#geometry-and-trigonometry

1 messages · Page 298 of 1

upper karma
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no it's not

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...

dark sparrow
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can i see the problem again

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i have a feeling there isn't enough data

little osprey
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Ann

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polynomial

upper karma
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there isn't

little osprey
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will get angry

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if you interfere

upper karma
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but you pretty much have to assume

azure reef
upper karma
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@dark sparrow here was the problem

silent plank
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the only answer that would make sense here would be the arc measure

upper karma
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i know

little osprey
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Which I already mentioned

dark sparrow
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we don't know how long the hour hand is

upper karma
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so my answer should be right

dark sparrow
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there is no right answer to this

upper karma
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ann yes

little osprey
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Bruh your answer?

dark sparrow
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there is no right answer

little osprey
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You told him to ignore me

silent plank
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which will be independent on the diameter and radius

dark sparrow
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simple as that, there is no right answer

upper karma
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20.9375

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was my answer

azure reef
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the only answer that would make sense here would be the arc measure
why cannot we express hour hand as some function of diameter tho

arctic vortex
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20.9375
@upper karma that wasnt right unless i had to round to whole numbers

dark sparrow
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we don't know how long the hour hand is!!!

upper karma
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What if they want radians

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An angle

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@arctic vortex how am i supposed to know what you're supposed to do

little osprey
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Yes we have established that

arctic vortex
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we don't know how long the hour hand is!!!
@dark sparrow 12 to 6 is 180 degrees

silent plank
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because we have nfi how long the hour hand is relative to everything else

dark sparrow
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who's to say whether the hour hand is 5 inches long or 4 inches long or 3 inches long?

arctic vortex
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180/6

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is 30 degrees

dark sparrow
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do you even read what i'm saying

arctic vortex
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yes

dark sparrow
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WE DON'T KNOW THE LENGTH OF THE HOUR HAND

arctic vortex
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wait

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but

dark sparrow
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WE DON'T KNOW THE LENGTH OF THE HOUR HAND

azure reef
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because we have nfi how long the hour hand is relative to everything else
well yes, but i mean general form
it will involve arbitrary constant

dark sparrow
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we don't know how big it is

little osprey
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lmfao

upper karma
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...

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there is no way it will involve a constant lol

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my answer should be right

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the question is if they want to round it to 21

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@arctic vortex try 21?

dark sparrow
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aight yall clowns wont listen to me i get it

upper karma
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ANN

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they clearly want a real number

dark sparrow
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look

upper karma
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there's no entry box to write "impossible to solve"

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I AGREE

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WITH

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YOU

dark sparrow
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for all i know, the hour hand could be any length between 0 and 8 inches

upper karma
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YES BUT THERE'S NOWHERE TO WRITE THAT FACT

dark sparrow
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it's pointless to try to guess

little osprey
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aight yall clowns wont listen to me i get it
@dark sparrow Read the chat history.

dark sparrow
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spiral should email their teacher

little osprey
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Agree

dark sparrow
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and be done with this problem

upper karma
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i guess

little osprey
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@arctic vortex try 21?
@upper karma Did you keep units

azure reef
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this problem certainly does not deserve such hot discussion

upper karma
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@little osprey not sure what you mean by units

little osprey
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inches

arctic vortex
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no its wrong

little osprey
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Yeah

upper karma
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well no idea then

little osprey
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Email your teacher

upper karma
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send an email

arctic vortex
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ok but

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how do i solve this

upper karma
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LMAO

dark sparrow
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wow

upper karma
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you know that dj khaled song

dark sparrow
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smoothest segue in the west

upper karma
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another one

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im crying

arctic vortex
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i dont know how to find the tangent

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why are u crying

little osprey
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Suffering from success

arctic vortex
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what happened

upper karma
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spiral

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does it show you the answer to the previous problem

arctic vortex
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no

upper karma
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yeah, i want an update when you email your teacher

arctic vortex
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ok

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i think the hour hand is 30 degrees

little osprey
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Actually, same

arctic vortex
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though

little osprey
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time doesnt go backwards

upper karma
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For this one, recall a circle theorem

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wait

arctic vortex
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no becasuse 12 and 6 are equal right

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like they are opposite

upper karma
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do they want degrees?

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but why would they mention the diameter then?

arctic vortex
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meaning that 12 and 6 are semi circles

upper karma
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doesn't make any sense

little osprey
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huh

arctic vortex
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and since there are 6 hours in 180 degrees

little osprey
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d x pi = circumference

arctic vortex
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180 / 6

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so its 30 degrees

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each hour hand

upper karma
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yes

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that's correct

little osprey
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doesn't make any sense
@upper karma What are you on

arctic vortex
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yeah

little osprey
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I mean

arctic vortex
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and you guys ssaid that it was wrong :(((

little osprey
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like what are you talking about

upper karma
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denton

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it could be the case that they just want an answer of 150 degrees

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but that doesn't make sense, since they mention the diameter

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to summarize

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it's one of the worst questions i've seen in a while

arctic vortex
upper karma
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What do you think?

arctic vortex
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i dont know

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the difference

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ohh

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if it says area its sector

arctic vortex
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my geometry finals are coming up and i think i will fail any tips for me

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to pass

upper karma
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Bruh

arctic vortex
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or anything i should study more

upper karma
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yes get questions that make sense

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that's step 1

arctic vortex
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..

upper karma
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You posted 2 problems and literally skipped them?

arctic vortex
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yeah this one

upper karma
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For this one, recall a circle theorem

arctic vortex
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whats the circle theorem

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If inscribed angles of a circle intercept the same arc then they are congruent. This follows from the Inscribed Angle Theorem. 7. If two chords intersect within a circle, the product of the measures of the segments of one will be equal to the product of the measures of the segments of the other.

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this one

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no wait this is tangent

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wait

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help

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nvm

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i think i got it

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how do i do this

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nvm i got that

upper karma
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lol

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something tells me you're not even trying the questions before asking

arctic vortex
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i am

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but i dont know the formula to solve it

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for the rachel one i just solved the area and divided by 6

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and did 12pi = 18.85

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and 6pi

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3pi

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pi

royal edge
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I think my notes are wrong. It says z-scores are the standardized scores for x values. Is that wrong or correct

small perch
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I don't understand what it wants me to do.
I converted 325 degrees to 5.672320069 radians. However, I'm not sure what it wants me to do next.
Do I divide by pi? - (Express in terms of pi)
Do I insert 5.67 into the s, and 12ft into r, for O=S/R?
Any help would be appreciated.

silent plank
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don't round until the end, until then keep your values in terms of pi. (just use the expression that you entered in your calc before pressing =)

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s is what you're trying to find

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the central angle will be theta

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and s = r * theta

dusk stratus
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could someone please explain how they got arctan(1/-1) to be 3pi/4? the answer i got was -pi/4, and it seems like they got the supplementary angle as an answer of the angle that i got?

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and the range of arctan lies in the first and fourth quadrant, so that also confuses me

silent plank
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they're using improper notation / function

azure reef
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they take main interval as (0, pi)

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which is bad since tan is undef on pi/2

silent plank
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they should be using the atan2 function

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theta = atan2(1,-1) = arctan(-1) + pi

dusk stratus
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but why do they use the atan2 function here? is it because im dealing with complex numbers?

silent plank
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the arc functions have limited range

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it apples to the terminal positions of real points too

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you need something to account for things that are in quadrants 2 and 3

dusk stratus
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oh! so Q2, i add pi, and Q3, i subtract pi

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am i right?

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or

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the complex number im dealing with is -1+i, which would lie in Q2

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so it would make sense to add pi?

silent plank
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yes

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technically you don't need to know about the existence of the actual atan2 function.
just know about properties of the arctan function, quadrants and how to perform the appropriate shifts

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(so there's no need to memorise it verbatim)

dusk stratus
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yeah, i havent used the atan2 function for anything in a long time

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but i get how it works :) tyy

small perch
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Sorry, I didn't respond sooner. I am also working and we have been really busy today.

So, i take 5.672320069*12=68.06784083

How would I write this in terms of pi? Do I divide by pi?

silent plank
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(just use the expression that you entered in your calc before pressing =)

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i.e. to convert 325° to radians I'm assuming you did:

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$325 \times \frac{\pi}{180}$

somber coyoteBOT
small perch
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I'm not sure what you are referring to sorry.
5.672320069 is 325 degrees converted to radians. then I multiplied by 12 (ft) to get 68.06784083.
I'm just not sure where I'm going wrong.

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No my calculator did the conversion for me

silent plank
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and that although unsimplified will be the exact value of your angle in radians

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oh...

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in that case learn the conversion that pi = 180°

small perch
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How do I simplify 68.06784083 more than it already is? Well I supposed it can be rounded. So 68.07.

silent plank
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the instructions are confusing as fk

small perch
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Yes, they are lol

silent plank
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i mean you did round correctly to 2dp

small perch
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I might need to get my teacher to clarify what it actually wants.

silent plank
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so i'm assuming they actually want you to keep stuff exact

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so try not to rely on the calculator for certain calculations

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keep everything exact

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specifically the angle would be what I wrote above

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and multiply that by 12 (ft) for arc length

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$s = \frac{325 \times 12 }{180} \times \pi \text{(feet)}$

somber coyoteBOT
small perch
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oh okay. I'll try that thank you so much

silent plank
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and use appropriate tools to simplify that fraction

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(express it as an improper fraction because mixed numbers are crap)

small perch
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great that worked thank you

dark shuttle
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I really need help

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with finding the "domain of validity" of an expression

cosmic pebbleBOT
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Rule 1

The help channels are solely for help with math, so feel free to post your question. Asking whether you can ask a question or if anyone knows about some specific topic is unnecessary, so please try to avoid questions of that nature.

idle bobcat
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Hello quick question: When people calculate area, they say their final answer is in units squared. But isn't the squared portion of the unit not relevant once you reach a final answer? Like say you have a 5x5 square, why does it make sense to say the final answer is 25cm^2?

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I would understand if they said it the area was 5 squared, but I feel like I'm missing something

upper karma
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???

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but isn't the square portion of the unit not relevant once you reach a final answer
??

idle bobcat
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?

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Like you wouldn't say the answer is 25^2

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you would just say 25

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But apparently you DO say 25^2 is the final answer

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and thats why I'm confused

upper karma
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Uhh? For a 5cm side length square area, A=l² so A=5*5=5²=25 cm²

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Its not the same 25² than 25cm² which is the correct form

idle bobcat
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why is the unit of measurement squared?

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is it because 5cm*5cm = 25cm^2

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i guess that makes sense

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but using units in a formula is new to me so doesn't feel intuitive i guess

upper karma
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Yeah fair

pure pivot
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Can anyone help me out with this graph

pure pivot
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Anyone

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<@&286206848099549185>

idle bloom
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Everything is right except the vertical shift

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Remember the vertical shift is halfway between the maximum and minimum

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Oh wait

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Amplitude also needs fixing

pure pivot
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What’s wrong with the amplitude

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4-1=3

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Ohh

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Can you help with me with the vertical shift

idle bloom
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4-1=3
@pure pivot
how did you get 1

pure pivot
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4-2/2= 1

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D=1

idle bloom
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yea

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you added the max and min

pure pivot
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4-1=3

idle bloom
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and divided by 2

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and got 1

pure pivot
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Yes

idle bloom
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that's your vertical shift

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+1

pure pivot
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For this graph isn’t there a phase shift

idle bloom
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it's not a phase shift

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it's a vertical shift

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so instead of +2

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you should have +1

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you said D = 1

pure pivot
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Ok I got that

idle bloom
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D is the variable commonly used for vertical shift

pure pivot
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Yes

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But does this graph have a phase shift?

idle bloom
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if you write it as a -cosine

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it doesn't have a phase shift

pure pivot
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Cause rn I’m 3cos(pi/4x)+1

idle bloom
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-3

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not 3

pure pivot
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Why is it -3

idle bloom
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or if you want to use 3

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then there's a phase shift if you want to use 3

pure pivot
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Ohh nvm

idle bloom
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you get why it's -3?

pure pivot
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The graph goes up and it’s cod

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Cos*

idle bloom
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cause we start at the minimum, reach the midline, then the max, then the midline, then back down to the minimum

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that's the pattern for -cosine

pure pivot
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I got it

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Thank you

idle bloom
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👍

sinful anvil
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Lol

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I’m supposed to find a sine and cosine function for the graph. Sorry that it’s sideways lol

upper karma
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,rotate

somber coyoteBOT
upper karma
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anyway the sine and cos are going to be the same, just slightly different argument, since one will be a pi/2 - x shift of the other one up to other shifts and transformations

sinful anvil
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It’s in degrees lol

upper karma
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ok

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note that

sinful anvil
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I didn’t even start the 11th grade lol

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I’ll take note

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For the sine function

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I had f(x)= 4 sin(x - 270*) - 3

upper karma
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,w sin(x + pi/2) = cos(x)

somber coyoteBOT
upper karma
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not sure why

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but anyway

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pi/2 = 90 degrees

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same thing, just wolframalpha doesn't like it for some reason in here

crystal quiver
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hello

sinful anvil
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Lol

crystal quiver
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@upper karma

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can u help me

upper karma
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why would you immediately tag me

crystal quiver
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to get ur attention

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sorry

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can u help me pls

upper karma
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idk

sinful anvil
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Is f(x) = 4 sin(x - 270) - 3 right?

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For the sine function

azure reef
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wdym

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here?

sinful anvil
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👍

azure reef
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but why you even need shift of sine here

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it is pure sine

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graph depicts literally 4sin(x)-3

sinful anvil
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Oh, I’m dumb af

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I didn’t realize that lol

azure reef
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well, if you want shift you can shift by 2pi and get the same

sinful anvil
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So I now have the sine function

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Now for the cosine function lol

azure reef
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you want to find f(x)=some function of cosine

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with the graph above?

sinful anvil
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Yeah

azure reef
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well, you can use that sine is cosine shifted

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for example, cos(x)=sin(x+pi/2)

sinful anvil
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The question was « Determine 2 equations using the parent functions sinx and cosx »

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I had an equation for cosine as well

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But I think I’m being retarded again

azure reef
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question is badly worded ig

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what does mean determine two equations

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"equation" imply that they should be equal to something

sinful anvil
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For the curve, it wants me to find a sine equation and a cosine equation

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Using parent functions

azure reef
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well for cosine one

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parent function is cosine

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is it obvious that it is also 4cos-3?

sinful anvil
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To me it wasn’t obvious. It was my 1st time working with Trig functions

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I only guessed the equations based on the amplitude and the horizontal shift

azure reef
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wtf was that

sinful anvil
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Idk

azure reef
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wel for trig remeber

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that sine-cosine have amplitude 2

sinful anvil
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Can you not @pallid sierra

azure reef
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that sine-cosine have amplitude 2
since they both lie in [-1, 1]

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so that's why you need multiply by 4

sinful anvil
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Oh

azure reef
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and -3 you need since sine is 0 at 0

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but graph shown -3

sinful anvil
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👍

forest niche
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Does anyone know how to graph this

upper karma
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yes

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watch this insane shit

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,w graph -3csc(2x + pi/4)

somber coyoteBOT
upper karma
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insane right

forest niche
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Lol I have to find the points

upper karma
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well then

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have fun plugging in marginally smaller and bigger values

forest niche
azure reef
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@forest niche wdym graph

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i mean which precision of graph you want

forest niche
azure reef
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ok so

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csc = 1/sin(x)

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where do u think there will be asymptotes

forest niche
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Every pi/3

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Pi/b

azure reef
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what

forest niche
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Isn’t that the formula to find the asymptote

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;-; I’m sorry I’m lost

upper karma
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Use common sense, if csc(x)=1/sin(x) we'll look at when the denominator equals 0

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@forest niche

forest niche
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Wdym I’m sorry my trig is horrible

upper karma
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That was not trig really

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Uh

forest niche
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Idk I’m stupid I guess ;-;

upper karma
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$\csc(t)=\frac{1}{\sin(t)}$ and we want to see where the denominator equals 0, which will give us the vertical asymptotes

somber coyoteBOT
upper karma
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Or better lets just find the domain

forest niche
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Isn’t the domain all real numbers

upper karma
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well....

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the domain is approximately...

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i better not say it, i will anger the ann

dark sparrow
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too late lmao

forest niche
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It’s ok I’ll figure it out

upper karma
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the domain is $\mathbb{R} \setminus {0}$

somber coyoteBOT
upper karma
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Oh f i closed the app and the text i was writing got deleted

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Ill write it again ig

forest niche
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It’s whatever I’m gonna watch some more YouTube videos it’s not a big deal

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Thanks for trying to help

upper karma
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...

somber coyoteBOT
azure reef
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lmao

upper karma
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yes

azure reef
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,w csc(588727723pi)

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really?

upper karma
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see, it's equal to the conjugate of infinity

azure reef
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but it is complex infinity

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and infinity itself is NaN

silent plank
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@upper karma with no respect at all if you're gonna deliberately spout misinformation please fuk off

upper karma
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😦

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tbh i just forgot what function we were talking about lol

azure reef
#

If you do not know what we are talking about, do not interfere

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@forest niche

somber coyoteBOT
silent plank
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variable fk up

forest niche
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Wait what I didn’t even say anything

azure reef
#

so as it was said it wail to exist when sine is zero

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variable fk up
@silent plank it is plan!

somber coyoteBOT
azure reef
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so look

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it fails to exists and results in asymptote when sin is 0

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because limit of 1/x as x -> 0 is inf

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that means that for asymptotes you need sin(t)=0

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when sine is zero

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do you know it?

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@forest niche

forest niche
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I’m genuinely lost rn

azure reef
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well what do you know about sine?

forest niche
#

Idk sine=O/H? 😂

weary drift
#

i expected at least 10 copswings on poly's last latex

azure reef
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well 4

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Idk sine=O/H? 😂
what

weary drift
#

that's better but not enough

forest niche
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Yea idk what you wanted

azure reef
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what is O/H

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do you know anything about sine?

forest niche
#

Opposite/Hypotenuse

azure reef
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oh yes

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nice

forest niche
#

Idk what else are you looking for

azure reef
#

well

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,w unit circle

forest niche
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Oh

upper karma
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good one vimes

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,w define unit circle

somber coyoteBOT
forest niche
#

Sin = y cos= x?

next jackal
#

Somebody said that trigonometry is more about circles than triangles

upper karma
#

pretty shit illustration ngl

azure reef
#

Sin = y cos= x?
@forest niche yes

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shitty drawing

somber coyoteBOT
azure reef
#

is angle

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@forest niche is this drawing undertandable for u

forest niche
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Yea

azure reef
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so look, when sine will be zero then

forest niche
#

It touches the x axis

azure reef
#

or what is the value of angle?

forest niche
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Idk angerysad

azure reef
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just look at drawing

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what angle makes radius with x-axis when y-coordinate is zero

forest niche
#

Cos?

azure reef
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cos?

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what

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how cos can be angle

forest niche
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Phi then? It’s whatever man I give up

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This problem is slowly making me mental

azure reef
#

prolly that is better

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when sin is 0?

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literally, when blue part is absent?

calm shoal
azure reef
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channel is clearly occupied

forest niche
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When sin is 0 cos is 0 what am I missing

azure reef
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what

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@forest niche ok let do that way

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draw position of radius so that sin is 0

long shale
#

@calm shoal just break the vectors into components, You have 2 vectors, one of magnitude 353, and an amgle of 229.2, you need to get the x component and the y component, using the cos(a) = x and sin(a) = y

calm shoal
#

so it would be cos(229.2)=353?

long shale
#

have you reviewed what the component method is?

calm shoal
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not really lol

next jackal
#

@long shale what happens when one side of a triangle =0?

long shale
#

@next jackal are you asking, when your on the axis?

next jackal
#

Ohh sorry, I mistook you for that@forest niche guy

long shale
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@calm shoal

calm shoal
#

ooo

long shale
#

you can solve for the angles at the origin, use some trig and youll get the componets, do the same for B then add components

silver fable
#

Hi I have this problem I know how to find X but I also need to find the angle between A and B

Is it possible? anybody knows how can I get that?

long shale
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@silver fable what have you tried

silver fable
#

Its for programming purposes I tried to get the angle of OA and OB and subtract them but doesn't seem right

long shale
#

is OC is perpendicular on AB

silver fable
#

Yes it's always perpendicular

long shale
#

so how can you use that fact?

silver fable
#

Oh right I can make a right triangle with it!

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So I can easily get the angle between OC and OA and then after I got that I multiply it by two and I get the angle that BOA makes, is that it?

long shale
#

yes

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and are you good for x?

silver fable
#

Yeah I already solved for X it's basic pythagora but sometimes it gives me wrong answers when the arc is so small which I don't think is a problem with the math which brings me here for the second solution

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Thanks

neon sun
#

Hi I’m a little stuck on this problem! I’m not quite sure what I can do next and was wondering if I could get some help😅

upper karma
#

@neon sun ?

neon sun
#

The question is in the brackets. To put the expression in terms of a &b when a=sin(x/2) and b=cos(x/2). If you understand what I’m supposed to do, could you give me a hint as to what I should do next?

upper karma
#

@neon sun if you know the formula for sin(2x) and cos(2x)

#

use the same formula, but do sin(x) and cos(x) instead

#

as if it were x/2 + x/2

#

and expand

neon sun
#

I see. Thank you!

fickle sleet
#

Could 2-cos^2x/sinx not be simplified to 1+1-cos^2x/sinx?

#

Like it makes sense in my head but apparently its not correct

#

From here i could turn 1-cos^2x to sin^2x

#

Which makes the whole expression simplified to 1+sinx

#

The textbook just says cscx + sinx which makes no sense to me

versed river
#

Which makes the whole expression simplified to 1+sinx
this seems to be the part where you made the error

#

wait also

#

could you tell me

#

which parts are actually in the fraction

#

is it 2-cos^2x/sinx or(2-cos^2x)/sinx

fickle sleet
#

Sorry yeah the formatting is pretty awful

#

The latter

versed river
#

ok good, the error is where you went from (1+sin^2(x))/sinx to 1+sinx

#

can you tell me how you got that result?

fickle sleet
#

sin^2x = sinx + sinx

#

One instance of sinx cancels out with denominator

versed river
#

sin^2(x)=(sinx)^2

#

=sinx*sinx not sinx+sinx

fickle sleet
#

wait hold up right my bad

versed river
#

would still be wrong but

fickle sleet
#

but still though, that means (sinx)(sinx) right?

versed river
#

yes

fickle sleet
#

A factor can cancel with denominator right?

versed river
#

can you be more specific

fickle sleet
#

For example (x+3)(x+3)/x+3 = x+3

#

Since one factor cancels

#

so why not here?

versed river
#

for x!=-3 but yeah

#

because you have the one here

#

can you show me how that applies in this case

fickle sleet
#

Isn't every factor that is the same, has the ability to cancel? (3)(3)/3 = 3 for example

#

I can't think of a scenario where this doesn't apply

versed river
#

yeah its true but what you have is $\frac{1+\sin^2(x)}{\sin(x)}$

somber coyoteBOT
versed river
#

which part are you factoring out of the numerator

fickle sleet
#

sin^2x

#

Since it composes out of 2 sinx's

#

OH WAIT I see now that 1 prevents this from being simplified right?

versed river
#

$\frac{1}{\sin(x)}+\frac{\sin^2(x)}{\sin(x)}$?

somber coyoteBOT
versed river
#

that gives you $\frac{1}{\sin(x)}+\sin(x)$

somber coyoteBOT
fickle sleet
#

Right I see now

versed river
#

OH WAIT I see now that 1 prevents this from being simplified right?

#

yes

fickle sleet
#

I was about to make an analogy with (1+3^2)/3 for a second there and I caught myself

#

That clears it up thank you for pointing out the dumb mistake

versed river
#

no worries

fickle sleet
#

I get it now too with (1/sinx) + sinx

#

that's where the cscx comes from

versed river
#

👍

upper karma
#

csc(x) + sin(x) yEet

solar shale
#

How do I tell

silent plank
#

circles are congruent if they have the radii of equal lengths

solar shale
#

Oh ok then it’s not congruent because they would have to overlap

upper karma
#

no

#

did you read what ramonov said

sleek thistle
#

Am i correct here?

#

nvm

upper karma
#

Ababababababba

sleek thistle
#

Abababa

tawdry pivot
#

Abababababa

arctic vortex
#

can anyone help me with some geometry problems ??

upper karma
#

@arctic vortex go with them

cosmic pebbleBOT
#
Rule 1

The help channels are solely for help with math, so feel free to post your question. Asking whether you can ask a question or if anyone knows about some specific topic is unnecessary, so please try to avoid questions of that nature.

arctic vortex
#

ok

#

:) u are very nice

#

@upper karma

upper karma
#

First, is it a test?

arctic vortex
#

nope

upper karma
#

Ok good

arctic vortex
#

it is homework assignment

upper karma
#

Let me see

arctic vortex
#

my test is on august 8th

#

its the final exam

#

i have 15 problems but i only need help with like 6

upper karma
#

Okay yes it is a

arctic vortex
#

yay

#

how do i do this one

#

im confused

teal stag
#

You have angles and a circle. I would recommend going through the facts you have about angles and circles, and seeing what they tell you. You might not know which facts will be helpful, but if you go through them you'll have more info than before

arctic vortex
#

okay

#

i will do that

#

in the mean time can u check something else @teal stag ?

#

im confused on inscribed angle and central angle

teal stag
#

The boxes you have look good. "central" means it's at the center of the circle (which is A). "inscribed" means it's drawn on the circle itself (which D is)

arctic vortex
#

ohhhh

#

so it is correct

#

ok i thought that central meant the A

teal stag
#

good thinking!

arctic vortex
#

thank you :)

#

how do i make it so that its one of the answer choices

#

@teal stag

teal stag
#

2/9=169pi is an equation, and I don't think that's what you meant to write

arctic vortex
#

yes

teal stag
#

Both "2/9" and "169pi" are important values here, but what is the area (in terms of pi)?

arctic vortex
#

169* * 3.14?

teal stag
#

Let me rephrase. "2/9 = 169pi" is obviously false because the left side is less than 1 and the right side is over 400. What did you mean to write?

arctic vortex
teal stag
#

That's an equation which is false

arctic vortex
#

yes

teal stag
#

The area of the section of the garden isn't the equation "2/9 = 169pi", it's the number: "???"

arctic vortex
#

yes

#

but how do i find that number

teal stag
#

Let's break this down. What's the area of the whole circle?

#

I think this is something you already figured out. I just want to highlight the steps of the process.

arctic vortex
#

530.93

#

is the area

teal stag
#

That's approximately the area of the whole circle. If you just say "the area" you could confuse yourself as to when you'

#

re talking about the area of the whole circle and when you're talking about the area of the sector

#

The area of the whole circle is exactly $169\pi,\mathrm{ft}^2$

somber coyoteBOT
arctic vortex
#

yeah im talking about the sector area

teal stag
#

The sector area is much less than 169pi

arctic vortex
#

yes

teal stag
#

That's why I'm emphasizing the distinction

#

Now, what fraction of the whole circle is the sector/section of the garden? (this is also something you figured out)

arctic vortex
#

so its 2/9 of 169pi

sinful anvil
#

An area of the sector can be found by using the formula theta/360 ^ Pi * R²

teal stag
#

right. And when you have a fraction "of" a number, what do you do.

arctic vortex
#

multiply

teal stag
#

Right

arctic vortex
#

117

teal stag
#

so it's not "2/9=169pi"

arctic vortex
#

.98

teal stag
#

it's "(2/9)*169pi"

arctic vortex
#

ohhh ok

#

so its 118

#

rounded

#

wow u are smart

teal stag
#

You already had the pieces. I just helped you put them together

arctic vortex
#

yes thank you :))

teal stag
#

I have to go now, but if you have more questions, others here can likely help

#

I was happy to help, though

arctic vortex
#

okay

#

same i was happy for u to help me :)

#

because 2 * 3x-2 = 5x

#

x=4

#

and then 10 + 2 = 12

sinful anvil
#

I don’t even know vectors

#

They’re too confusing

arctic vortex
#

oh

olive solar
#

@arctic vortex are you asking for help with this question?

arctic vortex
#

yes

#

@olive solar is it 12?

olive solar
#

yeah

#

although id write it as 2*(3x-2) instead

#

when you write it as 2*3x-2, it looks like you mean 6x-2 rather than 6x-4

arctic vortex
#

yeah true

#

this be *

#

because 92 is a vertical angle

#

@olive solar

olive solar
#

are you certain angle RSQ = angle SQT and not RTQ?

#

look at the arcs formed by each angle

arctic vortex
#

oh yeah

#

92+50

#

180-142

#

38

#

38?

#

@olive solar

olive solar
#

yes

arctic vortex
#

is 70 correct @olive solar

#

because i think its like a triangle

olive solar
#

how did you decide on 70?

arctic vortex
#

180-110

olive solar
#

so the portion of the segment SR that is also within C is a chord, yes?

arctic vortex
#

yea

olive solar
#

and QS seems to be tangent to the circle

#

so here you would be using the tangent chord angle thm

arctic vortex
#

ohh

olive solar
#

the question doesnt really confirm whether that's a tangent though so GWbruhThonkNoHands

arctic vortex
livid sequoia
olive solar
#

@arctic vortex do you know how to find the angle of an internal angle given the measure of its arc

#

@livid sequoia do you know the classification of a rhombus

arctic vortex
#

i think square is a rhombi

#

parallelogram, trapezoid, rectangle

#

i think

livid sequoia
#

a rhombus has 4 congruent sides

#

so its not A :L?

olive solar
#

can c be considered to have 4 congruent

livid sequoia
#

No

#

So its B C and F

olive solar
#

yep

livid sequoia
#

thank u

olive solar
#

you are able to find angle C given everything in the diagram@arctic vortex

#

once you have angle C and angle A, angle B can be found based off the properties of a triangle

arctic vortex
#

64?

olive solar
#

howd you get 64?

arctic vortex
#

47+69

#

180-116

olive solar
#

remember, C is an inscribed angle

arctic vortex
#

yeah

#

idk

#

cna u tell me >

#

?

olive solar
#

i could tell you the solution but i won't

#

look at how to get the measure of an inscribed angle from the arc it forms

arctic vortex
#

o

#

wait

#

i think i know

#

wait no i dont

olive solar
#

do you have a textbook?

#

id recommend that you go through either that or get some proficiency with google

#

you could search "inscribed angle theorem" and youll get what you need here

arctic vortex
#

o i got it

#

ty

#

i finished it a while back actually lol

sly belfry
#

how can I retrieve the general formula of a transformation in the complex plane by having the matrix form?

#

I'm used to doing it the other way around

#

even better - I have the general expression in terms of x and y

#

I think I'll plug in i in the y value?

dark sparrow
#

wym matrix form

sly belfry
#

well

#

I have general expression f(x, y) of a plane transform

#

and i want it to be f(z) = cz + d

#

and I forgot how to do it 😐

dark sparrow
#

how do you know it's even expressible in that form tho

#

like

surreal bolt
#

Um, can you figure out what the transformations are that get you from start to finish?

dark sparrow
#

it need not be

#

bc you're being overly general rn

surreal bolt
#

(agrees with ann)

sly belfry
#

ok, here's the exercise

dark sparrow
#

can you maybe be more specific

sly belfry
#

so I know f is a translation after a transformation

#

I suppose it is an homotety

#

because the ratio is not 1

#

and it's given that f(x, y) is a transformation, if that helps...?

dark sparrow
#

uh

#

well i guess you could write $f(x,y) = \mat{2\3} + \mat{\sqrt{15}/10 & -\sqrt{10}/10 \ \sqrt{10}/10 & \sqrt{15}/10} \mat{x \ y}$

somber coyoteBOT
dark sparrow
#

for the actual "matrix form" of the function

sly belfry
#

(yes, that's what I did, but it's not terribly useful)

surreal bolt
#

[a, y] * (2 x 2 rotation matrix) + (x_0, y_0) = (xfinal, yfinal) ? 🙂

dark sparrow
#

and that makes it more clear that this actually CAN be expressed as an affine map on C

surreal bolt
#

sorry I got the order wrong

dark sparrow
#

$f(z) = 2+3i + \frac{1}{10}(\sqrt{15} + \sqrt{10}i)z$

somber coyoteBOT
sly belfry
#

hmm

#

how?

#

y = i?

dark sparrow
#

multiplication by $a+bi$ considered as a linear map on $\bR^2$ has the matrix $$\mat{a & -b \ b & a}$$

somber coyoteBOT
sly belfry
#

oooh

#

actually pretty straightforward

#

if I want to calculate the image of any vectorial eq.

#

in this case, something like (0,0) + (a, b)

#

is it okay to plug in z = a + bi in the f(z)?

dark sparrow
#

i mean...

#

yes

sly belfry
#

sorry ann

#

i promise I'm way better in some other stuff 😦

nocturne dove
little osprey
#

What have you tried

nocturne dove
#

Well its a proof so all I've really done is write the givens lol

#

tried looking online for some help

#

didn't really know what to look for

little osprey
#

Is this a question from your teacher or

nocturne dove
#

ye

little osprey
#

ah ok

#

Well

#

@nocturne dove Anything?

nocturne dove
#

Nothing unfortunately, Im asking around with my friends but none seem to remember

little osprey
#

Have you used any circle theorems

nocturne dove
#

I'll go check some more out

little osprey
#

Hint: right angle

nocturne dove
#

?

#

going on a whim here

little osprey
#

Join AP and BQ

nocturne dove
#

ah

little osprey
#

Anything?

nocturne dove
#

sorry nothing's clicking for now, but thanks though!

little osprey
#

Lol

#

Well you could stay here

#

and I could try and guide you to the right direction

nocturne dove
#

that'd be great lol

little osprey
#

Well what happens when a radius is drawn to a tangent point

#

I want to help, but you have to put some effort in :/

nocturne dove
#

Yeah, sorry man, I not too good at this as you can see

#

I remember something about it being perpendicular or something like that

little osprey
#

yes

#

right angled

#

so which angles would be right angled then?

nocturne dove
#

I would assume these four

little osprey
#

Ok, correct, but remember AB is also tangent

nocturne dove
#

Sorry for delayed answers Im just looking at definitions at my other screen to piece things together

little osprey
#

No worries dude take your time, I understand

nocturne dove
#

well I did find this

#

is it applicable to this or na

little osprey
#

PAM and QBM will form right angles as well?

nocturne dove
#

now that I wouldn't have gotten

little osprey
#

Because they are tangent

nocturne dove
#

yep

#

ah

little osprey
#

Do you understand the reasoning

nocturne dove
#

a bit but could you explain why it being tangent forms right angles

little osprey
#

The proof?

nocturne dove
#

actually

#

nah its ok

#

I think I can handle the rest with my friends seeing as theyre awake now

#

thanks for all your help bro

#

I really appreciate it

little osprey
#

No worries dude, sorry I couldnt explain it well enough

nocturne dove
#

nah its alright Im just not good at these things

upper karma
#

nah its alright Im just not good at these things
@PrivateFishy#2029
What's the problem??

#

Could i try to help

little osprey
#

He left the server

#

I did try and help him

#

it was a geo problem

sleek thistle
#

can i get some help?

long shale
#

do you know what a sine or cosine is?

sleek thistle
#

so with part b, would y be tan(50)=x/y or cos(50)=y/12?

long shale
#

ya

sleek thistle
#

or can it be both

long shale
#

so its both, since x = 12sin(50)

#

they are equal

sleek thistle
#

okay yeah i just wanted to know if one of them was more

#

right i guess

#

i know it’s easier with cos so i’ll just put that

long shale
#

👍

sleek thistle
#

is this correct?

neon sun
#

I don’t think you proved triangle AEC=DEB. If I remember correctly from my geom, that should be your last statement if you are trying to prove it.

sleek thistle
#

ooh yeah you’re right

upper karma
#

Pretty sure that's a typo

sleek thistle
#

yeah i meant to put AEC congruent to DEB

#

oh yeah i also need help with a trig problem

#

hold on

#

for c would i be right in saying i can’t use the tangent ratio?

#

and sorry for the bad hand writing, i could clarify if needed

glacial haven
#

no

#

you can use tangent after solving for one of the unknowns

sleek thistle
#

oh wait let me clarify the question

#

the question says would you be able to use the tangent ratio to solve part a-b

glacial haven
#

tan(50)=12sin(50)/12cos(50)

#

you can

sleek thistle
#

so if you use tangent to solve a you can get x?

#

wouldn’t that give you tan(50)=x/y?

glacial haven
#

yeah

#

and x=12sin(50)

sleek thistle
#

but when i put it into my calculator it gives me x=1.19175359y

#

so wouldn’t you need at least one value before solving with tangent?

glacial haven
#

if you use tangent you're gonna have to use cosine and sine

#

but its still possible

sleek thistle
#

oh okay

#

i just think the question is asking whether we can use tangent for both before using anything

glacial haven
#

do you have the question?

sleek thistle
#

yeah

#

they should’ve clarified more i think

glacial haven
#

uh that question isnt clear

#

but you most definitely can use the tangent ratio

sleek thistle
#

yeah i’m just gonna ask my teacher

#

“Are you able to solve a or b with the given info using tangent as opposed to how you actually did it? That’s what the other student is claiming.”

#

i think i’d be correct right?

#

cause you can only use tangent when you solve one of them with sine or cosine

solar shale
#

Would that be considered an inscribed angle or no? Bc if so then woudlnt 1=21.5?

#

Or would I do like 92-43=(1)

silent plank
#

neither

solar shale
#

I honestly don’t know what I do I thought I was an inscribed

silent plank
#

1 isn't at the circumference

#

look up something like
outside angle theorem for circles

#

which can be derived from inscribed angle theorems

solar shale
#

Got it 24.5

#

92-43 then divide by 2

#

?

silent plank
#

yes

solar shale
#

Thanks also I need help with this question could you like tell me with theorem or what rule I use so I can look it up

silent plank
#

cyclic quadrilaterals and alternate segment theorem

solar shale
#

Ok thank you

silent plank
#

whoops i mean inscribed angle theorem / central angles instead of cyclic quad

solar shale
#

Ok

#

Oh so the answer would just be 85

silent plank
#

yes

shrewd wasp
#

Any idea to solve acos(x)+bsin(x)=c

upper karma
#

Looking for x?

shrewd wasp
#

yes

#

I found an identity

upper karma
#

Ok

#

Epic

empty hornet
upper karma
#

What's the general formula for the volume of a prism?

little osprey
#

Annulus

#

or how you spell it

empty hornet
#

Its just A x H

upper karma
#

Ye

little osprey
#

How would you go on calculating the volume

upper karma
#

You have both A and H in this case

little osprey
#

oh

#

he does

empty hornet
#

yeah that would equal 910cm

#

cubed

upper karma
#

I thought the radii were given too

empty hornet
#

sadly not

#

thats why im confused

upper karma
#

That's the correct answer

empty hornet
#

that should make more sense then

#

i though it meant to calculate the actual opening

upper karma
#

It has to be the right answer

#

Because that's the only volume you are able to calculate

empty hornet
#

yeah

arctic vortex
#

ok so im taking my geometry finals soon and i want to ask if there are any tips u guys wanna give me

upper karma
#

Draw labeled and precise diagrams

#

Use various colors

little osprey
#

Also

#

Have fun

silent plank
#

don't forget about the ambiguous case with sine

little osprey
#

Good tip

charred zephyr
#

hey can someone give me a little hint.
ABCD is a parallelogram and I is midpoint of line BC
Line HD is perpendicular to AI with H a point of AI
Show that CD = CH
here's the sketch i have drawn:
idk what should i use, but i think it'll be about angles. i tried to find similar triangles but couldn't.

#

maybe proving HCD is isoceles

little osprey
#

shall we chase angles or shall we not?

charred zephyr
#

idk

#

maybe$

#

so we can get HDC = DHC

little osprey
#

yeah maybe, I'll have a go

#

I cant think of anything rn...

charred zephyr
#

me 2

#

😦

livid sequoia
little osprey
#

@livid sequoia What have you tried

livid sequoia
#

I confused about the 2 and 8

little osprey
#

Do you know what the pythagorean theorem is

livid sequoia
#

yea

little osprey
#

and why did you subtract?

charred zephyr
#

apply pythagoras two times

livid sequoia
#

to find the other leg fo AD

little osprey
#

why would you add

#

You have the hypotenuse and leg

livid sequoia
#

you told me why did I subtract

#

o

little osprey
#

I said why did you subtract because you didnt square them

charred zephyr
#

you must square sqrt(2) and 1 and then substract

livid sequoia
little osprey
#

yes but remember

charred zephyr
#

yes

little osprey
#

its c^2

#

so right now you have

#

c^2 = 9

#

Do you get what I mean

charred zephyr
#

add a last step

livid sequoia
#

i dont know what to do next

#

OH

little osprey
#

yes

#

youre done

livid sequoia
#

thank u

little osprey
#

no worries

upper karma
#

@charred zephyr I'll take a look at your problem layer, Imma @ you if I find something interesting

little osprey
#

Hell yeah HoboSas

upper karma
#

Ok that probably took too much time

#

||Let G be the midpoint of side AD||

#

||For Thales theorem we have that DM=MH (you can also check this noticing that triangles DMG and DHA are similar and their "ratio of similarity" is 1/2)||

#

||Consider now triangles DMC and CMH, they are congruent for SAS (DM=MH, right angle and a shared side). In particular CD=CH.||

#

@charred zephyr

lusty quest
little osprey
#

@lusty quest Heron's formula

lusty quest
#

ahh ok thanks

little osprey
#

Have you heard of it?

upper karma
#

definite integrals

lusty quest
#

yes, i just havent done this in a while

little osprey
#

Oh wait

#

Distance formula

#

then herons

rigid thunder
#

You can measure area of planar object by weighing it on scales: cut it out of some tin (to scale, for example in cm), weigh 1 square cm piece of tin, then weigh the triangle, and you get numerical value for the area from weight