#geometry-and-trigonometry

1 messages · Page 295 of 1

weak shoal
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yea

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Yea sure

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pi = 180

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so each angle has measure 60 degrees

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or pi/3 radians

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? have you not covered this in class?

ancient vine
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2a

dark sparrow
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have you made a diagram?

upper karma
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F

finite vigil
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Does anyone have time to help me with some Geometry IXL work? Similarity Theorem? If so please @ me thank you in advance! 😄
If I don't get the ping I won't know you responded haha

upper karma
finite vigil
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Should I send the question?

upper karma
finite vigil
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Also I love your legoshi picture

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Beastars is bomb! I wish there was another season

upper karma
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there will be a second season

finite vigil
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Oh crap wrong ss

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also yayyy

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this is the one haha my bad

glacial haven
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just use pythagorean

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theorem

upper karma
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it's been a long time since ive worked with similar triangles, so lemme try to recall how things should work out here

finite vigil
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The pythagorean theorem doesnt work for this one @glacial haven

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also okay np TTerra

glacial haven
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why doesnt it?

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oh

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i didnt read it carefully

upper karma
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well, first you want to figure out some similar triangles in the diagram here, and then look at the ratios of corresponding sides

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those ratios will be equal iirc, so then you use the given information to find KM

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just a matter of picking the right correct triangles and ratios

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which is, for some reason, escaping me

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alright, here is my suggestion: see if the triangle i shaded in red is similar to the entire triangle (i am choosing to use this triangle in the diagram because i know two sides of it, and so it's more likely to tell me more information via similarity)

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and then because the triangle in red shares a side with the entire triangle, you can use the fact that corresponding sides of similar triangles have equal length ratios to finish the problem

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(i actually haven't done this in about 4 years so sorry it took so long to get something out)

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@finite vigil

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(im assuming the similarity theorem has something to do with justifying that the triangles are indeed similar)

glacial haven
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wait you do use pythagorean

upper karma
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maybe you can use pythagorean and some trigonometry

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but it's asking (implicitly) for similarity to be used

meager pendant
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I need some help with this question.

upper karma
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Draw DA

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<COA=2*<CDA

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<CDA=<CDE-...

finite vigil
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ty terra for the help my teach explained we can solve it thru a table

arctic vortex
upper karma
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@meager pendant still here?

meager pendant
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yeah

upper karma
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Solved it?

meager pendant
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not yet

upper karma
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Have you taken a look at my advice?

meager pendant
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not yet

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I’ll do it tomorrow morning tho

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cause it’s almost 1 am

upper karma
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Ok

meager pendant
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thanks for your concern tho , I’ll report back to you

upper karma
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Ok

livid sequoia
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I got the answer for this but I want to know how to actually do it step by step can someone explain?

dark sparrow
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how did you get the answer?

livid sequoia
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My teacher told me last second and she left, I wanted her to explain how but the class ended

dark sparrow
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okay...

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big picture, there are two steps here

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  • calculate the area
  • calculate the total cost
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the area can be calculated in a bunch of ways, but they'll all involve rectangles combined in one way or another

livid sequoia
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A = L x W, so the L would be 3 and the W would be 3.6?

dark sparrow
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this is just one of the rectangles in one of the possible area calculation methods

livid sequoia
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oh

upper karma
livid sequoia
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I use pi?

dark sparrow
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...no

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there are no circles here

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if you subtract off the area of that little white rectangle in the corner, you will get the area of the bedroom.

livid sequoia
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3.6 minus the 1.2?

dark sparrow
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what does that give you?

livid sequoia
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2.4

dark sparrow
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no

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i didn't ask you to calculate it

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i asked you what the answer would represent for this problem

livid sequoia
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that would give you a rectangle

dark sparrow
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no, it'd give you a number.

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what does the number represent?

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what does this 2.4 figure mean for the problem?

livid sequoia
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the width

dark sparrow
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the width of the white rectangle, great.

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so now what's the area of the white rectangle?

livid sequoia
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2.4 times 0.6= 1.44

dark sparrow
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great

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so do you understand how to continue the problem from here?

livid sequoia
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you add the 3.6 with 1.44?

dark sparrow
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why would you add a length to an area

livid sequoia
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10.8 + 1.44?

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times*

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waiy

dark sparrow
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10.8 m^2 is the area of the red rectangle
1.44 m^2 is the area of the white rectangle

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what would their sum represent?

livid sequoia
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the entire rectangle

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or bedroom

dark sparrow
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don't you think the white rectangle, instead of being counted TWICE as you did, shouldn't be counted AT ALL?

livid sequoia
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I guess not since its not part of the bedroom

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can we cut it, do the L x W with 3.6 and 3 and the area for the small piece 0.6 times 1.2?

dark sparrow
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3.6 * 3 will give you the red rectangle

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if you're asking whether or not you can cut it up like this: you can

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but the blue rectangle will not be 3.6 by 3

livid sequoia
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ohh

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I subtract 3 minus the 0.6 then use L x W

dark sparrow
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if you want to phrase it that way, sure...

livid sequoia
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2.4 times 3.6 = 8.64

arctic vortex
livid sequoia
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then I can do 0.6 times 1.2= 0.72+8.64= 9.36

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then times that by $9.50

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OH

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Thank you!

arctic vortex
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good luck in ur test corosu

livid sequoia
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I'll get a high score thanks to Ann

arctic vortex
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yeah ann is a genius at geometry

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@dark sparrow sorry for the ping but can u check my asnwer??

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for tihs one is the answer 1788.30

dark sparrow
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did you write this problem yourself

arctic vortex
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yesss

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and its actually a typo

dark sparrow
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you have conflicting info between the problem statement and the diagram

arctic vortex
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10000 is actually 1000 and 5000 is actually 500

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oh

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what do i do need to change?

dark sparrow
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well ok you've cleared up the altitudes

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what's the angle of elevation supposed to be

arctic vortex
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from the bird to the airplane

dark sparrow
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i got that much

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but is it supposed to be 34 (as per the diagram) or 64 (as per the text)

arctic vortex
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or is 34

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i changed that as wlel

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its 34

dark sparrow
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ok

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then the answer becomes 894.1 feet

arctic vortex
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what

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how

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is it the distance from the bird to the plane

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i used sin34 = 1000/x if that is correct

dark sparrow
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no it's not

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the duck isn't at ground level

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it's 500 feet above the ground

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so the vertical distance between the duck and the plane is 1000 - 500 = 500

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(feet)

arctic vortex
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ohh

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what would happen if i make the bird at ground level

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and the plane 500 feet

dark sparrow
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the calculation would happen to be exactly the same

arctic vortex
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oh

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im confused on how u got 894.1

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how did u get that

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@dark sparrow

dark sparrow
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500/sin(34°).

arctic vortex
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wait

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instead of 1000 u did 500?

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@dark sparrow ?

dark sparrow
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the duck isn't at ground level
it's 500 feet above the ground
so the vertical distance between the duck and the plane is 1000 - 500 = 500

arctic vortex
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OHHHH

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wow ur iq mustbe very high

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i didnt acknowdledge that

dark sparrow
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IQ is meaningless

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this is stuff from like 5 years ago to me

arctic vortex
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oh

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well i got 894.1 as well

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once i did 500 = x(sin34)

finite vigil
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I need helps

upper karma
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@finite vigil is it a test?

finite vigil
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it's IXL

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It's a homework

upper karma
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Okok

finite vigil
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I'm on this one rn

upper karma
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Actually its a special right triangle

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So do you know the relationship between the sides? @finite vigil

finite vigil
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no

upper karma
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@finite vigil srry had to eat, still need help?

finite vigil
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yes

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pls

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@upper karma

upper karma
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Okay so

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Hold up

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Click on it

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That's a truth for every 30 60 90 triangle with the angles in those positions

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@finite vigil

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x can be whatever and the truth will hold as long as it has the conditions i said above

finite vigil
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I clicked on it

finite vigil
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ty

upper karma
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Here is the proof behind it

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Np

upper karma
gritty flicker
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Could someone help

silent plank
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where are you stuck?

gritty flicker
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entire question

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actually

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nevermind

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i got it

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this one

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is the one i dont get

silent plank
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have you tried drawibg a diagram?

gritty flicker
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i did this

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but idk where 1.6 comes in

silent plank
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his eyes are at the bottom left corner

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right?

upper karma
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but idk where 1.6 comes in
@gritty flicker you know that the eyes are not on the ground right?

silent plank
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so indicate that that position is 1.6m above the ground

gritty flicker
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oh

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should i do

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tan 51 = 26/x

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then subtract by 1.6

glacial haven
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no

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redraw the diagram

quick gyro
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You might want to include the tree, ground, and thomas' eyes

silent plank
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(use ruler/line tool)

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also tan isn't being applied properly

upper karma
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Think about angles

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👏 👏

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@upper karma note that the triangle XYZ is isosceles...

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Actually equilateral...

arctic vortex
silent plank
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can't you fix your diagram or text for the details to match?

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diagram labels could be clearer, that 1000 could be misinterpreted as the distance of that edge instead of plane altitude

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also 10000ft actually seems like a more reasonable flight height. i'd be concerned if a plane was flying horizontally (not landing/taking off) at 1000ft

upper karma
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Actually equilateral...
@upper karma holy fuck why did i not realised lol

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@upper karma hello?

upper karma
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👻 👻

meager pendant
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i don't know how to find <ADE

dark sparrow
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look at angles ADE and ABE

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notice anything?

upper karma
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yes its awesome

meager pendant
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they equal

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thank you

vapid vector
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How do we know that they are equal?

silent plank
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inscribed angle theorems

vapid vector
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Oh ok

meager pendant
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this is the proof i used

dark sparrow
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this is not a proof

meager pendant
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oh

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ok

dark sparrow
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it's the statement of a theorem

arctic vortex
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can anyone check my homework answers for like 10 questions?

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and i might need help with some questions

dark sparrow
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if possible, could you post the questions all at once and your list of answers, so that we don't have to go through them one by one?

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i for one find that extremely annoying

arctic vortex
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oh ok

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i will do that

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1 second

upper karma
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👻

upper karma
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I didn't know 1 second lasted 1h

arctic vortex
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no wait 1 second

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@dark sparrow ann i am back can u still help me sorry

dark sparrow
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if possible, could you post the questions all at once and your list of answers, so that we don't have to go through them one by one?

arctic vortex
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oh ok

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5 minutes pls

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i think its the pythagerona theroen

dark sparrow
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so much for not going through them one by one huh

arctic vortex
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sorry

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ok i will do that

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i like to do things where after i finish 1 i go to the next

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@dark sparrow wait so is it the pythageoran theorem

dark sparrow
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all at once, please.

arctic vortex
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oh

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ok wait

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there are 24 questions in total

dark sparrow
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all at once.

dark sparrow
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okay, i see the questions. can i have your answers for them all?

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no, i am not going to verify them one by one.

arctic vortex
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ohhhh

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ok

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can u help me with this

dark sparrow
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what don't you understand about this?

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do you know what it means to fold something in half?

arctic vortex
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i dont know how to get x

dark sparrow
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that neither answers my question nor makes it clearer to me where your confusion lies.

arctic vortex
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i dont understand how to get x

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ohhhh

stray pelican
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wait i made a mistake

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ignore that

arctic vortex
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oh

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ok

stray pelican
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ill reupload

arctic vortex
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whats a side length

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is it the hypotenuse

stray pelican
arctic vortex
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oh

stray pelican
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make sense?

arctic vortex
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isnt it suppposed to be tan

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tangent

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because opposite and adjacent

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and yeah it makes sense now

stray pelican
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I'm just using law of sines

arctic vortex
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oh ok

stray pelican
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you get it now?

arctic vortex
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yesss

stray pelican
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good

arctic vortex
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the other one makes sense now

dark sparrow
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to be honest i'm not terribly inclined to help at this point

arctic vortex
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oh

stray pelican
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im not gonna tell you the answer i want you to figure it out but ill give u a hint

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it looks like you should use the pythagorean theorem

arctic vortex
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oh ok

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i will use that

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by the way how do u get honorable rank

arctic vortex
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guess what guys

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i got a 23/24 on my homework

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now i need to study for the test

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yesss im quite a genius

royal edge
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AED is a straight line. I am completely stumped on this question

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It’s not a parallelo gram

upper karma
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@royal edge consider sine law

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On the triangle CEB

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Then cosine law

upper karma
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👻

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??

weak shoal
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@upper karma What is the issue you're having?

upper karma
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i dont rly understand

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it at all

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...

idle bobcat
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Hello, so I know that <QPR + RPS = 180, and thus u can solve for x, but can't you do the same thing by doing 180-<QPR = <RPS?

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because if you subtract one angle from 180, cant you find the other angle

stone adder
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Yeah, you can do that

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since 180 degree - <QPR = <RPS is derived from <QPR + <RPS = 180 degree

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It's the same thing, since in the end you're asked to find the value of x, which <QPR and <RPS has x on them

idle bobcat
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ok just making sure, because when i did it this way i keep getting the wrong answer

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so im doing 180-2x+122 = 2x+22

stone adder
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Can you show your work?

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Oh

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$$180-(2x+122)=180-2x-122 \neq 180-2x+122$$

somber coyoteBOT
stone adder
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Recall the distributive properties

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when you work with parentheses

idle bobcat
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ahhhhh

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yeah that makes sense now

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tyvm!!

stone adder
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You're welcome!

silent plank
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what have you thought about?

upper karma
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Everything

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The meaning of life

tidal river
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Can someone help me with the geometry question

royal edge
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Quantum try drawing it out first

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Let’s start with that, and once you do that, tell me

upper karma
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F

royal edge
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Xi can you send me that profile picture?

upper karma
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Hmmmm

royal edge
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Pretty please?

upper karma
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@tidal river #6241

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@royal edge

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Help this guy

upper karma
stone adder
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What's foci?

upper karma
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idk but it's asking for it

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focus

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oh

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how do you get it

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yes

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what

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I believe there's a formula

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yep

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Google it

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k ty

sleek thistle
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how do i find y in this?

upper karma
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@sleek thistle (4y+4) and 60 are supplementary angles

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Do you know what that means?

sleek thistle
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ohh you’re right omg

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180

upper karma
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Yeah they add up to 180°

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Set up an eqn and solve for y

sleek thistle
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okay thanks lmao

upper karma
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Np

finite vigil
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Could anyone help me with a trig IXL? I need to get up to an 80 if so please @ me ty in advance

deep stump
upper karma
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seems pretty hard

dark sparrow
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@deep stump do you still need help with these

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and if so, which ones

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ok, now that you've (presumably on accident) DM'd me saying you do need help on these

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which ones do you need help on

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@deep stump are you gonna respond here or are you gonna insist on DMing me even after i've made it clear i would prefer you didn't?

deep stump
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@dark sparrow It's just clear to me now, thanks

dark sparrow
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okay so are you gonna answer my question

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which of these problems do you need help with

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so that we can go through them in order

deep stump
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@dark sparrow They clear to me now, when I need help with other ones, I ll ask again, thanks

dark sparrow
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ok

sleek thistle
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anybody know of a rule or just how to get this length?

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don’t even know how to start

dark sparrow
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consider that ABCD is a rectangle, as the problem literally tells you

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what do you know about the diagonals of a rectangle

sleek thistle
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oh

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well the diagonals are congruent

dark sparrow
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yup

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and what can you say about BC, the other diagonal of the rectangle?

sleek thistle
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that it’s equal

deep stump
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@dark sparrow available now?

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I have this problem to find the eccentricity of an ellipse if the sides of the square inscribed in it pass through the foci of the ellipse. Can you help?

sleek thistle
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omg

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it’s 5 i’m a pop tart

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damn

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well i overthought the shit out of that for no reason

dark sparrow
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@deep stump have you made a diagram yet

deep stump
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I am doing game development and I had to solve this problem

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@dark sparrow How would you solve that?

dark sparrow
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well my first step would be to make a diagram

deep stump
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can you help more?

dark sparrow
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notice that this diagram is symmetric about both axes of the ellipse so we have that F1 and F2 are the midpoints of AD and BC

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taking $AF_1 = 1$ for convenience, we have that $$2a = F_1P + F_2P = F_1B + F_2B = \sqrt{5} + 1$$ and $c = F_1O = 1$

somber coyoteBOT
elder shuttle
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does anyone know what is arcsin(1 - sin^2x)?

dark sparrow
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i don't think this can be simplified any further than arcsin(cos^2(x)) @elder shuttle

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is there a problem you're doing where you found this expression?

misty plume
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Anyone has a intuitive method to part a? I ended considering the area of an individual triangle then multiplying it by n sides for A, but would be cool to know if there are faster methods...

dark sparrow
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nah that's p much the fastest

royal edge
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nvm

arctic vortex
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Can anyone help me with this please

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Your explanation is not correct, you state that the given pair of angles that add up to 180 are supplementary In your correction, please state the name of this supplementary angle pair, as formed by parallel lines cut by a transversal?

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this is what the teacher said

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oh

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never mind

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i just need to name the angle pair

royal edge
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Makes sense

arctic vortex
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yes

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@royal edge what kind of angle pair is this??

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i think its congruent angles or consecutive interior angles

royal edge
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I got it, it was SAS

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They were corresponding angles Bcs they were parallel lines cut by a transversal

elder shuttle
dapper solstice
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hi i need some help with trig pls, i dont get when to use or how to see which one to use between cos sin and tan

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why do they use tan here and not anything else, also how do they get 23degrees from 0.429??

dark sparrow
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tan(α) = 0.429

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α = arctan(0.429) = atan(0.429) = tan^-1(0.429)

dapper solstice
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emm

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how do i write this in my calc? tan(0.429)^-1?

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tan^-1(0.429) this gives me error

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also is it ^-1 for all sin cos tan to find its degree

silent plank
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depending on the calculator, probably a variation of
shift + tan
or
function key + tan

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or some trig submenu

dapper solstice
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hm

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i do have mode button but that only changes from radian to degree and vice vers

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assume thats the wrong 1

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ooooooooooooo i found it n v m

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it was just the "2nd" button lul

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ty brother

upper karma
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books answer

silk crown
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so, what was your approach

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you said you used the cosine rule?

upper karma
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cosine rule

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yes

silk crown
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ok, send me your working/reasoning

upper karma
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I know my handwriting isnt the best

silk crown
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let me see

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what is the cosine rule @upper karma

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you did not write an equation lol, if you did it would have been clearer

upper karma
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c^2=a^2+b^2-2abcosC

silk crown
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yes

upper karma
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yea i was kinda rushing

silk crown
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then write the equation this time

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c^2 = ....

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and then at the end take sqrt on both sides

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your expression is correct, but the square root of that is the answer

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i checked with a calc and it is the right answer

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¯_(ツ)_/¯

upper karma
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I'm gonna check the book's answer

silk crown
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5.6cm lol

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you get 5.59... something

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this is why you dont rush

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write your equations properly

upper karma
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yea the books answer is the same as written

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I got 5.598 for my solution

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Book's answer is 5.64861 which i just checked

silent plank
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the books crap

silk crown
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oh lmao i only saw their final answer

upper karma
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so there answer is wrong?

silent plank
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actually 1 sec

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i think the diagram is actually inconsistent

silk crown
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D and A

silent plank
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theoretically, both the sine and cosine laws can be applied, but due to rounding issues, the values obtained are off

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cosine law only focuses on triangle ADC. calculations using that don't rely on external info which is what you applied and what i'd recommend

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although you should make your square root clearer

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and don't split equations on two lines

upper karma
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my bad again i was rushing through this

silent plank
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(there's rushing and there's being oblivious to math rules/ettiquete)

upper karma
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true

silent plank
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based on the values within triangle ADC, angle ACD actually works out to be around 99°

silk crown
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im pretty sure the book's working is wrong though

silent plank
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nah, its just that the values are inconsistent

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if they were actually consistent, applying the sine law like that would get the same result

upper karma
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uhh this is already on the interenet

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apparenlty its a common problem

silent plank
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yeh. over specification is an issue

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leads to multiple different answers from "correct" methods

upper karma
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so which is the correct answer?

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I assume no correct answer or both are

silent plank
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both methods are acceptable

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but technically there are no correct answers due to inconsistencies

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but i mean if you're rounding to 1dp

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you'd get 5.6 for both which is just a coincidence

arctic vortex
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what is this

wooden current
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bruh

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@arctic vortex What's giving you trouble

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Unless you have solved it already

arctic vortex
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o i solveed it

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my fault

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i forgot that f was outside of the parallelogram

wooden current
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It's ok. Sorry for the ping 😅

arctic vortex
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its ok

upper karma
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just wondering is there a name for when imput to trig funcsions are the same?

upper karma
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like are you looking for a circle that touches everypoint?

nova prawn
#

like are you looking for a circle that touches everypoint?
@upper karma no, i have found what i was looking for, thanks again 🙂

upper karma
#

Yes

nova prawn
#

how?

upper karma
#

@nova prawn yeah hold up

#

$m\cdot m_{\perp} =-1$

somber coyoteBOT
upper karma
#

Id just write it but its kinda long

#

Lol

#

That's a long proof that's fine

#

I mean if you wanna write it and i remove the video go ahead

#

Btw there's no proof in the video

#

Shoot

nova prawn
#

yeah only formula

upper karma
#

Now lol

#

I mean im not fan of formulas

#

Here's the geometric proof

nova prawn
#

thanks a lot

upper karma
#

There are better ways of approaching it

#

But whatever

nova prawn
#

like what?

#

@upper karma

upper karma
#

Finding perpendicular to the line that goes through the point and the the intersection between line and perpendicular

#

Then distance between two points

#

Like for example to draw an auxiliary plane

#

The connection was bad there and it got sent half an hour later but yeah

#

Oh i was referring to the auxiliary plane

#

@nova prawn

#

May i post another video of it lol

nova prawn
#

ofc

upper karma
#

F there are no english good videos

#

In my lative there are some

#

(Spanish)

#

Shieet

#

Post anyway

#

Ig you can put subtitles

#

What if we speak spanish

upper karma
#

Lol

#

@nova prawn does it cover auxiliary plane method

#

^ that's what I was trying to say

#

Sniped headshot

nova prawn
#

what is that

upper karma
#

The method i was all the time referring to is a better method than the formula one

nova prawn
#

I will check that as well

#

thanks but i am actualy working with circle

upper karma
#

Put eng subtitles on as well

#

Kk

nova prawn
#

like I have the center and the equation of tangent line

#

how to find radius, hope those will work

upper karma
#

Damn

#

Yeah they will definitely

#

What lol @upper karma

#

Nothing

#

Great

#

Nice

rich mist
#

Can someone help me with a trig question ?

keen aspen
#

Uhh what are you having issues with

rich mist
#

i sent my question

keen aspen
#

Yes what part of the problem do you not understand

rich mist
#

I just need the answer

keen aspen
#

Bruh

rich mist
#

can you help me its time

#

timed

keen aspen
#

I can walk you through it

rich mist
#

okay please

keen aspen
#

So just solve the equation

#

tantheta+1=0

#

so tantheta=-1

#

Now think of a theta that when you take the tan of it, it is -1

#

Notice here that tan is negative, so theta is in the 2nd and 4th quadrant

#

What theta comes to mind

rich mist
#

what do you mean what theta

keen aspen
#

What value of theta comes to mind such that tan of it is -1

rich mist
#

idk what is it?

#

bro its timed

remote heart
#

Theta is $\theta$

somber coyoteBOT
silent plank
#

timed...

remote heart
#

is this a test @rich mist?

keen aspen
#

Lol

rich mist
#

are there 3 answers

#

I got theta = (3/4)pi

#

and (7/4)pi

keen aspen
#

Good

rich mist
#

are those the only two answers?

keen aspen
#

In that interval

rich mist
#

Hello

#

my answer is x=3/1+4logbase15(3)

#

^17 not 15

#

how would I write that with these resources

keen aspen
#

You need it in log base e or 10

urban egret
#

@rich mist PJS said it best you need to take the natural log of both sides. For some reason you don’t have natural logarithm in your final answer.

#

Review your natural logarithmic properties

signal hornet
#

how do I solve this 0= x + 2sin(x) domain [0, 2pi]

#

no idea how to get x on its own

#

I know 0, and 2 pi from just looking at the unit cricle

umbral snow
#

There's no way haha. That one isn't something doable by algebra

keen aspen
#

Yeah

umbral snow
#

,w graph x + 2sin(x)

signal hornet
#

what about with calc 1 knowledge?

umbral snow
#

In fact it looks like 0 is the only solution

signal hornet
#

my guess is to find where f' = 2

#

but that is probably just as hard

#

if not worse

umbral snow
#

Honestly yes, the derivative could help. It's pretty easy to see where the mins/maxes are because the derivative is just
1 + 2cos(x)

signal hornet
#

I want to to know x-intercept

umbral snow
#

Plug the mins/maxes into x + 2sin(x), that's enough to show that the only solution is 0

nova prawn
#

I am looking for circle's equation which has:
center on the line y = 3x and tangent to the line x = 2y at the point (2,1)

dark sparrow
#

what have you tried so far

nova prawn
#

Perpendicular line I was looking for

#

but from point, if i get perpendicular line, it will be perpendicular to line that is on center. I need perpendicular from center -> tangent not tangent -> center i think

#

I checked internet, could not find anything.

dark sparrow
#

if you construct the perpendicular to x = 2y at the point (2,1) then you get another line on which the center must lie

nova prawn
#

but it also should be perpendicular in the tangent point?

dusky surge
#

perpendicular to x = 2y at the point (2,1)

nova prawn
#

did not get it

silent plank
#

you aren't interested in any lines perpendicular to the line the center lies on

nova prawn
#

yeah, i need line that is perpendicular to tangent right?

silent plank
#

yes

nova prawn
#

then on that line some point intersects from center line

#

that must be my center

silent plank
#

yes

nova prawn
#

how to calculate this?

silent plank
#

do you know the property of perpendicular lines?

nova prawn
#

yeah, sloped are reversed.

silent plank
#

that's vague

nova prawn
#

like if one them is x, isn't the other 1/x

silent plank
#

no

#

(for non-horizontal and vertical lines) the slopes of 2 perpendicular lines are negative reciprocals of each other (or their product is -1)

#

$m_1m_2 = - 1$ or $m_1 = -\frac{1}{m_2}$

somber coyoteBOT
nova prawn
#

ok

#

but i need 2 things

dark sparrow
#

there seems to be a language barrier here

nova prawn
#

my english.

#

is it that much bad?

silent plank
#

you grammar is bad. can you at least clearly understand what we are saying?

nova prawn
#

i can understand you guys, books, videos don't worry 🙂

silent plank
#

ok

nova prawn
#

I just type fast. That's why i guess

dark sparrow
#

then type slower.

#

and read every single message you write at least 2 or 3 times

nova prawn
#

You are right, i must have thought you before i had clicked enter. Sorry.

silent plank
#

currently you are looking for equation of the line perpendicular to your tangent x=2y at (2,1) right?

nova prawn
#

yes

silent plank
#

what is the slope of x=2y

nova prawn
#

The slope of the equation x=2y is 1/2

silent plank
#

what would be the slope of a line that is perpendicular to that?

nova prawn
#

-2 as you said m1*m2 = -1

silent plank
#

yes

#

and can you determine the equation of a line with:
slope: -2 passing through the point (2,1)?

nova prawn
#

1 = -2 * 2 + b, then b = 5

#

y = -2x + 5

dark sparrow
#

congratulations

nova prawn
#

then I will solve it with center line.

dark sparrow
#

now you have two lines, y = 3x (the original) and y = -2x+5 (the one you just found)

#

and you know the center lies on both of them

nova prawn
#

Yeah, intersection point which is solution set of these 2 equations.

#

Thanks a lot, it has been like 3 years I didn't spend time with geometry, just started back. Also, sorry for mistakes while typing.

arctic vortex
#

can anyone help me

#

with geometry

upper karma
#

@silent plank @silk crown @silk crown I have found the issue... the triangle is impossible

#

I appreciate your help!

upper karma
#

@arctic vortex JustAsk

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
#

Now i am not

#

But thanks for trying !!

#

And asorry

frail rock
#

I need help with this problem. I tried setting up the cosine and sine for angle B and I ended up getting stuck.

#

I managed to get up to this point. I have a feeling that I forgot something here.

plucky marlin
#

where exactly are u stuck

frail rock
#

I have a feeling I've forgotten how to divide an integer by a radical.

#

I tried looking it up but I got something really weird when I tried to solve it

#

hold on let me look for my other work

plucky marlin
#

both ur equations for sin and cos are correct

frail rock
#

Ah, I see.

plucky marlin
#

but the thing is, the options rationalized the denominator

#

so you should do the same and see which one matches up with the options

frail rock
#

To rationalize the denominator, I just multiply it by the square root of 5 right?

plucky marlin
#

yea

#

multiply top and bottom by sqrt 5

#

cuz u dont wanna change the value

frail rock
#

Ah ok

plucky marlin
#

yeah

#

ofc

#

and cancelling out the 3's should be the first thing you do

#

just to reduce the calculations

frail rock
#

Ah I see. I thought for a moment you could only reduce it f they had the same radical

plucky marlin
#

yup perfect

frail rock
#

I think I see now how they got those answer choices. I didn't understand it at first, I guess I just forgot how to divide radicals with integers

#

So that would eliminate A and C as an answer choice because that's not even the right equation

#

Then it's either B or D

#

Wait

#

Yeah

#

wait no that would also eliminate D

#

Ah so it would have been B

#

I get it now

#

Thank you for helping me :D

plucky marlin
#

np

frail rock
brisk holly
ionic bluff
#

@brisk holly what does that notation mean

#

the R

weary drift
#

R_AB is a reflection wrt AB

austere dragon
#

this is a no brainer but are kites parallelograms but not always?

dark sparrow
#

no, there exist kites that aren't parallelograms

austere dragon
#

but some kites are parallelograms though, is it still classified as not parallelograms?

silent plank
#

kites that are parallelograms are parallelograms

#

kites that are not parallelograms are not parallelograms

dark sparrow
silent plank
#

a kite that is also a parallelogram is a rhombus

upper karma
#

Is it?

silent plank
#

the phrasing of:

are kites parallelograms but not always
has bad implications

upper karma
#

Isn't it only squares that are kits and oarlagrams?

silent plank
#

squares are rhombuses

upper karma
#

just wondering is there one triangle you can make on a sphere with three points or are there infinitely many

sly belfry
#

hello everyone! quick question.

#

can we interchange the ellipse parametrisation? instead of (cos(t), sin(t)), to have(sin(t), cos(t))?

dark sparrow
#

sure? you'll just have the curve get traced out in the other direction

#

(sin(t), cos(t)) specifically will trace the circle of radius 1 centered at the origin clockwise from (0,1)

sly belfry
#

hmm

#

I'm not very good at parametrisation, but this seems a little awkward

#

but yes -- it does make sense

#

thank you so much.

arctic vortex
#

can someone help

upper karma
#

What makes a parallelogram a rhombus?

#

For example perpendicular diagonals

#

So you can use a famous theorem....

plucky marlin
#

a homeomorphism

upper karma
#

@arctic vortex

plucky marlin
#

enuf shitposting

#

i watch movies now

arctic vortex
#

diagonals bisect each other @upper karma

upper karma
#

For example perpendicular diagonals

#

This is more useful

#

Any ideas?

#

Consider triangle MSP

arctic vortex
#

wait ohhhhh

#

the pyhagoren thoerem

upper karma
#

Yes

arctic vortex
#

because right angles

#

wow u are genius

upper karma
#

Yes

#

If pythagorean theorem were verified, then the parallelogram would be rhombus

arctic vortex
#

also this one

#

i forgot how to do this

#

i knew how before

#

i forgot

upper karma
#

What's the value of the angles of a square?

arctic vortex
#

90

#

45 45 90 triangle

#

but i dont know how to get x

upper karma
#

You said it

#

The angle must be 45

#

So 45=6x-9

arctic vortex
#

ohhhhhhh

#

ok

#

i do not know at all how to get this

acoustic bone
#

PM=13

arctic vortex
#

its only lm

upper karma
#

First of all

#

MG is parallel to AL

#

so?

#

What's the value of <MLA

arctic vortex
#

is it 82

upper karma
#

Nope

#

MG and AL are parallel

arctic vortex
#

but its right

upper karma
#

What is right?

#

Im talking about <MLA not <MAL

#

They are alternate angles...

#

So they are equal

#

But AM=AL, triangle MAL is isosceles so <AML=<MLA

#

Your turn now

#

@arctic vortex

arctic vortex
#

im back

#

its 82 because 49+49=98

#

and 180-98 = 82

upper karma
#

Yes

livid sequoia
upper karma
#

SAS

livid sequoia
#

ok I got 30 its AAS

upper karma
#

30 and 31 are yes

livid sequoia
#

both are AAS and congruent

upper karma
#

Yes

mortal mesa
#

Hi,
Having troubles solving the following equation:

$(1+\cos(4x))\sin(2x)=\cos^2 (x)$

somber coyoteBOT
upper karma
#

@mortal mesa you have to prove it or solve it

mortal mesa
#

@upper karma solve it

upper karma
#

Ok hold up this is an ass-long problem @mortal mesa

mortal mesa
#

@upper karma tell me about it 😩

upper karma
#

Just expand cos(4x)

#

Hahahah

#

@upper karma have you finished solving it?

#

I have not even tried

#

Kinda stuck lol

#

My black ink is gone and i can't see shit

#

Hahah

#

What if you use complex numbers

#

Should be juicy

#

I won't try THAT hahah

#

Why noy

#

Not

#

2 lines of solution

#

I don't think he wants that method

somber coyoteBOT
upper karma
mortal mesa
#

It's for my students. I got stuck trying to solve in class lol

#

Unfortunately, complex solution won't help

upper karma
#

Damn

#

Wait I have an idea

#

Express cos^2 in terms of cos(2x)

#

Then t=2x

#

$$(1+\cos(4x))\sin(2x)=\cos^2 (x)$$ $$(1+\cos(4x))\sin(2x)=\frac{\cos(2x)+1}{2} $$ $$
(1+\cos(2t))\sin(t)=\frac{\cos(t)+1}{2}$$

somber coyoteBOT
upper karma
#

Is that allowed

#

That's how i started

somber coyoteBOT
upper karma
#

@mortal mesa you can guess what to do now

mortal mesa
#

@upper karma @upper karma
Nice, tnx.. Sorry, but I'm not sure how to go from here. I still have that 1/2 on RHS.

somber coyoteBOT
upper karma
#

I guess

#

then cos(t) = helicopter

stone adder
#

Is $1-sin^2(2x)=cos^2(2x)$?

somber coyoteBOT
upper karma
#

Yeah

#

Yes

stone adder
#

Okok

upper karma
#

Use \cos and \sin to make it look better xD

stone adder
#

Oh yea lol

#

I always forgot about that

upper karma
#

$2u^2\sqrt{1-u^2}=u/2+1/2$

somber coyoteBOT
upper karma
#

$\sqrt{1-u^2}=\frac{u+1}{2u^2}$

somber coyoteBOT
upper karma
#

$1-u^2=\frac{u^2+2u+1}{4u^4}$

somber coyoteBOT
upper karma
#

Nice u^6

stone adder
#

Oh god u^6\

upper karma
#

:(

#

$4u^4-u^6=u^2+2u+1$

somber coyoteBOT
stone adder
#

Btw I tried the question and got, $$2 \sin{2x}[1-\sin^2{2x}]=\cos^2x$$

upper karma
#

Damn son

somber coyoteBOT
upper karma
#

@mortal mesa

#

$u^6-4u^2+u^2+2u+1=0$

somber coyoteBOT
upper karma
#

,w u^6-4u^2+u^2+2u+1=0

somber coyoteBOT
stone adder
#

Oof

upper karma
#

Wait

#

It's wrong

#

Yeah lol

#

,w u^6-4u^4+u^2+2u+1=0

somber coyoteBOT
upper karma
#

Still fuck

#

Try putting the trig

#

Back?

#

Like what you said u is

#

$u^6-4u^4+u^2+2u+1=0$

somber coyoteBOT
upper karma
#

Like u=cos(t)?

#

This is shit

#

Like what did you sub for u

#

Ikr whatever

#

Like u=cos(t)?
Doesn't look good

#

Doesn't look good
@upper karma i mean, what did you u-sub on

#

Yes but

#

No bueno

#

Rip

solar shale
#

I got 51 is that right?

dusky surge
#

I'm quite sure it is not 51

solar shale
#

How would I go with solving it

silent plank
#

what were you doing to get 51?

solar shale
#

I got two different types of problems mixed with this question

drifting drift
#

12/9=x/8.5

solar shale
#

So cross multiply 12 and 8.5 then divide by 9?

silent plank
#

not a fan of how the term cross multiplication is being thrown in here

#

firstly do you understand how to get that initial equation?

solar shale
#

Sort of

silent plank
#

properties of similar figures

#

as for isolating x, simply multiply both sides of the equation by 8.5

sleek thistle
#

am i supposed to make it equal to 9 since it’s equilateral?

dark sparrow
#

make what equal to 9?

sleek thistle
#

3/2x+30

dark sparrow
#

does an equilateral triangle have angles equal to 9 degrees?

sleek thistle
#

equal to 180 right

dark sparrow
#

what's equal to 180

sleek thistle
#

the entire triangle

dark sparrow
#

the SUM of the ANGLES in the triangle is 180°

#

but what's the measure of ONE angle in an EQUILATERAL triangle?

sleek thistle
#

60

#

i think

dark sparrow
#

60 degrees yes

sleek thistle
#

so it’s 20

#

okay thanks

mortal mesa
#

@upper karma @upper karma
Thank you for your help!
It looks unsolvable using regular methods.. Sorry it was shit

upper karma
#

don't worry we had fun trying to solve it 👍

austere dragon
#

is a right triangle always scalene?

austere dragon
#

wow awesome

#

o yea i forgot about the phyton theory sry bout that

dark sparrow
#

the what

upper karma
#

o yea i forgot about the phyton theory sry bout that
huh?

glacial haven
#

python coding theory

upper karma
#

My answer here is 198.585 sq.units but the books says the answer is 103.2 sq.units how is the area of this irregular figure id 103.2 if the area of rec only 9 x 15 = 135 is already larger than 103 ?

dark sparrow
#

the circle isn't part of the shaded region

#

you're supposed to subtract away half its area from that of the rectangle

upper karma
#

Ohhhh so thats why thanks.

#

My answer here is 32.0632sq .units and in the book is 38.24 sq.units i use 3.3 as the base of the rectangle and use 6.5 height for the height of it. The diameter i use is 5.2 divide 2 for the radius and i use 1/2 pi x r squared

#

Epic

dark sparrow
#

the lower part is not a rectangle.

upper karma
#

Is it a trapezoid?

dark sparrow
#

yes