#geometry-and-trigonometry

1 messages · Page 330 of 1

upper karma
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Pls help me

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Someone

upper steppe
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With what?

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@upper karma

upper karma
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Proofs

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I’m about to cry

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It’s so difficult

upper steppe
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I hate proofs lol

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What are you working on?

upper karma
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Idk it’s jusf stupid proofs

slate blade
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Diameter = 26, therefore circumference = 26pi.
y= aSin(bx-c)+d
b=2pi/26pi
b=1/13
The y transfer =+13

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Triangle proofs or induction

upper steppe
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@upper karma send me pic maybe I can help

upper karma
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Ok

upper steppe
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I’m still learning though

upper karma
slate blade
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@upper karma my best suggestion is just to get a piece of paper and “redraw” all of the figures with the given/derived information

upper karma
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I fried

upper steppe
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@upper karma can I see the choices?

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Like click the box so I can see the options

upper karma
upper steppe
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What the actual huh?!?!

slate blade
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First do AE is equal in magnitude to EC

upper karma
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It’s impossible

slate blade
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Since it is give. That DB bisects it

upper steppe
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That’s geometry right?

upper karma
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Ye

slate blade
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Yeah. Trying to prove congruency using ASS or SSS formulae

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Or any of the other combinations

upper steppe
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The x and t threw me off

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Y*

slate blade
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X and y and stuff are there as placeholders

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You’re meant to fill it in with the letters from the triangles

upper karma
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Nvm

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I got it

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100%

upper steppe
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Xyz is congruent to tuv

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I think

upper karma
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Less go

slate blade
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Epic

upper karma
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Gn

upper steppe
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What was it?

upper karma
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Not sure

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I just did it

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And it says it’s right

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So pce

upper steppe
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What was the answer tho...

slate blade
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Lol

upper steppe
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Please help

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I’m to stupid and tired for this

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I think it’s 38

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It was 38 now I don’t get this one at all

west basin
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sounds good

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oh lol

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well you are given angles on a line

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so they add up to?

upper steppe
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I’m sorry if I seem weird I been in school since 7:20 and been doing hw since I got out at 2:20 and now it’s almost 11 my brain is dead

west basin
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its cool

upper steppe
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180

west basin
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yes

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so 180 - 114

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is the red angles measure

upper steppe
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Huh?

west basin
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angles on a line add up to 180

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so the measure of the red angle will be 180 - 114

upper steppe
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66

west basin
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yes

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so both red angles will be 66

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so add them and subtract from 180

upper steppe
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48?

west basin
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yeah

upper steppe
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Fml I got another one

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And it feels like I’m about to faint

west basin
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yeah

upper steppe
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I have 168 questions estimated

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Left then I’m done

west basin
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sick

tender prawn
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168 jeez

west basin
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were you assigned them for one assigment or did you just slack off

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and wait til the last minute

upper steppe
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My dumbass slacked off

west basin
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yeah there ya go

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played yourself

upper steppe
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This was assigned for last and this week

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And it’s due Sunday

west basin
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if you just did a small portion everyday it would of bene a lot better and your understanding would probably be better

upper steppe
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Yup

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I’m kicking myself rn

tender prawn
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lol im doing that too

upper steppe
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I can barely remember something for 2 seconds rn

tender prawn
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i had 2 weeks to do these 8 problems but ive spent the whole entire day bashing them out

upper steppe
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Bro I was studying for my algebra eoc instead

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Cause I tested Tuesday

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Instead of doing this

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I should’ve done this instead of studies

tender prawn
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ig thts fair

upper steppe
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Brb ima to get water

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I’m back

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Can someone explain this to me?

tender prawn
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just like

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count the side lengths

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u can use side angle side cuz u know one of them is a right triangle

upper steppe
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They both are

tender prawn
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oh yeah both oops

upper steppe
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Your method is so much easier

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I was trying to calculate the points and get the measurement like that

tender prawn
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lol

upper steppe
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Apparently I can’t count 😦

tender prawn
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rip

upper steppe
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Can you pls help me?

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I been on it for a hour

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And my smart score is 61 and I need to 90

pure cape
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I dont think we are supposed to help you with passing test

upper steppe
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It’s not a test....

pure cape
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Then why should there be score

upper steppe
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I don’t think a teacher would give a test at 11:49 pm

upper steppe
pure cape
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And also, help you with what?

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Could you post the problem?

upper steppe
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Scroll up I need a better way to solve these

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Cause for some reason even counting them i get it wrong

pure cape
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You need help with the picture above right?

upper steppe
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That’s the type of questions I’m getting yes

pure cape
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Well so basically we need to prpve it by using sides, since we dont have any angles

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The fastest way i could think of us sss

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If you do intend tp use sas with the angle being the right angle, then you must prove that they are both right triangle

upper steppe
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I don’t need fast

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I need accurate

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Can’t you just tell a triangle by the angles (looking no measurement)

pure cape
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So do you know how to calculate the distance between two points on a graph?

upper steppe
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Yeah distance formula

pure cape
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Like you said, you need accurate not fast

pure cape
upper steppe
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D=(x2-x1)^2 + (y2-y1)^2

pure cape
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Sth is missing innit?

upper steppe
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Huh?

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If you mean squared

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I don’t have that symbol

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On my@ketboard

pure cape
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Yes

upper steppe
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Keyboard*

pure cape
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There should be a square root

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Ok so can you calculate the distance between point E and F for me?

upper steppe
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8-9

pure cape
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What?

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Use the formula

upper steppe
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I did

pure cape
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Point E(0;8)
Point F(9;-3)

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So whats the distance

upper steppe
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8.94

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Round of to 9

pure cape
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You did something wrong

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Try again

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Tell me x1 and x2

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And y1 y2

upper steppe
pure cape
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Whats 11^2

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What does it equal

upper steppe
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121

pure cape
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So 81 + 121 is?

upper steppe
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202

pure cape
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For the record (-11)^2 isnt -1

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Do you know why?

upper steppe
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Yeah I know why

pure cape
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And there should be a square around the -3 -8 on the second line

upper steppe
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Just ain’t think right I been doing school since 7:20 am

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Gotta go slower with me

pure cape
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Sure

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So (x1 - x2)^2 + (y1 - y2)^2 = 202

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Right?

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Now take the square root of that

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Which is sqrt(202)

upper steppe
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14.21

pure cape
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Which is arppox. 14.2

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But next time when doing math, try not to approximate

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Just keep it as sqrt(202)

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Ok so now we know that EF = sqrt(202)

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Can you find BC?

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Write out x1 x2 y1 and y2

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Then plug it in the formula

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Show me your work ok?

upper steppe
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Same thing

pure cape
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Good

upper steppe
pure cape
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Ok so we proved ef = bc

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Now can you do that for the other two sides?

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With the same method?

upper steppe
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Yes thank you

pure cape
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Yw

upper steppe
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@pure cape just finished that assignment

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Now it’s time for the most hate proofs

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Oops sorry

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Didn’t mean to tag

pure cape
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its ok

remote sierra
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I need help with a problem

green osprey
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hey i need help with some geometry

dark sparrow
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y'all should post your questions right away instead of waiting for someone to show up

green osprey
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oh

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okay so what is a perpendicular bisector and how do i calculate one with two perpendicular bisectors

silent plank
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a perpendicular bisector as the name suggests is a line that is perpendicular to another line segment and bisects it

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the latter part of the question is unclear

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perhaps post the question exactly as worded

green osprey
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the segments are in a triangle

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the question is In Triangle ABC DZ, EZ and FZ are perpendicular bisectors. If AZ = 76 and BD = 51 and ZE = 23, what is the length of AB and ZC.

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this is the triangle

placid bone
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ah

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you can use vectors for this if you know how to

green osprey
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dont know

placid bone
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it's quite simple if you do use vectors

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ah

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in that case

silent plank
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DZ being a perpendicular bisector here means that it bisects AB,
i.e. BD = DA

upper karma
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Are calculus proves based on geometry

placid bone
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wait sike

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you can't use vectors for this

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you can prove that the altitudes of a triangle are concurrent with vectors stho

green osprey
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idk man

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we havent went over vectors yet

upper karma
silent plank
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ignore the stuff about vectors

green osprey
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i still dont know what ZC is lol

silent plank
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apply pythagoras a few times

green osprey
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tried that and i ended up with irrational numbers

silent plank
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and why would that be an issue?

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are you implying that lengths can't be irrational?

green osprey
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its on delta math and usually its supposed to be rational

upper karma
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...

silent plank
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supposed to be...

green osprey
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it should work

upper karma
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show calculations

silent plank
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perhaps show your work

green osprey
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ok

silent plank
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you could even just apply sas congruency

green osprey
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wait im stupid

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its 76

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wait what

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so far i figured out bz = 71and AD= 51 and i know az = 76, ZE = 23, and BD = 51

silent plank
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how are you getting BZ as 71

green osprey
silent plank
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i can't read that second line

green osprey
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76^2 = 51^2 + DZ^2

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DZ = 5*sqrt(127)

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sqrt((5*sqrt(127))^2+51^2)=BZ

silent plank
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and you won't get 71 from that

green osprey
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oop my bad 76

silent plank
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i also mentioned a bit later that you could also just apply SAS congruency

green osprey
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yea but then i would need to know ZE and EC

silent plank
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not really no

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you're told certain segments are perp bisectors

green osprey
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yeah

silent plank
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DZ is common,
DB = DA since DZ is a perp bis
<BDZ = <ADZ = 90°
for congruency of ADZ and BDZ (by SAS) hence AZ = BZ
similar idea for the other triangles

green osprey
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wait what

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how can db = ab

silent plank
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whops typo

green osprey
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.-.

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i knew that

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they both were 76

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i need to find zc

silent plank
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similar idea for the other triangles

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do exactly the same thing

green osprey
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i dont have ze though

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or ec

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or BC in general

silent plank
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your told what ZE is not that it really matters

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its a common side in the bottom two triangles

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its also a perpendicular bisector

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and congruency can be proven in the exact same way as the other triangles earlier

green osprey
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but i need to find either ZE and EC or FC and ZF too prove SAS right

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sorry if i sound stupid i still havent slept

silent plank
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use exactly the same ideas i did for the two triangles above

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ZE is common in tri BEZ and CEZE

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BE = EC since ZE is a perp bis

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right angles etc

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congruency SAS etc

green osprey
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ohhhhh

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i get it

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so 76?

silent plank
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yes

green osprey
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hopefully i dont fuck this up

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im almost at a c

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POGGERS

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the homework automatically grades

earnest fjord
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Show that the vertices A(-2,0), B(0, 2sqrt3), C(2,0) are vertices of an equilateral triangle

dusky surge
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What have you tried?

earnest fjord
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My current best guess is starting to find the lengths of the sides

dusky surge
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Good start!

earnest fjord
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And then compare AB = AC = BC

dusky surge
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That's actually a very good approach.

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Do you know how to find the distance between 2 points?

earnest fjord
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Yes, formula

dusky surge
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Then it's going to be easy as you just sub the points into the formula

earnest fjord
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I'll try that

dusky surge
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Good luck!

earnest fjord
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Thank you

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The length of AC is 12 cm. CD is tangent to the circle at D. The radius is 6cm. What is the area of the shaded region?

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With this one I'm quite lost as it's one of the harder things for me

earnest echo
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Do you know that tangent makes right angle with radius??

earnest fjord
earnest echo
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Yes

earnest fjord
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I have a pretty good idea about how this would work now

earnest echo
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👍

earnest fjord
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Find sector first and then the entire triangle

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and subtract sector from the triangle area

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to get shaded region

earnest echo
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Yes

earnest fjord
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Wait so

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Because that's right angled we can just use pythagora's to find the third side?

earnest echo
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Third angle??

earnest fjord
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third side*

earnest echo
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Yes

hybrid quiver
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I've tried using the 15 tangent formula and then doing Poly transforms

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Is this optimal?

gray whale
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Could someone be so kind to explain D) I don’t know how to add them to get the result in 2nd image

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Please @ me

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If you respond. Thanks in advance 🙂

main lintel
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@gray whale Can you write the question here as text with substituted values

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I have one solution. It seems kind of obvious that you have to try to split S2 into two parts, by the sin(a-b) = sinacosb - cosasinb rule

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This gives you S2 = 2*sin200t*cos(0.2) - 2 *cos200t*sin(0.2)

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Now ST= S1+S2 = (3+2cos(0.2))*sin200t - 2sin(0.2)*cos(200t) [1]

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Where 5*cos(0,2) and 3+2sin(0.2) are some plain numbers.

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Now, by the same formula above, just in reverse you have that these two numbers:
5cos(0.2) and 3+2*sin(0.2)
can be transformed in such a way that they form the terms of an analogue sinusiode:
A*sin(x-y) = Asinxcosy - Acosxsiny

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Comparing this with equation [1] above we have that:

x = 200t
Acosy = 5*cos(0.2)
Asiny = 3+2*sin(0.2)
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You can substitute A from first into the second to get: tan y = some number, which gives the basic solution for y as 0.08 and an infinite number of them y=0.08 + k*PI

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Put that into the first equation.
You get two sets of solutions,
A=4.916 phi=0.08+2kPI
A=-4.916 phi=0.08+PI+2kPI
Because the negative amplitude just shifts the phi by PI, the final equation is the same for both solutions
4.916*sin(200t-0.08+2kPI)
For some reason they just took the solution with k=0 so
4.916*sin(200(t - 0.08/200))

upper karma
#

Explain why the distance point P travels is the same as the angle of revolution (measured in radians) of this wheel.

main lintel
#

P is travelling along the arc of this circle, so the distance it travels when circle rotates by angle of revolution is equal to the length of the arc respective to that angle.

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The length of the arc is length = radius*angle_in_radians=1 [ft]*angle_in_radians= angle_in_radians [ft]

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@upper karma

upper karma
#

thanks

main lintel
# hybrid quiver Help?

First, I think there are 7 solutions strictly between 0 and pi/2. 7 solutions between -pi/2 and 0, and 0 as the 15th solution.

#

There might even be 8 intersections on each side plus 0, so 17 in total from -pi/2 till pi/2

hybrid quiver
main lintel
#

I don't get it what you did there

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What is the Poly treansform? @hybrid quiver

hybrid quiver
#

k=sqrt(1/m) @main lintel

hybrid quiver
#

@main lintel im changing the polynomial such that it has roots of 1/tan^2(x)

main lintel
#

@hybrid quiver How you got the formula for tg 15x, have you manually did the steps or you have some table?

hybrid quiver
#

the coefficients are 15 choose n @main lintel

main lintel
#

Aha, I see this

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@hybrid quiver After plugging in that, you got a polynom of 7th degree

hybrid quiver
#

Correct, it cancels out

main lintel
#

And you concluded that the wanted sum is the "second term coefficient/leading term coefficient" of the polynom

#

by Viete's formula

hybrid quiver
#

yessir

main lintel
#

It is a pretty interesting and very hard problem

hybrid quiver
#

5/78 is incorrect!?

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@main lintel can you recheck my work? it's wrong!

main lintel
#

I'm still not sure about the sqrt 1/k swap.

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Other things seem reasonable

hybrid quiver
#

It's by polynomial transformations

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the inverse function 1/k^2

main lintel
#

I mean, seems reasonable, but too late to comprehend it 100% 😄

hybrid quiver
#

Here's what I watched

main lintel
#

After the first step you have a polynom equation
P(u) = 0 where u=tan(x).

hybrid quiver
#

@main lintel did you watch the poly video?

main lintel
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No

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Polynom is just a function

hybrid quiver
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yes

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thanks to the legendary David Altizio

west basin
#

light theme PepeHands

hybrid quiver
#

@west basin 🤣

main lintel
#

If we have f(x) and we do x=g(y), and if g is bijection on the observed range, we have f(g(y)). Then the numbers x1, ..., xn that are the nullpoints of the old function have the respective y1=g-1(x1), ..., yn=g-1(xn) that are the nullpoints of the new function.
Because f(g(g-1(x1))=f(x1)=0

hybrid quiver
#

no, it's just inverted dark theme!

#

🇩🇯 🦋 👨

#

djmothman

#

aka djmathman

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aka David Altizio

upper karma
#

A carousel moves in a counterclockwise direction. It makes one complete revolution every 16 seconds. Han is sitting 11 feet from the center of the carousel. Here is a view of the carousel from above.

Based on the view from above, write an equation describing Han's vertical position v, in feet, relative to the center of the carousel t seconds after the carousel starts moving.

mild anvil
#

can someone help with my trig hw

slate blade
#

@upper karma you get a cos eqn

#

[
v=-11 \cos{(\frac{\pi}{8} \times t)}
]

somber coyoteBOT
upper karma
#

k thanks!

slate blade
#

I think at least. I'm not that smart either

#

@mild anvil you get 2 solutions from this right

mild anvil
#

i thought it was 4

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i tried 2 solutions but it kept saying to was wrong

slate blade
#

Well do you have your working?

#

[
x=\frac{\pi}{3}, \frac{2\pi}{3}
]

somber coyoteBOT
mild anvil
slate blade
#

oh shit u right double angles my bad

#

yeah it's 4 solutions

mild anvil
#

i’m rlly struggling with double and half angle identities bc our teacher didn’t teach us 😢

slate blade
#

ok so for your answer, it's 4 answers with the following

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basically all variations of 60 degrees

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so pi/3, 2pi/3, 4pi/3, 5pi/3

#

I think if I converted right sorry I'm kinda rusty as well

#

but here I'll give you a crash course on double angles if you want

mild anvil
#

omg thank you i love you

slate blade
#

but was the thing correct?

mild anvil
#

yes

slate blade
#

boom shakalaka

#

ok so now onto double angles

mild anvil
#

i’ve been stuck on it for so long 😭

civic crown
#

hi can i have help

mild anvil
#

can you help me with the rest of my hw?

slate blade
#

you basically know the three basic angle identities sin cos and tan

#

lol sure

mild anvil
#

yayyy

slate blade
#

let's finish the hw before the magic lesson

mild anvil
#

okie

#

everyone in this server is rlly smart i’m jelly

slate blade
#

empty set I think

mild anvil
#

i tried it it was wrong

slate blade
#

bruh what

mild anvil
#

yea i thought it would be that too but it’s not

slate blade
#

hmMMMMM could it be a typo?

#

oh wait no it's 3tan not 30

#

sorry but could you send screenshots instead of images its kinda hard to tell

mild anvil
#

yea gimmie one sec

slate blade
#

ok so here are the answers:

#

pi/6, 5pi/6, 3pi/2

mild anvil
#

dang i got it wrong cause it wnted it in degrees 😦

slate blade
#

oh lol whoops my bad

mild anvil
#

its ok

slate blade
#

sorry too used to workin gin rads.

mild anvil
#

its giving me another chance

slate blade
#

it's 30, 270, 150

#

hopefully

mild anvil
#

no its not that

slate blade
#

bruhhhh

#

wait I just realised solving for sin is not equal to secant

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I am so sorry

#

I ded today

mild anvil
#

its ok you can still give me the right answer for it. its giving me another chance

#

if you want to you dont have to

slate blade
#

0, 120, 240

#

Interval wise, [x,y) means that it doens't include y right

mild anvil
#

wow you're so smart

#

i wish i had the talent

slate blade
#

lmao you're overestimating me

#

but let's complete the quesitons

mild anvil
#

okie

slate blade
#

uhhhhhhh have you tried empty set on this one

#

from memory I did one similar and it didn't have an exact answer

mild anvil
#

yea its wrong

#

did you leave 😦

pure cape
#

try to do it slowly

slate blade
#

no I'm still alive I'm just confuse d

pure cape
#

divide by 5 on both sides, and consider a formula for theta

mild anvil
#

oh ok 🙂

slate blade
#

shouldn't there be multiple answers is what im considering

mild anvil
#

yes because its a set

pure cape
#

eventually you get something like (pi/4 + kpi)/3

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for all integers k

slate blade
#

cuz if so, it's just pi/4 and someother thing

pure cape
#

and now apply that to the interval [0:2pi)

slate blade
#

[0:2pi[

mild anvil
#

it gave me 6 different answers

pure cape
#

yes

#

there should be 6 different answers

#

for k from 0 to 5

placid bone
#

yep

#

solid

slate blade
#

lit

mild anvil
#

like i plugged in 2 answers but it said that was wrong and gave me 6

pure cape
#

since when k is 6, it exceeds the condition [0;2pi)

mild anvil
#

but i got it wrong

pure cape
#

what are your answers

#

and show me how you got it

placid bone
#

if you just think about it, tan3x just compresses the graph by a factor of 3

mild anvil
#

it went away

pure cape
#

what went away?

#

how can your answers go away

slate blade
#

they don't love you anymore

#

ok did you get

#

pi/12, 5pi/12, 3pi/4, 13pi/12, 17pi/12

#

wait I can use greek keyboard

mild anvil
#

like the correct answers went away because i clicked give me a similar one cause i got it wrong

#

yes rhats what i got but i got it wrong so it gave me another problem

slate blade
#

βρθη

pure cape
#

you're missing an answer

#

a solution, to be more exact

slate blade
#

isn't the next one 25pi/12? so out of its domain?

pure cape
#

what happens if k=5?

#

doesnt seem like it goes out of the domain

slate blade
#

wait no I forgot to type it lol

#

7pi/4

#

I just skipped it my b

#

alright what's the next question

mild anvil
slate blade
#

same panic different disco

#

I'll type it correctly this time watch me

#

π/12, 5π/12, 3π/4, 13π/12, 17π/12, 7π/4

#

I hope that's right

pure cape
#

basically same stuff, i think you should let luna do it first before giving out the answers

#

or try to explain

slate blade
#

good point

pure cape
#

giving out the answers is more of harming the person than actually helping them

mild anvil
#

it was correct thank you

slate blade
#

do you understadn how it is don

#

e

#

loona

mild anvil
#

no i dont 😦

placid bone
#

eek

#

when is tan 3x=1

mild anvil
#

could you explain

pure cape
#

like i said

slate blade
#

that ain't good

pure cape
#

its better to explain

placid bone
#

that's essentially what it's asking

mild anvil
#

like ive never learned it my teacher never taught us

placid bone
#

alright

#

so

slate blade
#

trig time

placid bone
#

when is tan x=1

#

from 0 to 6pi

pure cape
placid bone
#

and then divide your answers by 3

pure cape
#

thats a bad teacher

mild anvil
#

i know she sucks i hate her

pure cape
#

oh well

slate blade
#

or is it they taught you but did it really badly

mild anvil
#

but i cant blame her its because of corona

upper karma
#

Which angles are represented by the same point on the unit circle as \small \frac{\pi}{4}? Select all that apply.

mild anvil
#

no like she never taught us

upper karma
#

really need help with Trigonometric Functions

pure cape
#

this channel is occupied

#

try a different channel down at math-help

slate blade
#

lmao trig is one of the trippiest topics if you aren't taught well

upper karma
#

Virtual school while doing math isn't helping

placid bone
#

luna do you need the answers now?

slate blade
#

@upper karma try adding and subtracting pi, 2pi, etc. and doing pi/ (pi/4) etc. You'll get a ton of answers

upper karma
#

alr

mild anvil
#

she was like ok we dont have enough time so just try to learn it on your own

#

and she didnt give us notes or anythong

placid bone
#

@mild anvil what you basically do is just find when tan x=3 from [0, 6pi], then divide answers by 3

slate blade
#

and you change the domain to 6pi because it's 3x and 3*2pi = 6pi

#

orrrrrr you can also cheese the problem

#

by graphing it

mild anvil
#

i tried graphing it but like idk what im supposed to be looking at

slate blade
#

u use desmos?

mild anvil
#

no i use mathway

slate blade
#

that's not a tan function m8

mild anvil
#

yea im on a new problem

slate blade
#

ah ok can I see the question?

mild anvil
#

yea sure

slate blade
#

so I'll teach u the graphing way first, then the normal way

mild anvil
#

ok thank you

slate blade
#

take a look at your graph right, you're technically graphing 2 functions.

#

y=cos(2theta)

#

and

#

y=-sqrt(3)/2

#

just that they equal at points y right

desert vortex
#

Arent you suppose to do your own homework

mild anvil
#

im confused

slate blade
#

you basically have to click on the intercepts and that is where the functions equal eachother

#

pshhh it's lurning

mild anvil
#

yes im trying to learn

#

i dont want to fail

slate blade
#

uh, basically when you say that cos(2x) = -sqrt(3)/2

placid bone
slate blade
#

you're equating 2 functions together.

#

2 graphs are intersecting at certain points so to say

#

loona are u still alive

#

anyhow

mild anvil
#

yes im still alive

slate blade
#

so to find where they equal oneanother, you look at the intercepts of the graphs between the domain indicators

#

does mathway allow you to analyze intercepts?

mild anvil
#

im just trying to comprehend

#

no maybe i should use desmos

slate blade
#

click this

desert vortex
#

🇧 🇷 🇺 🇭

slate blade
#

I already have like 7 graphs named stuff so I needed a creative name

mild anvil
#

OMG

#

I MUST BE BLIND

#

WTF

#

I DIDNT SEE THE PURPLE LINE

slate blade
#

...

#

we all have our days

#

today apparently isn't any of ours

mild anvil
#

thank you for understanding

#

ive had a rough day today

slate blade
#

F well

#

alright you can also solve this through normal "analysis"

#

just by solving $\arccos{\frac{-\sqrt{3}}{2}}$

somber coyoteBOT
slate blade
#

and make that = 2x

#

expand the domain and badabing badaboom

#

that wasn't an ideal explanation was it lol

mild anvil
#

no im sorry im just dumb

slate blade
#

anyways do you get how to solve it graphically?

mild anvil
#

kinda

pure cape
#

easiest way is to just remember the special angles

#

and the values their trig funcs compute

#

there arent much to start with

slate blade
#

any other questions?

mild anvil
#

i do have more problems but im trying to solve this

slate blade
#

k msg if you have issues

mild anvil
#

okie

#

youve been a lot of help thank you and sorry for bothering you

#

all of you actually

upper karma
#

The point P lies on the unit circle, making an angle of measure \small \theta with the positive \small x-axis.

Use the cosine and sine functions to express the exact coordinates of P in terms of angle \small \theta.

jaunty marsh
#

Draw a right triangle and label sides x and y for point P with coords (x, y)

#

Use opp/hyp and adj/hyp for sine and cosine

#

I think

umbral snow
#

What are the definitions for sinθ and cosθ? If you know that, this question is immediate

#

AV is correct that doing the above will get the right answer, but knowing what the unit circle is is important

slate blade
#

sinθ and cos theta are special ratios between the sides of a right angle triangle

#

that's the "best" way I can think of defining it

umbral snow
#

After the unit circle is introduced, there's a different definition

slate blade
#

true but in the end, it's still the same "idea" isn't it. within the unit circle, it is still a ratio between the traingle, its jsut that one side is 1

upper karma
#

thanks

#

My teacher didn't teach us any of that

slate blade
#

what is with bad teachers lmao

umbral snow
#

It isn't, it fails for negative lengths

white cradle
#

hmm

slate blade
#

what is your proposed definition then?

umbral snow
#

Okay, I'll give the answer.
Take the terminal arm with angle θ. Where that intersects the unit circle is (cosθ, sinθ)

upper karma
slate blade
#

so just a coordinate system?

#

@upper karma they are known as "similar angles" I think. Basically, it is just variations of the angle pi/4, and you must consider the CAST thing

#

wait @umbral snow sorry to disturb but why does it not work for "negative length"

#

cuz the length's direction is just down isn't it? which is still possible

umbral snow
#

What's "down" for the side of a right triangle?

upper karma
slate blade
#

well I'm thinking of this from a physics POV but can't you arbitrarily define it?

silent plank
#

negative length...

slate blade
#

like if you went Up and Right are positive, Down and Left are negative

#

doens't that work for vectors and forces?

placid bone
#

mmm

#

so length is known as a scalar quantity

slate blade
#

sorry I'm still in High school and am still barely into university pants yet

placid bone
#

and scalar quantities, cannot be negative

#

this is still high school maths

#

if you do physics it's grade 11 physics

#

if not, it's grade 12 maths

slate blade
#

I am grade 11 lmao

umbral snow
#

"Ratio of a triangle's sides"
Works until something like cos(135)

#

Then it doesn't and you have to lean on unit circle def

placid bone
#

so basicallly, things like speed, number of things, length are known as a scalar quantity

#

cannot be negative

slate blade
#

ah ok make sense

#

I'm just dumb then

#

thanks for the new definition

placid bone
#

but stuff like velocity can be negative

slate blade
#

vector quantity right

placid bone
#

since they're known as vector quantities

#

yeah

#

the negativity can represent direction

#

so in essence, scalar can't be negative, vector can

slate blade
#

ah ok ty

white cradle
#

for example electric charge maybe

upper karma
slate blade
#

Numerous, what's the formula for period

#

$$period = \frac{2\pi}{b}$$

somber coyoteBOT
slate blade
#

use this and try to figure it out

placid bone
#

a quick google search seems to corroborate with my information too...

white cradle
#

thats only the specific scalars you define as the norm of something

placid bone
#

i mean as far as high school maths goes, you don't get negative scalars

white cradle
slate blade
#

I think that's just due to the "reference point of 0"

placid bone
#

doesn't negativity indicate direction though?

white cradle
#

not for charge

placid bone
#

so negative charge means that electricity is moving away? idk how charge works

slate blade
#

like for temperature, a scalar quantity, reference fo 0 degrees celcius

white cradle
#

yes for temperature that argument works

#

not for charge

white cradle
#

but i guess its just semantics at this point

#

since you could just shift the reference like doodaide said

slate blade
#

Yeah. to us it's more of an assumption that we've made

#

cuz Charge Positve or negative is really just an arbitrary definition we've created

#

that purely describes how the two dipoles interact

#

They don't really have any meaning beyond describing how they interact with each-ther

white cradle
#

how about this, we say dot product of two vectors results in a scalar

#

and theres certainly cases where that results in a negative value

slate blade
#

yeah I guess let's just go with that

placid bone
#

well ig my definition is flawed in that aspect i guess XD

#

so a more refined definition for scalar is any quantity without a direction?

white cradle
#

yeah thats all

slate blade
#

more like it is completely described by a single positive quantity

white cradle
#

but i guess you can always 'shift your scale' to make it positive if you want

slate blade
#

bruh this is why we need servers like this

steep temple
#

how do parabolas exist as conic sections if the cone is infinite? wouldnt the plane cutting into the cone form a hyperbola?

dusky surge
#

The plane of a parabola should be parallel to the corresponding tangent plane of the corresponding cone.
Therefore there will be not interception between the two planes.

dark sparrow
#

@steep temple hyperbolas are conic sections too

#

but if you angle the cutting plane in such a way that it's parallel to one of the generating lines of the cone, you get a parabola. and thats the only way to get a parabola.

#

any other orientation gives you either an ellipse or hyperbola depending on if the plane goes through one or both parts of your bicone

patent berry
cosmic bear
#

I'd recommend working backwards on this one. Try to find a formula for getting the area in terms of the sidelength, and then use that

placid bone
#

ah

#

herons formula

patent berry
#

Ty

placid bone
#

huh

#

wait you were talking to thecaptainyaya

#

lol don't take my suggestions seriously

#

i was messing around LMAO

steep temple
#

@dark sparrow somehow i am having a really hard time trying to form a parallel plane to this cone

dark sparrow
#

yeah cause you have to be exact

#

and also not have the plane pass through the apex, ftr

steep temple
#

ive pretty much manually bruteforced all the combinations and i dont get any parabola

#

its either a hyperbola which would exist if i imagined the cone is infinite, or an ellipse which for some reason never evolves to a parabola

dark sparrow
#

say, what even are those parameters you're controlling?

steep temple
#

from a 2d perspective, the y parameter is shifting the plane on the x axis and the z parameter is shifting the plane on the y axis

#

the angle controls the tilt of the plane

#

the simulation is available here, please do let me know of the combination which results in a parabola

#

it's not like the simulation does not allow for a parabola - the website mentions you can construct parabolas but i cant seem to manage

inland canyon
#

Line x is tangent to the circle. what is its length?

#

man imma be honest my teacher is kinda bad

#

<@&286206848099549185> could use some assistance

#

would i use the pythagorean theorem

upper karma
#

Do you have a better pic

inland canyon
#

well i mean i fucking drew it bruh

#

i could like

#

try to draw it better lmao

upper karma
#

Or... take a pic of the question as stated

inland canyon
#

bam

#

perfect circle

upper karma
#

Okay

#

Is 12 the whole line

#

Or just the chord

inland canyon
#

oh the whole line

#

prob should have done a big line

upper karma
#

Ok then yeah you can use pythag

inland canyon
#

would that be like

upper karma
#

Bc you are given the line is tangent

#

Try yourself first

inland canyon
#

12=9.6^2+x^2

#

or 12^=9.6^2+x^2

#

breh

#

@upper karma did u die homie

upper karma
#

...no?

#

What kind of question is that

inland canyon
#

like u went silent for a sec

upper karma
#

You are not my only focus rn

inland canyon
#

was a bruh moment

#

fair enough

upper karma
#

And yeah that's correct

inland canyon
#

wait which one

#

theres 2 of them

upper karma
#

12²=9.6²+x²

inland canyon
#

ight

#

i may need more help soon so like

#

is it ok if i ping u if i do

upper karma
#

The hypothenuse needs to be squared, otherwise you are not using the pythag theorem correctly

#

Yeah ping me if needed

inland canyon
#

thanks

inland canyon
#

@upper karma i know the theorem of like getting an angle if its inscribed on the outside which is like measure1 = 1/2 (x-y)
if im not wrong

#

but wouldnt i need atleast like

#

2 pieces of information

jaunty marsh
#

You can use the fact that a radius at the point of tangency is perpendicular to a tangent

inland canyon
#

u mean the fact that its like

#

90 degrees

#

oh yeah i can like

#

do 60 + 90 + 90 + x = 360

#

120

#

nice

#

im assuming u would do something with the 15

jaunty marsh
#

Power of a point: 15^2=9(x+9)

#

Very useful for circles problems

inland canyon
#

may i ask what power of a point is

jaunty marsh
#

It’s a set of theorems that have to do with the lengths of secants, tangents and chords
Check out the link above

obtuse tapir
#

These are just extensions of the BPT

jaunty marsh
#

BPT?

obtuse tapir
#

Proportionality theorem

#

Thales theorem for some

#

Not the 90 degree arc triangle one

#

This must be some olympiad thingy

jaunty marsh
#

The Triangle Proportionality Theorem states that if a line is parallel to one side of a triangle and it intersects the other two sides, then it divides those sides proportionally.
How is this related?

obtuse tapir
#

Yes

#

It connects

jaunty marsh
#

But how? thonk

obtuse tapir
#

Look at the proofs lmao

#

Rearrange AE*CE

#

And you can see the similarity

inland canyon
#

wait

#

bruh

#

9 ix just like

#

the outside part

#

of the

#

triangle

#

wait

#

so is like

#

the uhh

#

radius

#

the 15^2

obtuse tapir
#

What is this

#

Ok

#

Use pythagorean theorem

#

15^2+x^2=(x+9)^2

#

solve

jaunty marsh
#

Could you also use power of a point?
9(x+9)=15^2

inland canyon
#

but isnt that just gonna tell me like

#

what 9 =

#

not the whole side of the triangle

obtuse tapir
#

Olympiad tricks are always faster

inland canyon
#

also is 8

obtuse tapir
#

What are you saying

inland canyon
#

u said solve 15^2+x^2=(x+9)^2

#

its 8

#

x = 8

obtuse tapir
#

Cool

inland canyon
#

wait

#

so x = 8

#

thats the answer?

#

wait wait wait wait wait

#

how did we use

#

pythogrean

#

when like

green osprey
#

speaking of proofs can someone help me after

inland canyon
#

9 only = like the half outside of the circle

#

right

#

so how the fuck

#

did we use pythogorean

obtuse tapir
#

The whole triangle is a right angled triangle

jaunty marsh
#

Angle between 15 and radius is a right angle

inland canyon
#

mhm mhm

obtuse tapir
#

15 is a tangent

#

And tangents are perpendicular to the center

inland canyon
#

ok so

#

15 is tangent

#

that means 15 is perpendicular to the center?

obtuse tapir
#

The line of length 15

inland canyon
#

like the line

obtuse tapir
#

is perpendicular

#

Yes

inland canyon
#

ok

#

but

#

but h o w

#

like

#

like i get the angle

#

is 90 degrees

obtuse tapir
#

The proof for why tangents are perpendicular?

inland canyon
#

but how does that help figure out the radius

obtuse tapir
#

Algebra

inland canyon
#

ok karl lets dumb this down a bit

jaunty marsh
#

X is the radius

#

You solved for x

obtuse tapir
#

The triangle connects algebraic expressions

inland canyon
#

ok lemme reask this

#

how did u write up the pythogorean theorem if u didnt know what the whole side was (radius + 9) or (x+9)

#

how ever u wanna write it

obtuse tapir
#

I dont understand

#

What do you mean

inland canyon
#

bruh

#

so like

obtuse tapir
#

The pythagorean theorem works for right angled triangles

inland canyon
#

mhm

#

mhm

#

b u t

#

like

#

what i was thinking was like

#

(9+x)^2 = x^2 + 15^2

#

oh

#

thats

#

thats litterly how you write it out

#

man

#

im dumb

obtuse tapir
#

Nice

inland canyon
#

nice

obtuse tapir
#

speaking of proofs can someone help me after
@green osprey what is it

green osprey
#

uh nevermind

#

i figured it out

obtuse tapir
#

Good

low scaffold
jaunty marsh
#

Maybe use the fact that angle ACB is right angle

low scaffold
#

how would I know for sure?

jaunty marsh
#

It’s a theorem, an angle that sub tends a diameter is right angle

#

And then set the sides of the equilateral triangles to variables a, b, c
Then a^2+b^2=c^2 by Pythagorean theorem

low scaffold
#

that sound familiar actually

jaunty marsh
#

BC^2+AC^2=AB^2
Then express the areas of the equilateral triangles using formula $s^2*sqrt(3)/4$

#

$\frac[s^2*\sqrt(3)][4]$

#

$\frac{s^2*\sqrt(3)}{4}$

somber coyoteBOT
jaunty marsh
#

There, that’s it

low scaffold
#

s being a side

jaunty marsh
#

Yeah

low scaffold
#

Ok thanks i'll try it

low scaffold
#

Thanks I got it

jaunty marsh
#

👍

green osprey
#

can someone work through this problom with me

#

its really confusing

jaunty marsh
#

||Use vertical angles||
||Then triangle congruency through SAS||
||Then CPCTC to prove parallel lines through angles||

#

Try the hints one at a time

#

I don’t have much time to explain it more than that sorry

green osprey
#

ok

#

ty

old jasper
upper karma
#

What have you tried

#

And which one out of all

old jasper
#

i can't get any of those 3 mainly b

#

i am just stuck in all of them don't know where to go

upper karma
#

Ok our goal on a and c is to get to the form of log(something)=something

#

Are you able to try at least with a once, knowing the your log laws $\ \log(a)+\log(b)=\log(ab)\ \log(a)-\log(b)=\log(\frac{a}{b})$

somber coyoteBOT
upper karma
#

Uh

#

Are you able to try at least with a once, knowing the your log laws $\ \log(a)+\log(b)=\log(ab)\ \log(a)-\log(b)=\log(\frac{a}{b})$

somber coyoteBOT
upper karma
#

@old jasper

#

...

inland canyon
#

bruh

#

Whats the value of x

#

wouldnt all the degrees add up to 360 bruh

#

cuz then it would be like uhh 22

#

222*

#

but the angle is acute

#

or would it be like

#

180

#

it adds up to 180 doesnt it

#

😔

autumn bloom
#

Ain't it 138 because a triangle has to add up to 180, 360 would be a rectangle if I remember correctly

inland canyon
#

ye but like

#

acute angle

#

pretty sure its 42

autumn bloom
#

Wait no Im also dumb

#

I added the both up

#

Yea it's 42 not 138

low scaffold
#

Every triangle's angles add up to 180 degrees

#

yea 42

inland canyon
#

ight c00l

#

man fuck math

#

who invented math

#

yo fuck greek people all my homies hate greek people

autumn bloom
#

It's so confusing, too many numbers 😔

#

Once you know it, it can be fun tho

low scaffold
#

^

inland canyon
#

man

#

this image

#

explains my pain

#

also cannedfruit i like ur pfp homie

autumn bloom
#

Thank you 😎

inland canyon
#

welcome

low scaffold
#

Anyone able to help with this? I’ve tried to differentiate it but now I’m stuck

pure cape
#

Well you were almost there

#

You know that the derivative at that point is also the slope of the tangent line

#

so you got the slope of the linear equation y= mx + c where m is the slope

#

So now you have to find c

#

You can do that by substituting x=a into the linear equation

low scaffold
#

Ohhhh

#

Ok

#

Like this?

astral bluff
#

Hi guys can someone help me with a hw question?

pure cape
#

Uh no, you did it wrong

#

Your derivative is right but your subsitution is wrong

low scaffold
#

How should it be?

pure cape
#

right can you tell me what m might be?

low scaffold
#

Using the value of a I got:

pure cape
#

Yes which is 4e^4a right?

low scaffold
pure cape
#

Oops missed a bracket there

#

Oh yeah, this is geometry

#

Lol didnt even notice

low scaffold
#

I thought because of the tangent line it should be here

upper karma
#

It's fine ig, this comes from a geo problem

low scaffold
#

Where should it be?

#

ok

pure cape
#

I mean its quite on the calculus side, but doesnt matter

#

Yeah, so we got the slope

upper karma
#

It's fine here ig, i just didn't see that this problem was originally a geo problem

pure cape
#

So our equation now is 4e^(4a)x + c = y

low scaffold
#

ok

pure cape
#

You also know that the line crosses thru (a;e^(4a))