulas then how we could use those formulas

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not to be detailed...

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um yeah and then they give how to get to that formula...and then what you could get from it

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theres prob words for what im stating but cant think of any...

normal rapids
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mmh

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ig

wheat wing
lone yew
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a building lies at (3, 8)
a transformer lies at (0, 4)
each unit is 10 meters
the building is elevated 15 meters above the transformer

what is the minimum length of a cable connecting the two? (round)

this was from an extra worksheet, friend and i both answered 33.5 but im pretty sure we're wrong but he says we're correct (i think its 52)

we both made right triangles thinking the representation was like a picture and from 2d facing forward.
both intially thought "hey thats a 3-4-5 right triangle HOW are we gonna put the 1.5 in there" but we substituted the vertical (4) and did some pythagorean theorem.
i'm now reconsidering if we were supposed to first take the 5 from the hypotenuse and treat the graph like a top-down map or something and then apply pythagorean theorem with 5 and 1.5 to get around 5.2 as if it was now a 3d projection

exotic yarrow
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but this completely ignores the y coordinates

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I'm with you that it should be around 52

lone yew
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exactly

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hes on some "it doesnt matter now we turned it in"

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sacrificed a portion of my grade for this

exotic chasm
slim plinth
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Ik 30-60-90

rustic crater
exotic chasm
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btw is the double angle property only happens at a circle and not other conic sections?

exotic yarrow
rustic crater
minor heron
# slim plinth

am i tweaking i swear none of the answer options are right šŸ„€

exotic chasm
exotic yarrow
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||The blue is 24/2 = 12. So the bottom leg of the left triangle is 18. Hence x=18/sqrt3 = 6sqrt3.||

slim plinth
minor heron
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oh fack i mixed up the sides i knew it was 12 but then while tryna headsolve it i mixed it up

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oops

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nvmnvm

slim plinth
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I doubt it

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It had to be a sqrt ans

minor heron
exotic chasm
minor heron
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oh the pythag triple

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i only know like 3 4 5 and that sabout it for triples who cares

slim plinth
minor heron
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never bothered learning more

exotic chasm
minor heron
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well i know 5 12 and 13 but ye

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solvable thru trig

slim plinth
minor heron
slim plinth
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That was my idea

minor heron
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uhh

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you can't figure out the angles of the other triangle

slim plinth
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10-24-26

minor heron
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dont need it

slim plinth
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After trying to use that

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X=5

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That’s not the ans choice

pale coyote
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You don't know it's a 10-24-26 triangle

slim plinth
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I do

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10-24-26 is from 5-12-13

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It’s double of its original

rustic crater
pale coyote
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It could be for example a 24-24-24√2 triangle

rustic crater
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such a shame that the other triangle isn't a right one as well

slim plinth
rustic crater
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but at least it makes it harder

rustic crater
slim plinth
pale coyote
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It can't physically be 26

slim plinth
rustic crater
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wait no

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how did you get the 10

pale coyote
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The hypotenuse of that triangle must be larger than 30

rustic crater
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i mean that side is equal to 2x via sine of 30

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but how would you be able to calculate that it's 10 with the given information

pale coyote
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It's not 10 šŸ‘€

minor heron
# slim plinth

you can't assume a pythagorean triple if thats what ur trying to do

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its not needed

pale coyote
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I think its 10√3 but that's not an option so I got no clue

slim plinth
exotic chasm
minor heron
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oh icic

somber coyoteBOT
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tsuitachi (tuitati)

pale coyote
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x=6√3

exotic chasm
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R^n moment

exotic chasm
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||-# wait pi is already in geometry||

slim plinth
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With that 2x and 24

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(2x)^2+(24)^2=y^2

rustic crater
# slim plinth

it would've made things easier if they told you that the second triangle really is right

slim plinth
rustic crater
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I think you can assume the right angle and even somewhat prove it

exotic chasm
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also btw for a 30 60 90 triangle, pythagorean triple is irrational
1:sqrt(3):2

trim stump
trim stump
slim plinth
rustic crater
slim plinth
trim stump
rustic crater
slim plinth
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I got that one 30

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Now it’s rectangle

rustic crater
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look at the angle between 2x and y

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how can it be 30 degrees

slim plinth
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Also used

rustic crater
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the angle creates between x and y cannot be a right angle as y is not parallel to 30

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which proves why that angle is not 30

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degrees

slim plinth
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This

rustic crater
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you need parallel lines

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and then you intersect them with a new segment

slim plinth
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Ohh

rustic crater
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that's when you receive the alpha angles

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the 60 degree angle up top is wrong as well, that's just assumed by you and not calculated

slim plinth
rustic crater
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anyways, there is indeed a way to prove the second triangle is a right one so

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from that point on you should be good on your own

slim plinth
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Good news is

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Proved it

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It’s another 30-60-90

trim stump
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How would u know if the right triangle is a right triangle

slim plinth
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Rt triangle has to be 90 degrees

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And sum of these has to be 180

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It is 6sqrt(3)

trim stump
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I still don't get the proof for it being 90°

slim plinth
trim stump
slim plinth
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Ok

trim stump
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Wait I'm trying to prove it

slim plinth
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Ok

rustic crater
# trim stump How would u know if the right triangle is a right triangle

because the angle formed between two triangles (where the first one is a right triangle) is a right angle, and that the longer leg of the right triangle as well as the base of the second triangle both lie on the same line, we can therefore deduce that a side of the second triangle MUST be perpendicular to the line, making it so that the angle formed between the "base" of the triangle and it's side is right. qed

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it's kind of self-explanatory I can't lie

trim stump
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Ohhh alr

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I think it's not asier to solve that nowzwait

rustic crater
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now it is way easier

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because we can use the little tool known as trigonometry for the second triangle

trim stump
torn gulch
# slim plinth

magic
||right triangle is similar to left triangle so the base opposite to 30 would be 24/2=12 30-12=18 now x:18=1:sqrt3=> x=18/sqrt3=6sqrt3=D.||

torn gulch
# slim plinth

why is this what u did dawg-OHHHHH the right triangle isn't a right triangle

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is it possible
I mean

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30 kinda indicates it is a line

slim plinth
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Is this an interesting question

exotic chasm
tiny acorn
exotic chasm
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as if the formula speaks what the shape is

tiny acorn
# exotic chasm

Is this like a square but you place 4 circles centered at the 4 vertices and subtract them from the square

exotic chasm
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and there are many curvy 4 star variations can be made with other functions, but their area formula belongs more to #calculus

slim plinth
exotic chasm
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yeah

tiny acorn
slim plinth
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Just take the quarter circle

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Merge it back in

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Then take that subtract the square

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That’s ur area of that shadow

exotic chasm
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now can we generalize for all regular polygons though

slim plinth
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So it’s A_shadow = s^2-2pir

exotic chasm
tiny acorn
exotic chasm
exotic chasm
# exotic chasm

btw its cousin, the ginkgo, is actually better\

$A=\frac 12 s^2\ P= \pi s$

somber coyoteBOT
#

tsuitachi (tuitati)

exotic chasm
tiny acorn
static lotus
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hi i am new

trail patio
exotic chasm
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should we classify pentagons like how we classify quadrilaterals?

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like by existence of right angles, same lengths, same angles... etc

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oh, also equiangular, equilateral, etc

exotic chasm
winged oyster
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people prolly wouldnt care

exotic chasm
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eh true

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it's 4 sides max that matters

shy flower
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Can anyone help me?

exotic chasm
# shy flower

should we add a "secret point" O that is the center of the circle

this.... adds nothing to actually work the solution out but now we have OBD triangle that is a right triangle

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and ODA

shy flower
grave pond
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Is there really enough information in that problem? Feels almost magical.

grave totem
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i want to complete geometory and trigno can anyone suggest me something

civic rock
# shy flower

Hint: BF is a symmedian of āˆ†DEF, so PD/PE = (FD/FE)^2. also notice āˆ†TFE ~ āˆ†TDF

tiny acorn
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<@&268886789983436800> nword

tender hull
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To know what’s the adjacent and opposite sides we take the perspective of the angle right?

tiny acorn
tender hull
tiny acorn
#

in case you dont know there are formal definitions of adjacent and opposite sides that does not require perspective

tiny acorn
tender hull
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Bet

grave pond
tender hull
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Thank you

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Could someone help me understand how we get the angles here? I feel like this is rage baiting me

slender crag
tender hull
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The other ones be crazyblobcry

slender crag
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If it was me, I would probably do them saying east as positive x axis, and during exams, if you say that east is positive x, there shouldn't be any problem

tender hull
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Thank you

slim plinth
grave pond
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Guess that the triangle is probably meant to be equilateral, and check that in that case the numbers match.

trim stump
grave pond
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Actually even without guessing that, the repeated x means it is at least isosceles, so the lower left corner must be 60°, and then the lower right one must be too.

tiny acorn
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,w 60 = log_10(x^30)

tiny acorn
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Welp solving for y should be trivial now

grave pond
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So here's a better question:

trim stump
# somber coyote

Is 60=logx³⁰ because they have the same opposite side length

trim stump
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But wouldn't that mean y=x

tiny acorn
grave pond
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Any other base would get a wrong answer, since we get x=b² and y=x because equilateral, and we need 6sqrt(y) to be 60.

trim stump
tender hull
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How do we know in general what to use? Sin cos or tan ?

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I always have issues knowing which one to use

grave pond
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When in doubt always draw a diagram.

trim stump
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Just think of soh cah toa

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And look at what's given and what they're looking for

trim stump
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So I suggest using tan

tender hull
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So when I want the opposite it’s tan

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In 20 I know I should use sin I think but idk why

grave pond
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Did you draw a diagram yet?

trim stump
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No judging ok

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Here adjacent is given

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And yours looking for the length of the tree which is the opposite

trim stump
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Look at the given length and the missing

grave pond
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I hoped I could get Kiwi to draw the diagram herself, which is more instructive.

trim stump
grave pond
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(Sorry if your diagram was not a response to my calling for it).

slender crag
tiny acorn
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We might need a !sohcahtoa at this point

oak tapir
potent hollow
exotic chasm
#

suppose lunar radius of 2 Mm, terrestrial radius 6 Mm, and center-center distance 380 Mm. how many steradian the moon covers the sky?

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would this formula work\
$\textup{coverage}=\frac{a^2+h^2}{4}$

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wait wrong formula

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but basically using spherical cap, then over 2Ļ€

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thought about this

trim stump
unkempt ember
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tan function where 5 pointed star is used as unit "circle"

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pi=10 ā˜ŗļø

slim plinth
#

Think sin/cos

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sin x: 0,1,0,-1,0
cos x: 1,0,-1,0,1

minor heron
minor heron
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alr checking rn

limber dagger
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could somebody help me with this?

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and this

tiny acorn
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Just find the surface area of all the faces and add them up

limber dagger
#

uhm

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okay

manic lynx
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What he means is: use a well-known formula about right triangles to do that

limber dagger
#

where do i even start im so confused

tiny acorn
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Nvm.

tiny acorn
#

Do you know the formula for the area of a triangle

limber dagger
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ok

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i got

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yes

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i got it right

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it says

tiny acorn
#

Says what?

limber dagger
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i did something right

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well i used

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formula sheet thing

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my teacher gave me

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idk i figured it out

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eventually.

tiny acorn
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Great. Can you solve the second one now or do you need help

limber dagger
#

let me see

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i got it

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thxs

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i just ggot it wrong the firs ttime

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idk what i did

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thanks tho

exotic chasm
#

||tadc discord server|| šŸ‘€

exotic chasm
#

thus makes it easier to calculate

exotic chasm
#

-# cos you can get height of equilateral triangle without even knowing what sin(60°) or cos(60°) is
-# and regular hexagon is 6 equilateral triangles together

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-# pentagon is kinda tricky but to get the pentagon diagonal is using similarity/congruency that later the result is has smth to do with golden ratio

old root
#

:() hi

winged oyster
#

how do i even derive the formula for area of a hexagon

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i only remembered it because i googled it so many times

tiny acorn
winged oyster
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oh yeah i forgot the hexagon is made up of triangles 😭

glass spire
#

What is the area that is in color black?

grave pond
#

By symmetry, and if we ignore the blue ostrich (?), it seems like it ought to be half the area of the circle.

wanton snow
#

i need someone to help me in geometry have an exam in a few days need a tutor to help me with my friend

exotic chasm
#

cos when one of us tutored in prism/pyramid/cylinder/cone surface area but the tested subjects are angles, similarity, and congruence, the studying becomes vain

wanton snow
#

The exam covers Modules 5 to 7 in Geometry

Angles of Triangles
Congruent Triangles
Proving Triangles Congruent (SSS, SAS, ASA, AAS)
Right Triangle Congruence
Isosceles and Equilateral Triangles
Perpendicular Bisectors
Angle Bisectors
Medians and Altitudes
Angles of Polygons
Parallelograms
Rectangles
Rhombi and Squares
Trapezoids and Kites

exotic chasm
#

....rectangles?

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isnt that just, A=ab and P=2(a+b)

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or do you have to find rectangle's diagonal or other weird stuffs like ratioes, similarity and congruence of rectangles, special ratioes like 1:sqrt(2) and 1:φ,

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also angle bisector as in, finding the special properties of triangles given a line that divides the angle by two (l=2ab/(a+b). cos(α/2))?

wanton snow
#

Yeah diagonals congruence and basic angle bisector stuff not golden ratio or those advanced formulas though

slow smelt
#

guys

slim plinth
#

So do I need two triangles

vestal basin
slim plinth
vestal basin
#

great

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wait what

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not sure if you applied pythagoras correctly...

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oh you crossed out 8^2...

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what the fuk

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ok please write every step on a separate line

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also it's 4*20 = 80

slim plinth
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And it’s (56+16sqrt(10))/108

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Then it’s A

slim plinth
marsh marlin
exotic chasm
exotic chasm
#

now let's reconstruct laws of...

  1. triangle altitude
  2. triangle median
  3. traingle angular bisector
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progress for awhile

exotic chasm
jade ether
#

is anyone actually good at geometry

raw mountain
#

Who knows

exotic chasm
small marlin
#

I'm not to sure, have you tried using a 2D truss analysis software like Ftool or SkyCiv or smth?

tiny acorn
golden island
barren shoal
#

does anyone have like trig worksheets or maybe exponentaisl šŸ’” /

jade ether
rare wave
rare wave
#

I may be able to help

rare wave
spiral lodge
#

Yeah send the question directly

jade ether
spiral lodge
#

And what about them specifically?

#

Send it, don't waste time (for us helpers and for you too)

jade ether
#

5Ɨlog (125) = 15
x

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it wouldnt copy the sub (x)

spiral lodge
#

$$5\log_x(125) = 15$$

somber coyoteBOT
#

Alberto Z.

spiral lodge
jade ether
rare wave
#

base is 5

spiral lodge
velvet pond
#

yeah

spiral lodge
#

So that we isolate the log and then maybe you'll see what to do next

jade ether
#

aigh

subtle glacier
#

Then divide all by 15 to clear all 15.

#

Which means logx(5)=1.

#

And only x can do this is that it must equal to the term inside that log.

#

But it is just the same i guess.

spiral lodge
#

Yup

rare wave
#

why is this in spanish lol

queen juniper
#

this does not belong here

civic rock
#

likely an advertisement

muted snow
muted snow
queen juniper
muted snow
queen juniper
#

wdym

rare wave
queen juniper
#

u can assign urself access to the advanced channels im pretty sure

queen juniper
muted snow
rare wave
rare wave
#

are you sure the logic is correct?

muted snow
#

yes,i sure

#

Hodge's conjecture really caught my attention and I worked on itcture

queen juniper
#

you solved hodge's conjecture?

#

i mean i've seen a lot of people here say that they've solved a millenium prize problem

muted snow
queen juniper
#

well if you actually did solve it then there's basically no chance i'll understand it

rare wave
muted snow
#

okey

rare wave
# muted snow okey

But no matter what, even if it's not justified, it's more than I can comprehend right now

muted snow
#

thanks

#

So where can I upload it?

potent hollow
#

im sorry if im mistaken but the formatting does look like chatgpt, especially the underendered latex

rare wave
muted snow
#

The layout is formatted, yes, but the ideas are mine. Every single tool, logarithm, and theorem in that text was selected by me to build the inference chain. Focus on the mathematical logic, not the template

rare wave
potent hollow
#

well congrats go claim your 1 million dollars

rare wave
tiny acorn
#

Prove it to the mathematical journal

potent hollow
#

i wonder how much sarcasm were allowed

tiny acorn
#

Oh wait they got muted cuz they spammed the paper and i reported them

queen juniper
#

yeah there have been multiple ai "proofs" sent in these channels

tiny acorn
potent hollow
#

surely one will actually prove it eventually

tiny acorn
exotic chasm
#

wait, dilation can just scale in 1 axis only?

tiny acorn
#

If you dilate along x axis and y axis by different amounts it wouldnt be similar

tiny acorn
#

Like dilation is synonymous with scaling i think

exotic chasm
#

cos iirc dilation, at least with matrix, it's
k 0
0 k

tiny acorn
#

Im just like

#

You can scale shit unevenly

exotic chasm
#

a 0
0 b
matrix for starter

tiny acorn
#

For me its just multipling the x and y coords with a scale factor k

#

So (x;y) -> (kx;ky)

exotic chasm
#

eh it does the same

tiny acorn
#

(I assume the matrix does the same thing)

#

(In fact i think it does)

#

Uneven scaling has like numerous applications tho

#

When you select shit and scale it unevenly in cad, paint n stuff

slim plinth
#

I wonder if we can use A=1/2 bh to proof a polygons

#

With A=1/2 a P

tiny acorn
rare wave
slim plinth
tiny acorn
slim plinth
tiny acorn
#

Err im not getting what your saying

slim plinth
#

With is 1/2 a P

tiny acorn
slim plinth
#

a is the apothem and P is the perimeter

tiny acorn
#

But ye

slim plinth
#

Then replace them to get
A=1/2 a P

#

If I set them equal

#

Then it’s bh=aP

rare wave
slim plinth
#

This kind

rare wave
#

then pa/2

#

[ sigma x_i y_{i+1} - sigma x_{i+1} y_i]/2

#

this can be used for all polygons

muted snow
# rare wave could you like produce a logical, formal maths style proof?

Hey Cealum, thanks for asking and for your respectful attitude earlier. To answer your question: yes, I can provide a formal proof. The ideas and the logic are 100% mine, developed by hand. I only used formatting tools to write down the LaTeX formulas neatly, which unfortunately made some people here paranoid about AI. If you ask any AI to solve Hodge, it will fail because they can't create new logic. I’m leaving this server now because the community rules aren't being respected and I'm not interested in a place where people rely on memes and insults instead of actual math. Wish you the best in your studies

tiny acorn
#

Like

#

If you seriously wanted ppl to read it

muted snow
tiny acorn
#

Have it in english

tiny acorn
#

In english

#

You paper isnt in english

muted snow
tiny acorn
#

Most people can not review it

tiny acorn
#

So its best if you provide your own translation

muted snow
#

That's what translators are for

#

Are you hurt or what?

tiny acorn
muted snow
#

It hurts your pride

tiny acorn
#

As an author you should strive to make it accessible for everyone if you want ppl to read it

muted snow
#

It hurts your pride

#

Are you hurt or what?

#

Did you actually analyze the logic or do you only come here to post memes because reading actual math gives you a headache? Tell me exactly which step of the inference fails or just stay quiet

#

use the translator

tiny acorn
#

Rule 1

#

No fallacies

muted snow
#

nope

#

You don't even respect your own rules and you come here to teach me about them.

tiny acorn
#

Wow it hurts my pride that i can not understand Portuguese or whatever that was written in

muted snow
tiny acorn
#

So i wouldnt use it

#

Also you cant pull any other argument besides "it hurts your pride"

muted snow
#

You made fun of me when I tried to send something serious that you didn't even bother to look at, so don't talk to me like a professional.

tiny acorn
muted snow
#

And if it's supposed to be AI according to you, you can use it to understand what I wrote, or if you want I can explain it to you here

muted snow
#

Here is the core logic:
​Green's Current & Residues: I define a Green's current G for the cycle Z. Applying Stokes' Theorem on the singularity log |s|^2 forces the Hodge class coefficients to be strictly rational (\mathbb{Q}) via logarithmic residues.
​Siu's Theorem: The Lelong number (local density) of this closed positive current is strictly positive, which mathematically guarantees that the support Z forms a complex analytic subvariety.
​Chow's Theorem: Since X is a smooth complex projective variety, Chow’s theorem ensures that this analytic subvariety is necessarily algebraic (defined by polynomials).
​The bridge from Analysis to Algebra is closed. If you have an actual mathematical counterargument to any of these three steps, I'm listening

raw mountain
#

Where is the question I need to disprove

tiny acorn
#

Or integrals

#

Or whatever

muted snow
#

Do you understand it or not?

exotic chasm
raw mountain
#

You assumed the missing step?

muted snow
# raw mountain Siu's theorem only makes positive-Lelong level sets analytic, it doesn't produce...

That’s exactly where the Green's current construction and regularized analysis come into play. We aren't starting from an arbitrary non-positive class; a Hodge class \omega of type (p,p) on a projective manifold allows the construction of a log potentials singularity system.
​By using the dd^c-lemma and the global green's function G = \log|s|^2, the singularity structure precisely mirrors the topological data of the class. The Lelong number \nu(T, x) isn't just 'positive' by chance; its values are strictly locked to the discrete residue multiplicities forced by Stokes' theorem on the logarithmic singularity. That guarantees the existence and integrality of the dense support, which Siu bridges to analyticity and Chow to algebraicity. The representation isn't arbitrary; it's structurally forced by the dd^c equation.

raw mountain
#

Yeah you can't type this fast

tiny acorn
raw mountain
#

That was copy pasted

#

I can tell lmao

tiny acorn
raw mountain
#

Straight from AI

raw mountain
#

Tell that to your AI

muted snow
# raw mountain You assumed the missing step?

I didn't assume it, it's structurally forced by the geometry of smooth complex projective varieties. A Hodge class is not just any random topological class; by Hodge theory, it contains a unique harmonic (p,p)-form.
​Because X is projective, we can use the dd^c-lemma globally. The Green's current G is constructed precisely as the solution to the equation dd^c [G] = \Delta(Z) - \Omega, where the singularity behavior is strictly controlled by the local log potentials. The positivity of the current and the integrality of the Lelong numbers aren't arbitrary assumptions; they are the direct topological consequence of applying Stokes' theorem to the logarithmic residues of that global green function. Every step of the inference is locked by the differential architecture of the variety

raw mountain
#

Alright you guys have seen that right

raw mountain
#

!noai

lime crownBOT
#

Please do not trust ChatGPT or similar AI tools for mathematical tasks, as they often generate output which "sounds correct" but has numerous factual or logical errors. Use of these AI tools to answer other people's help questions is strictly against server rules (see #rules).

lime crownBOT
tiny acorn
tiny acorn
raw mountain
#

AI Slop

#

A bad one

tiny acorn
#

At least it isnt collatz

raw mountain
#

Probably using Chatgpt Free Tier

tiny acorn
#

Or rh

tiny acorn
raw mountain
#

Instant mode šŸ’€

#

That's why it was so fast

tiny acorn
#

Hmmm math slop

#

Pretty sure finding y is trivial

#

,calc (180-48)/2
180-68

somber coyoteBOT
#

Results:

66
112
tiny acorn
#

,calc 180-(360-243-66)-112

somber coyoteBOT
#

Result:

17
tiny acorn
#

y=17°

slim plinth
#

I got y=20 degree

exotic yarrow
exotic yarrow
slim plinth
#

Two sides are same then two angles are the same

nocturne breach
# slim plinth

In isosceles ABD the angles must add to 180, so 2ADB+48=180, ADB = 66, and the interior ADC should be 360-243=117, and DCB supplementary to BCE so BCD is 112, in the end u get y = 17

nocturne breach
slim plinth
#

Okay

nocturne breach
nocturne breach
slim plinth
#

Okay

#

I wonder what would the tick mark looks like if there parallel

#

Is it two arrows

nocturne breach
#

It would be like an arrow going through it

#

Yes I believe so

#

The tick marks mark they are the same, so the base angles in the isosceles triangle are the same

slim plinth
silent plank
#

Wdym half of angle D

slim plinth
#

So it’s

silent plank
#

if it's not exactly half, don't say half

slim plinth
#

66+117+112+48+y=360

#

Is that right

silent plank
#

use three points to describe your angle

slim plinth
#

So it’s

#

Angle ADB and Angle DAB = 66 degrees then it’s Angle ADB=Angle DAB

slim plinth
silent plank
#

Yes

slim plinth
#

How would u solve this

nocturne breach
slim plinth
#

When I see this I almost used pythagorean theorem, but then I thought there is a rt angle

#

So I can’t use it

silent plank
#

there are trig rules for non-right triangle

slim plinth
#

Can we use trig

nocturne breach
#

Dyk law of cosines?

slim plinth
#

Now that’s what it looks like

nocturne breach
slim plinth
#

30-60-90

nocturne breach
#

Yes

slim plinth
#

90 is 2x=3

#

x=3/2

nocturne breach
#

Whoa where

#

First try to find the height of the altitude from the small 30-60-90, and then use pythag

slim plinth
nocturne breach
#

Yea that’s right

slim plinth
#

Yay, Pythagorean theorem time

#

After that I got x=sqrt(283)/2

#

Can I simplify sqrt(283)

silent plank
#

how'd you get that?

slim plinth
nocturne breach
# slim plinth

It’s not 8^2, it’s (8-3/2)^2 cuz ur taking the leg of the right triangle not the big triangle

slim plinth
#

Ohhh

nocturne breach
slim plinth
#

49

nocturne breach
#

Sqrt that and you’d get 14/2=7

slim plinth
#

Yes it’s 7

slim plinth
#

Then x=y

exotic yarrow
#

don't love that but it is what it is

slim plinth
#

That’s what I got

exotic yarrow
slim plinth
#

yay

#

x=y

snow isle
#

Props to you

slim plinth
#

Thanks

plucky crag
# slim plinth Yes it’s 7

unsure if this is in your course, but a nifty trick anyway is to just use cosine law x^2 = a^+b^2 -2abcos(c) (in this case a= 3, b=8, and C=60 degrees)

#

it works on any triangle if you have two sides and the included angle, you can find the last side. pretty neat

#

if its not in your course i recommend learning it and using it to check your answers

#

just takes less working out from your way

plucky crag
slim plinth
#

Ohh

#

So it’s 3^2 + 8^2 -2(1/2)

#

9+64-2=71

plucky crag
#

sqrt 49 = 9

#

so a^2 +b^2 -2 x ab x cos (C) dont forget the 2x ab part

slim plinth
#

You mean 7?

plucky crag
#

:/.

plucky crag
#

i swear im good at maths 😭

#

but you see how it works now?

minor heron
plucky crag
plucky crag
#

the duality of a math student

minor heron
vocal sentinel
#

AP?

exotic yarrow
minor heron
# vocal sentinel AP?

Ap is a American education system thing. ā€œCollege levelā€ stuff with exams in may that give u college credit if u pass and a gpa boost

marsh marlin
slim plinth
minor heron
#

Why sleep when you can math KEK

marsh marlin
marsh marlin
minor heron
#

Yes I can watch me

#

(Dreams about solving a frq)

marsh marlin
#

but you can sleep without math

marsh marlin
minor heron
#

/jk

winged oyster
winged oyster
#

advanced placement sleep is the pro strat

vocal sentinel
#

Antagonising People.

somber coyoteBOT
#

tsuitachi (tuitati)

vocal sentinel
#

Try draw it out

exotic chasm
#

the proof that i can make actually uses the fact that d2=sqrt(h^2+b^2), d1=sqrt(h^2+a^2)

#

thus applying A=(1/2)h(a+b)

#

while getting h=(b-a)

#

but this requires the parallel lines' length

exotic chasm
#

just realized šŸ¤¦ā€ā™‚ļø

plucky crag
#

also if you go sqrt(49) and just like get rid of the sqrt and 4 then 9=9

#

sooooo

sly jackal
#

Yoo guys I am having some problems regarding trigonometry

#

I can't even learn the formulas I am doomed catcros

#

@somber coyote

lime crownBOT
#

Asking the actual question right away is more likely to get responses.

Asking "Can I ask...?" or "Does anyone know about...?" doesn't give people enough information to decide whether they can help, and answering can feel like a promise to help with the actual question, which they might find themselves unable to.

exotic yarrow
#

(also texit is a bot)

exotic chasm
tiny acorn
sly jackal
exotic chasm
exotic chasm
#

oh, you habe difficulty in remembering the formula?

sly jackal
#

@exotic chasm

exotic chasm
#

tbf there's no mnemonics on how trigs work so šŸ¤·ā€ā™‚ļø

#

yeah i guess one can only go the hard way, by actually using the hard trig concepts irl

exotic chasm
#

oh, there's actually a """""clutch""""" that makes trigonometric additions """""easier""""". namely, complex numbers

plucky crag
# sly jackal Yess dude I can't remember it

literally just spam revision questions, and when writing questions do full exam style working outs, so write out the formulae you use, then sub in values and then solve. doing this will increase your familiarity with the forumulae

sly jackal
exotic chasm
#

which, is entirely different demon, but once you know the oiler formula

e^(zi) = cos(z) + sin(z) i

trigonometry stops being tricky

#

because while sin cos tan disallows you to do easy calculations once you insert a+b or smth, exponents, in other hand, allows

plucky crag
exotic chasm
#

$\sin(a+b) =\frac{e^ae^b-e^ae^{-b}}{2i}$

somber coyoteBOT
#

tsuitachi (tuitati)

exotic chasm
#

oh wait

exotic chasm
#

cos i oftenly told that way 😭

#

like, i genuinely thought that all memorization can be skipped by just counting them in the terms of complex form

exotic chasm
plucky crag
#

so is there like euler form formulas for most trig identities like sin (a+b) or is this like a specific one

exotic chasm
#

can be made

exotic chasm
exotic chasm
somber coyoteBOT
#

tsuitachi (tuitati)

exotic chasm
#

oh then when sin(a)sin(b)sin(c) or other weird forms can use complex form

plucky crag
#

how can sin (a+b) (assuming a+b are real numbers) = a complex number but if you use the normal formula it equals a real number (sin(a+b)= sina cos b +sin b cos a )

plucky crag
#

oh wait sorry i didnt see the 'i' in the exponents do they cancel out

#

oh yeah

#

whoops

tiny acorn
exotic chasm
#

now i just remembered, that cos(2Ļ€/7) even involve the imaginary unit, YET, a real number

tiny acorn
#

But

#

How

#

Do you cancel it

exotic chasm
tiny acorn
exotic chasm
#

wait, this stops being trigonometry and starts being complex numbers

tiny acorn
plucky crag
#

its the same as trig tho so its fien

plucky crag
dense fossil
#

It starts from the e^x infinite series which is sum n=0 to infinite of (x^n)/n!

When you plug in ix (meaning e^(ix))

You get 1+ix-x^2/2!-ix^3/3!+x^4/4!..... which when we group the real and the complex we get one part being 1-x^2/2!+x^4/4!..... and the other being ix-ix^3/3!+ix^5/5!..... which is same as i(x-x^3/3!+x^5/5!....)

The first part which is the real gives cos(x) because thats the infinite series for cos(x) while the imaginary part it gives you i*(infinite series for sin(x)) which is isin(x) .

The e^(-ix) its the same idea, but this when grouped gives cos(x)-isin(x).

So by doing e^ix -e^(-ix) gives cos(x)+isin(x)-(cos(x)-isin(x)) whcih is 2isin(x) then to get sin(x) we divide by 2i.

exotic chasm
#

also should we normalize short trig notations in sake of proving trig idents

#

$\sin(a)=S_a$

somber coyoteBOT
#

tsuitachi (tuitati)

exotic chasm
#

like that

tiny acorn
exotic chasm
#

😧

exotic chasm
dense fossil
#

It could potentially get into other function territories such as would sec(a) also be $\sec(a)=S_a$

somber coyoteBOT
#

ćƒ­ćƒŖćƒŖćƒ“ć‚µ

exotic chasm
exotic chasm
tiny acorn
exotic chasm
#

for sec csc cot
$C_a^{-1},S_a^{-1},T_a^{-1}$

somber coyoteBOT
#

tsuitachi (tuitati)

dense fossil
#

but that would look too much like inverse functions

exotic chasm
#

oh also we can reduce the character count again by defining m=-1

tiny acorn
exotic chasm
#

that said this is the exact reason i actually like using arcsin instead of sin^-1

#

and when i want to use 1/sin, i write
(sin(x))^-1

dense fossil
exotic chasm
#

or just straight up csc

tiny acorn
exotic chasm
tiny acorn
#

Standarđize the sin notation, sin(x)....n times .... sin(x) = sin(x)^n
arcsin(x) = sin^-1(x)

#

It kinda isnt that hard

#

Why do we keep having to use sin^n(x) for (sin(x))^n

#

?????

exotic chasm
#

tbf arcsin vs sin^-1 thing reminds me of the
f^-1 being inverse of f instead of 1/f

exotic chasm
#

but f^2 (x) means (f(x))^2 somehow

#

🤣

tiny acorn
#

Why are trig functions so special

#

Just like

#

Be every other function

exotic chasm
#

for inverse of f

tiny acorn
#

And follow f^n(x) = f(f.n times.f(x).)

tiny acorn
#

This like opencry worthy

slim plinth
#

What about f^-1(x) = 1/f(x)

tiny acorn
slim plinth
#

What about
P^-1(larp) = 1/P(larp)

tiny acorn
exotic chasm
#

yeah enough of talking abt this
now return to calculating area of a kite

slim plinth
#

I love that

slim plinth
#

It’s the product of two diagonals divide by two

tiny acorn
#

Just sum the halves up

tiny acorn
slim plinth
#

Guess the formula
A=((d1+d2)(h))/2

tiny acorn
tiny acorn
slim plinth
#

Or h^2

tiny acorn
slim plinth
#

The rectangle in red

#

Is bh

#

Square in blue is a square

tiny acorn
slim plinth
#

Or b^2

tiny acorn
#

It just so happens to look similar to a square in this case

slim plinth
#

So it’s bh

#

But it’s b2*h2

tiny acorn
slim plinth
slim plinth
#

Or length*width

tiny acorn
#

@slim plinth i was thinking this

#

It was supposed to be 1/2*d_1 there not 1/(2d_1)

slim plinth
#

Then u use 1/2 bh

tiny acorn
#

Can you draw a diagram

exotic chasm
tiny acorn
exotic chasm
#

yeah my back

it's kinda itchy

tiny acorn
crimson glade
exotic chasm
#

wait, would line marked with s and t be perpendicular to each other

exotic chasm
# crimson glade

btw can i give more point marks for this img so we can say which is which

#

like this

exotic chasm
#

because if it is, then s and t should be the same, and not different

crimson glade
exotic chasm
#

hmm

vocal sentinel
#

Two triangles

exotic chasm
vocal sentinel
#

If can't, try to show triangle AED similar to triangle AFD

exotic chasm
exotic chasm
vocal sentinel
#

You want to find angle DAB

exotic chasm
#

well, for any quadrilateral, since the inner angle sum is 360°, when angle AEF AFD AED are 90°, EDF must be 90° too

#

oh wait

vocal sentinel
#

So can you show those 2 triangles similar?

#

Using Angle - Angle

exotic chasm
#

via AAA

#

as in angle angle angle

vocal sentinel
#

Yes, how?