#geometry-and-trigonometry

1 messages · Page 208 of 1

dark sparrow
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it'll get you the perimeter

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notice, however, that you can carve this room up into two squares and a rectangle

robust breach
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area is the inside right.

dark sparrow
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...yes

robust breach
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how the heck do we count the inside of a square?- im sorry im stupid and I am extremely bad at math...

dark sparrow
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a square is just about the easiest shape to compute the area of...

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all area is based off of squares and rectangles

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if the side length of a square is $s$, then its area is $s \cdot s$, or $s^2$.

somber coyoteBOT
dark sparrow
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this is the reason we call things raised to the second power "squared"!

robust breach
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wha-

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I have no idea what the heck you just said... like I said I can not do math.

dark sparrow
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mmh

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...

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the person left.

supple abyss
dire rampart
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@GamerDood#9867

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rip

plucky marlin
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🇫

violet cave
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How can i calculate the area of this

dark sparrow
violet cave
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ah thanks

dark sparrow
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subtractive area calculations like this are pretty useful a lot of the time

upper karma
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whats the difference between a circle and its circumference

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there isnt one right

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a circle is the locus some distance from a set point, not the figure bounded by it becuase thats a disc?

steady sleet
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A circle is a shape

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the circumference is the length along the outside of the circle

upper karma
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a circle is formally a line though

pallid cloud
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More like a line is a circle

upper karma
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?

steady sleet
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I'd rather say a circle is a collection of points

pallid cloud
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You can consider a line as a circle with radius infinty

upper karma
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well yeah thats what i said before

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a locus some distance from a set point

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and technically a line segment or well in this case a curve is also a collection of points
my question was is there an actual distinction between a circle and circumference

pallid cloud
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The locus of the points with a constant distance to a given point

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Well yeah

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The circle is a geometrical object

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Its circumfrence is a number

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Perimeter

upper karma
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oh alright so the circumference is the length itself

pallid cloud
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What's the difference between surface and area

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Same thing

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Area=measure of surface

steady sleet
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I think you are confusing objects with their measurements

pallid cloud
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Surface is geometric object
Area is measure of the surface
Circle is geometric object
Circumference is measure or the circle

scarlet path
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I need help

pure shore
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any help

devout shell
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well use the fact they are similar triangles to help you

upper karma
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Hello! Can I get a little help? Nothing too hard

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<@&286206848099549185>

vagrant elk
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smh

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don't p i n g

devout shell
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you didn't even post a question...

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lol

vagrant elk
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^

upper karma
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Sorry D: I'm trying to find the rules but is kinda hard to find

vagrant elk
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no worries, just put your question here (or preferably in a question channel)

devout shell
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well nothing will undo the ping, so just ask it now lol

upper karma
devout shell
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how do you isolate cos(R) then?

upper karma
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Yes

devout shell
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$-56\cos(R)=16$

somber coyoteBOT
devout shell
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Isolate cos(R) for me

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I really you know how to...because how did you even get this far in geometry then without knowing algebra basics...

upper karma
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Long story...

devout shell
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isolate cos(R) please

upper karma
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Like this?

devout shell
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perfect

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that is exactly what you are supposed to do

upper karma
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Thank you very much! If I want to ask more questions, which channel should I use?

devout shell
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you can keep using this one then, since you already occupied it lol

upper karma
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:o okay

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It is okay if you correct my answers or I can only ask questions?

devout shell
upper karma
devout shell
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well no original triangle to reference

upper karma
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I can show you the one on my notebook if it's better

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But that's more exact

devout shell
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you are incorrect

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you messed up here

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580 - (576 * cos(21))

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$580-(576\cdot \cos(21)) \neq 4\cdot\cos(21)$

somber coyoteBOT
upper karma
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Then square root?

devout shell
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yes, but you have to realize why you were not allowed to do what you initially did

upper karma
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Because 576 is connected to the cos21?

devout shell
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recall order of operations

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PEMDAS

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multiplication comes before addition or subtraction

upper karma
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Trueee

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So dumb

devout shell
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so you have to multiply 576cos(21) first

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then you can do the subtraction

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then you take the square root of everything

upper karma
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Yes yes tinktonk

devout shell
upper karma
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Now comes the hard ones, the ones the ones that got my class all messed up

devout shell
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lol hardly a challenge for us though

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this will be easy to work through, but I'm not going to be the one doing most of the work, I just give pointers lol

upper karma
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It's okay! You are giving the support I needed

devout shell
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give me a minute lots of stuff happening at once

upper karma
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Take your time :0

devout shell
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perfect

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it is right

upper karma
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:D great!!

devout shell
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correct eeveeKawaii

upper karma
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hype Amazing!!!

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Thank you so much Amphy!!

devout shell
upper karma
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Have a nice night :)

upper karma
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how would i calculate the angle of a point in a plane compared to another point in a different coordinate in the same plane? like A(2;4) and B(3;7)

devout shell
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you mean like if there was a vector from (0,0) to A and a vector from (0,0) to B, what is the angle between them?

upper karma
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a line between A and B and the angle of that line

devout shell
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can you show picture of what you mean?

upper karma
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is there a tool for drawing a plane and points on it?

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or do i have to go on ms paint

solemn holly
devout shell
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use desmos lol

solemn holly
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The three circles have the same radius "r", the lines are paralel and circles are tangent

devout shell
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geogebra is good too

upper karma
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thanks

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ok, imagine a line between those two points. i want to know how to calculate that line's angle based on A looking at B

devout shell
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angle that line makes with the x axis then right?

upper karma
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yeah

devout shell
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one way is to see that theta is equal to arctan(y/x)

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so arctan(4/2) will give the angle

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well perhaps no

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hmmm

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because then arctan(7/3) would be different

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I should play with it geometrically then

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"If the slope of a line is m then the angle is θ=arctan(m)"

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looks like that's your answer, had to look it up lol

upper karma
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i'm gonna be honest. i'm bad with angles so i don't know how sin, cos, tan and arctan works

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neither θ

devout shell
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theta is common notation for the angle

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arctan means tangent inverse, arc[insert trig function] means inverse[of that trig function]

dark sparrow
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θ is just a letter

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a greek letter, as it were

upper karma
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i need to be able to be good at trigonometry to be able to make 2d games but i just suck at it so much

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i'm better with algebra

devout shell
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you learn slowly

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no one gets it right away

upper karma
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i don't understand cos, tan and sin

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how did they appear, how are they calculated

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why isn't sin(2) = sin(1) + sin(1)

devout shell
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more than we can explain over discord lol, you'll take a course on trig though and you'll learn it then

dark sparrow
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why would sin(2) be equal to 2sin(1) thonkzoom thonkzoom thonkzoom

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in all honesty, khan academy has a good trigonometry course

unkempt palm
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Ok so i rlly need help with some trig h(x) = 3 sin(2x) sin(10x) basically i get the amplitude and the two periods of the functions individually but when multiplying 2 functions how exactly does it work how is the new period determined how is the new amplitude determined etc.

dark sparrow
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uh

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well ok for starters this won't be a pure sinusoid

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second you can rewrite it using a product to sum identity

unkempt palm
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yea i tried graphing it and got a period of pi/2 which i didnt understand how the two periods related to that value

dark sparrow
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$\sin(u) \sin(v) = \frac12[\cos(u-v) - \cos(u+v)]$

somber coyoteBOT
dark sparrow
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so you get $h(x) = \frac32[\cos(8x) - \cos(12x)]$

somber coyoteBOT
unkempt palm
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im a little bit confused about the period

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because when graphing i observed a period of pi/2

dark sparrow
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indeed

unkempt palm
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and i do understand how 2 and 10 result in a pi/2 period

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not*

dark sparrow
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cos(8x) has a period of pi/4 and cos(12x) has a period of pi/6

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the "greatest common integer multiple" of these is pi/2

unkempt palm
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ok

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so the greatest common multiple is the period?

dark sparrow
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well... generally, yeah.

unkempt palm
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and whilst still on this how is the amplitude discoverd

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is it just 3

dark sparrow
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well it can't be greater than 3

unkempt palm
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because when graphing my valuse didnt go from 3 - -3

dark sparrow
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but to find the exact amplitude i'd differentiate the thing and find its extrema

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it suffices to find them on [0, pi/2]

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bc periodicity

unkempt palm
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ok

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thx this helps alot

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@dark sparrow sorry to bother but i just had one question how did you go from 1/2[cos(u-v) - cos(u+v)] to 3/2[cos(u-v) - cos(u+v)]?

dark sparrow
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huh what

unkempt palm
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sorry

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i fixed it

dark sparrow
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your thing had 3 as a coefficient

unkempt palm
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so the coeffecient becomes the numerator

dark sparrow
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what

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no

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jeez

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i just went from $3 \sin(10x)\sin(2x)$ to $3 \cdot \frac12 [\cos(8x) - \cos(12x)]$... don't overthink it

somber coyoteBOT
unkempt palm
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oh i see sorry im very new to this type of trig as i am first semester year 11 thanks so much for the help

upper karma
rustic cairn
dark sparrow
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what

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sorry, the picture is cropped too much

rustic cairn
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H

ornate shadow
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For SAS:
OM = HG S
<O = <H A
Since the angle and side are connected and we need another connected side for SAS(i.e. angle included between two sides)
HJ=OK S

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For ASA:
This time one side should be connected to the two angles. The only other connected angle to the given sides is<M and <O

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So,
<M=<O

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If by HL you means RHS,
KM=JG H

upper karma
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Hello, I'm studying trigonometry with unit cirlce and I don't understand why a cosine or a sine can be negative ? Isn't it a lenght divided by another length ? Sorry if it is the wrong place to ask this

real mulch
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it's signed length

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it conveys information about direction

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cos(x) and sin(x) are the coordinates of the point on the unit circle that you reach if you turn x radians around the origin in the counter-clockwise direction starting from the point (1, 0)

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the x-coordinate of the red point is cos(x),
the y-coordinate of the red point is sin(x)

upper karma
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Thank you so much for this explanation !

low herald
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can you guys help me out with this

If tan(x + y) = 33 and tan x = 3, find tan y.

half gull
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there's a formula for tan(x+y)

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you can find it by using formulas for cos(x+y) and sin(x+y)

low herald
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you can find it by using formulas for cos(x+y) and sin(x+y)

I tried using that but I couldn't get anywhere

upper karma
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what did you try

ornate shadow
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tan(x+y)=(tanx +tany)/(1-(tanx)(tany))

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Plug in the values of tanx and tan(x+y) to get tany

devout shell
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Easy way to think of it, area of base * height

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area of the base is a quarter circle

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Area of a quarter circle: $\frac{\pi \text{r}^{2}}{4}$

somber coyoteBOT
devout shell
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Base Area * Height = $\frac{\pi \text{r}^{2}}{4} \text{h}$

somber coyoteBOT
devout shell
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height is 10, but also check your area

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you used the formula correctly? If you did then you got the right answer

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no need to ask me if you followed the formula correctly

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your answer was?

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correct

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for regular solids, to find the volume, just remember that it will be:
(Area of the Base) * (Height)

vagrant elk
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bruh

devout shell
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why didn't you just post there though?

upper karma
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will love who ever can help me out

devout shell
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are you familiar with the definitions of the six trig functions?

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you will also need to solve for c first, how would you go about doing that then?

upper karma
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A^2+B^2=c^2

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i did that

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and got squareroot(58)

devout shell
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that is incorrect

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a=7 and b=10

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check your squaring and addition again

upper karma
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149

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then simplify that right?

devout shell
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now take its square root and you have the length of c

upper karma
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12.2

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is it 2 square root(74.5)

devout shell
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you could just leave it as sqrt(149) if you wanted

upper karma
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ok

coral terrace
upper karma
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so sin= 7/squareroot(149

devout shell
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yes, just follow the definitions of the trig functions and you will get it right

uncut pagoda
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Can anyone help me with this?

devout shell
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what is the aim of the problem?

uncut pagoda
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Trying to find the base and leg
Or two legs if that makes sense

devout shell
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are you familiar with sine and cosine?

uncut pagoda
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@upper karma

upper karma
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Yes

devout shell
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you had question?

upper karma
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Yeah

devout shell
upper karma
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sooo

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i understand to do 6^2+ b^2 = c^2

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but like how do i do that without have b or c

devout shell
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use the trig ratios to help you solve

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you have an angle and an opposite side, what could you use to find c?

upper karma
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B and A but how

devout shell
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you can use a trig ratio, as I had already stated

upper karma
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I see what you want me to do but i dont know how to do it

devout shell
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type it out then

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what do you think I want you to do?

upper karma
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65/25

devout shell
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what does that even represent?

upper karma
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Opposite and hypotenuse

devout shell
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Let's just start from the definition then.\ $\sin(A)=\frac{\text{opp.}}{\text{hyp.}}$

somber coyoteBOT
devout shell
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right? you know that is true

upper karma
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yeah

devout shell
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so we have an angle, A

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what is that angle?

upper karma
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65

devout shell
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and what is the opposite side?

upper karma
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25

devout shell
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do what do we want to solve for?

upper karma
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2.6

devout shell
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I didn't say anything about numbers, I said what are we trying to solve for?

upper karma
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so that will be c

devout shell
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$\sin(65)=\frac{25}{c}$

somber coyoteBOT
devout shell
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solve this equation for c, and that will be the answer

upper karma
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27.5

devout shell
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correct

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so now you can get b

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@upper karma you had a question about the area of a regular polygon?

upper karma
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I got an email from my math teacher that said my previous answer which the paper said was incorrect is actually correct, so I'm sorry for bothering you

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if I ever have further questions I'll ask

devout shell
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ok then lol

upper karma
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I am having trouble getting b is this right so far 36+b^2=756.25

devout shell
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you can also use a trig ratio as opposed to solving it with pythgorean thm

upper karma
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ok so i would do opposite/adjacent

devout shell
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what is that trig ratio called?

upper karma
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opposite/adjacent

devout shell
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it has a name

upper karma
#

tan

devout shell
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tan(x)

upper karma
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ok

devout shell
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you take the tangent of something, tan on its own doesn't mean anything

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it's a bad lazy habit to just write sin, cos, tan

upper karma
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oh right ok

devout shell
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because they are functions, not just words

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so you should get used to writing sin(x), cos(x), and tan(x)

upper karma
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ok.... will it be then tan(x) = 6/b

devout shell
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x is what though?

upper karma
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25?

devout shell
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but that is correct, just put in the correct number for x

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x is the angle

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wait your answer for c is wrong

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I was just going off the numbers you gave me, but like since when was 25 degrees the length of the opposite side?

upper karma
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65 is the opposite

devout shell
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opposite means opposite side...

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the only place an angle will appear is in the x for the trig ratio, the rest of the number are lengths

upper karma
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ok so

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the opposite of c is a

devout shell
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I don't even know what you are trying to say there

upper karma
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idk what im saying honestly im lost

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once u said c is wrong u lost me

devout shell
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because you used angle measures in place of length measurements

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you will have to review the trig ratios then

upper karma
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yeah i see that now but idk what to do from there

forest thunder
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are you guys talking about SOH CAH TOA

devout shell
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yes, but we are making our way through it

forest thunder
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Sin == opposite/hypoteneuse (english??)

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ok just curious

devout shell
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correct

upper karma
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I want to get c so i have to do ........ sin?

devout shell
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so how about you repost the screenshot and tell me all angles measures you have

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and tell me what lengths we are given

upper karma
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all angles are shown there

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a=6, A=65 and B= 25

devout shell
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ok, so we want c

upper karma
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yes

devout shell
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and we have a

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so write out how we would solve for c, fill in the numbers

upper karma
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would it be 6/c

devout shell
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6/c equals what?

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you have to say what it is equal to

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that is very important

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because 6/c is just some ratio, it has no meaning to me

upper karma
#

sin(x)= 6/c

devout shell
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what is x then?

upper karma
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x would be 65

devout shell
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ok so write that all out and then solve

upper karma
#

c = 6.6

devout shell
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yes

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now you can solve for b however you want

upper karma
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so b is 7.56

devout shell
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show me how you got that answer then

upper karma
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6^2+b^2=6.6^2

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36+b^2= 43.56

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b^2=7.56

devout shell
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b^2=7.56

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you need to take the square root

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because you have b^2, not b, and you want b

upper karma
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how do i take the square root out?

devout shell
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what?

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something is being squared right now, so to taking its square root will undo that squaring

upper karma
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k im back

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so b=3.78

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right

devout shell
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I guess, I can't do square roots in my head, but that sounds correct

upper karma
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c is right but b isn't

devout shell
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so then you messed up a bit somewhere or there is round off error

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you can just use tan(x) to solve for b instead if you wanted

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that should be more accurate

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wait...how did you get 3.78?

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I should have realized that was way off, but oh well catshrug

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square root does not mean divide by 2 if that was what you did

upper karma
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i just divided by half and crossed my fingers couldn't figure it

devout shell
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no...

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you know what a square root is?

upper karma
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yes but like i don't understand how to get rid of it

devout shell
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you were attempting to get rid of a square, not a square root

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to get rid of a square, you take the square root

upper karma
#

ohhhhhhhhhh

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2.74

devout shell
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that sounds more correct

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should be in that range of numbers

upper karma
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ok thanks for helping and dealing with my stupidity

devout shell
#

it's all part of the learning process, that's all, nothing stupid about it

solar shale
solar shale
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<@&286206848099549185>

dark sparrow
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@solar shale is that line labeled as "15" meant to be tangent to the circle

solar shale
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So if there is a tangent then it means 90 degree angle

dark sparrow
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a tangent is perpendicular to the radius drawn to the point of tangency.

solar shale
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Ah ok

granite canyon
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<@&286206848099549185>

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;3;

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can anyone guide me through this

dark sparrow
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(in the future, post your q, then ping helpers if you don't get any replies within 15 mins)

granite canyon
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oh

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srry

dark sparrow
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well what have you tried so far

granite canyon
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uh

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I know that you have to divide 360 by 4?

dark sparrow
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no, you never "have to" do anything

granite canyon
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o

dark sparrow
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don't think in terms of "do i have to do this"

granite canyon
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ok

dark sparrow
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think in terms of "if i do this, what'll that give me?"

granite canyon
#

that makes more sense

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uhh

hallow smelt
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so my original equation is r=2sin(x)

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I get how we wind up x^2+y^2-2y=0

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I don't get how they complete the square of that to graph it? how can you complete the square with three terms

dark sparrow
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complete the square on y^2 - 2y

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x^2 is already a completed square

hallow smelt
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negative b over 2 a right? 2/2

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x is already a completed square? because its the only x term?

dark sparrow
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no

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x**^2** is already a completed square

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because there is no x^1 term

hallow smelt
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oh ok

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cool I see it now

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my teacher wrote it like this though

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(x+0)^2 + (y-1)^2 = 1

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is there any reason to write x like that?

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is x^2 wrong?

dark sparrow
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maybe to accentuate that 0 is the x coord of the center, but not for any other purpose

hallow smelt
#

they want me to go from rectangular coords to polar. x^2 + y^2 = 9 I know x^2 + y^2 = r^2 so r = 3

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how do I get the angle though?

dark sparrow
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r = 3

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that's it

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r = 3 describes the circle of radius 3 centered at the origin

cloud merlin
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im pretty sure its gona be like square root of 3 to the power of 2

devout shell
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if only it explicitly said it was a square, then that would make things easy lol

spark stag
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@cloud merlin not quite

cloud merlin
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it is a square

spark stag
devout shell
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there shouldn't be any square roots in the final answer lol

spark stag
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(sorry for the terrible drawing)

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and yeah its regular and 4-sided, so its a square.

devout shell
#

the answer for this is pretty easy to find lol

spark stag
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saying its "pretty easy" isnt exactly helping

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although man, TAing would be a lot easier if so

devout shell
#

thought he figured it out already

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I'm thinking he knows what to do at this point though

cloud merlin
#

look ill draw it out

devout shell
#

did you get the answer though?
or you still thinking that it's going to be 3 m^2?

cloud merlin
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nvm

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its square root of 18

spark stag
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erm

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the side length is the square root of 18

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whats the area?

cloud merlin
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square root of 18 to the power of 2

spark stag
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can you simplify that?

cloud merlin
#

here let me show you

spark stag
#

$\sqrt{18}^2$

somber coyoteBOT
spark stag
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i just want you to rewrite that in simpler form

cloud merlin
spark stag
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yes, your work is correct

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but your answer can be simpified

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if we take the square root of something, and then square it, what are we left with?

cloud merlin
#

i gtg ill be back later

spark stag
#

.

#

$\sqrt{18}^2 = (18^{\frac{1}{2}})^2 = 18$

somber coyoteBOT
spark stag
#

and then you need a unit of m^2

#

so, the area is 18m^2

#

that rule should intuitively make sense too: if x*x = some number

#

then the square root of that number is x

#

and x^2 = x*x = that original number

#

in other words, $\sqrt{18}^2 = \sqrt{18}\times\sqrt{18} = 18$

somber coyoteBOT
spark stag
#

since sqrt(18) is the number that, when multiplied by itself, gives 18.

sleek knot
#

To find the height of a pole, a surveyor uses a theodolite. The theodolite is 4 ft tall. The surveyor stands 140 feet away from the base of the pole. Then she measures the angle of elevation to the top of the pole to be 38o. What is the height of the pole? Round the answer to the nearest foot.

#

can somebody help me

devout shell
#

well the height of the pole will be given by x+4, but then the question is what is x?

#

assumption: that is a right triangle

#

not explicitly given that it is a right angle but looks close enough so that works for me

#

anyways, we have an angle and a side given to us, and we want to find another side, what trig ratio will help us out?

sleek knot
#

yeah im just unsure how to start the problem off

#

trig ratio?

devout shell
#

trigonometric ratio, (sine, cosine, tangent, etc...)

sleek knot
#

oh those three

#

we usually do sin in class

#

isnt like sin 44 = 4/140

devout shell
#

where did you get that picture though? says angle of elevation is 38 but then there is 44?

#

then it seems like you added in 38 on your own?

sleek knot
#

oh i forgot about the 38

devout shell
#

can you give me the correct graphic then

sleek knot
#

thats the picture

devout shell
#

because 44 degrees was never given, but it's there

sleek knot
#

its in the picture

devout shell
#

your statement says 38 degrees

sleek knot
#

yeah in the question does say that

devout shell
#

then the picture puts the 38 on the hypotenuse as if it was a distance measurement

#

so I'm not very sure what is the correct angle to use

sleek knot
#

lets just use 38

devout shell
#

ok so scrap the 44, and replace it with 38, that will change the answer of course

sleek knot
#

so sin 38 = 4/140 ?

devout shell
#

where is the 4 coming from

#

we want x

sleek knot
#

4 ft

devout shell
#

x is nowhere in that equation

sleek knot
#

oh

#

so sin 38 = x/140 ?

devout shell
#

4ft is not even part of the triangle we are looking at

#

what is the definition of sine?

sleek knot
#

sine of an angle is opposite/hypotenuse

devout shell
#

how is 140 the hypotenuse? your picture clearly shows that 140 is a leg

#

but you are correct with your definition of sine though

#

just putting in the wrong thing

#

currently we don't have the length of the hypotenuse

#

perhaps we should try a different trig ratio

sleek knot
#

wait 38 would be teh hypotenuse

#

the*

devout shell
#

it said 38 was an angle measure

sleek knot
#

then how are we suppost to find the hypotenuse?

devout shell
#

38 is impossible anyways given one side is 140

#

we don't need the hypotenuse, we can always use a different trig ratio, unless the only one you have been taught is sine

sleek knot
#

we have been taught* cos and tan but we today we used sin

devout shell
#

what is the definition of tangent and cosine?

#

perhaps considering other trig functions will be useful because we see that sine is not going to help

sleek knot
#

cos = adjacent/hypotenuse and tan = opposite/adjecent

devout shell
#

so out of the two only one does not need the hypotenuse

#

we have one of the legs and we want the other leg, so let's use..?

sleek knot
#

tan

devout shell
#

let's use tan(x) because then we won't need the hypotenuse

#

so what would the equation be?

sleek knot
#

tan 38 = x/140 ?

devout shell
#

no need to be doubtful when you literally followed the formula, you are going to be correct when you apply the formula properly

cloud merlin
#

?

sleek knot
#

yes

cloud merlin
#

need help?

sleek knot
#

yes

devout shell
#

solve for x for me please

#

I've been helping though

cloud merlin
#

sure do you guys understand triganomatry

devout shell
#

yes

sleek knot
#

i dont

dark sparrow
#

dsghklf

cloud merlin
#

ok wait a little

sleek knot
#

not a big math guy

dark sparrow
#

can we please like

sleek knot
#

more into science

dark sparrow
#

not mangle the spelling of "trigonometry" like that

#

please

sleek knot
#

x=109.37998771

dark sparrow
#

granted i've seen worse but

devout shell
#

you know the definitions of the ratios though, we are just helping you to see which one to use

sleek knot
#

yeah

devout shell
#

ok, so it said round to nearest foot, so please do that

sleek knot
#

109 ft

devout shell
#

perfect, now the final step

#

the length of the pole is given by what?

#

look at the figure if you are unsure

sleek knot
#

what do you mean given by like the elavation?

devout shell
#

they wanted the length of the pole, which is on the left side of the figure

sleek knot
#

so x

devout shell
#

is that all?

#

x is only part of the pole

cloud merlin
#

Probably this

sleek knot
#

but in the problem it doesnt say anything about 44 degress

#

@ eatsleepanime

devout shell
#

this is a strange picture, you sure this is straight from your book?

sleek knot
#

not from the book she send us a link to a google document

devout shell
#

I'm pretty sure that the length of the pole is x+4

cloud merlin
#

Look at the right

sleek knot
#

4 ft on the right

cloud merlin
#

That acute angle

devout shell
#

but original problem said use 38 degrees

#

but here's the thing

cloud merlin
devout shell
#

you need to add 4ft

sleek knot
#

so 109 + 4 = 113

#

ft

cloud merlin
#

Wait let me get my calculator

devout shell
#

that is the answer, yes

cloud merlin
#

The answer is

devout shell
#

don't use 44 degrees

cloud merlin
devout shell
#

the problem gave a different angle measure

cloud merlin
#

Just change the 44 to any other angle

#

Also this works with degrees so calculators have to be on degree mode

devout shell
#

let's not make this problem any more confusing than the graphic already is by introducing a formula that uses two trig ratios

cloud merlin
#

Well cos can be easily represented with sin

#

And so could tan

sleek knot
#

so the answer to that problem is 113 ft correct?

cloud merlin
#

Idk I don’t have my calculator

devout shell
#

given what you told me, yes

#

again that picture is the worse thing ever, because it has two angle measures and one is not even labeled properly, but we went off of what the problem said

#

but do you see why the height of the pole was x+4?

#

and not just x

sleek knot
#

yeah

#

thank you for the help very much

#

i understand it much better now

devout shell
#

we need a better picture to properly show you things lol, but you can see that it's not always hard and fast about what ratio to use

#

you take a look at what you are given and choose the ratio that utilizes the givens to find the unknown

sleek knot
#

i also have 1 more problem I did but I'm unsure if its correct if u could check it

devout shell
#

hopefully that one has a better picture GWcentralPikaLUL

cloud merlin
#

sin is the best like all the other trig functions dont need to exist

devout shell
#

what?

sleek knot
#

tan64=x/7
x=14.35212689
x=14
wait i need so round to the nearest tenth so it would be x=14.4

cloud merlin
#

all of them could easily be represented by sine

#

sin

devout shell
#

that would overcomplicate things

cloud merlin
#

still

devout shell
#

why sine? it could have been equally just cosine then

cloud merlin
#

sin is the easiest to calculate

#

and easy to understand

devout shell
#

what? um no, all of them are fairly easy to understand

#

you are correct nickk

#

I'm not sure about rounding; it's whatever your teacher wants

sleek knot
#

wait i need so round to the nearest tenth so it would be x=14.4

devout shell
#

plus if you get rid of everything except sine, then the unit circle would not be nearly as nice

#

ok, with rounding, you are still correct

last flume
#

All trigs are easy tbh

cloud merlin
#

we dont need to argue

#

but sin is the best

sleek knot
#

thank you all very much for the help I understand this very much better

cloud merlin
devout shell
#

that is overly complicated

cloud merlin
#

thats what people who dont understand say

devout shell
#

then how does the unit circle look for you

cloud merlin
#

what

devout shell
#

that's why lol, once you realize the implications of this to the unit circle you will stop asserting that sine is the best

cloud merlin
#

it is

#

its the simplest to understand

#

well maybe cos is also easy

#

but sin is just cool

devout shell
#

sure, but it's not the end all be all

cloud merlin
#

what does that mean

devout shell
#

it's not the ultimate weapon

#

you need other tools

cloud merlin
#

sure

#

does anyone know how to calculate sin

devout shell
#

Now you ruined the simple identity of: $\sin^{2}(x)+\cos^{2}(x)=1$

cloud merlin
#

like exact value?

hearty barn
#

yees

somber coyoteBOT
hearty barn
#

sin 1+ sin 1 = sin 2

#

jkjk

sleek knot
cloud merlin
#

no shit

sleek knot
#

for this problem would i also have to use tan?

cloud merlin
#

forget tan

#

its stupid

devout shell
#

well what are you given?

cloud merlin
#

overcomplicates things

devout shell
#

stop please

sleek knot
#

the problem is just "Find the value of x, rounded to the nearest tenth."

devout shell
#

we are working on something

cloud merlin
#

even pi can easuly be calculated with sin

hearty barn
#

Two questions at the same time?

#

@sleek knot ping me in one of the question channels

#

Make sure its empty

devout shell
#

no man, don't leave me to argue about ratios lol

sleek knot
#

which channel idk

#

i just realized i came into pre uni and this is highschool stuff

devout shell
#

well looks like he's gone....so let's continue

cloud merlin
#

That’s why sin is best

#

It’s a sick trig function

devout shell
#

please stop, I have a question I am working on with someone

cloud merlin
#

Well forget about that

sleek knot
#

we can argue after this question because its the last one

devout shell
#

but what side are you looking for in the problem?

#

and what side is given to you?

sleek knot
#

11 28 and x

#

idk why theres just a little 38 in there

devout shell
#

tell me what side x corresponds to

#

is it a leg or a hypotenuse?

sleek knot
#

x is the hyp

hearty barn
#

I'm here

#

@devout shell whose question you want me to handle?

devout shell
#

I'll let wolf take the lead lol

sleek knot
#

the only thing for hard is, is just to choose the correct treg ratio

#

but i sort of understand now

devout shell
#

stage is all yours

hearty barn
#

lmao it's fine if you wanna

devout shell
#

no no, lol you're eager for it so be my guest, need to get back to work lol

sleek knot
#

alright so would it be tan?

hearty barn
#

Whats 32?

sleek knot
#

not sure its just there

cloud merlin
#

anyone watch anime?

plucky marlin
#

yes

cloud merlin
#

xD

plucky marlin
cloud merlin
#

one piece and stience gate are sick

sleek knot
#

also sorry if i distracted you of your work @Amphy⚡#0697

plucky marlin
#

i didnt see one piece tho

hearty barn
#

@cloud merlin Warning, don't spam here

cloud merlin
#

then watch it

#

spam?

#

im not

devout shell
#

nah I do this on my own time, you're good

sleek knot
#

thanks for the help again

plucky marlin
#

no problem

hearty barn
#

Let's ignore 32 for now?

sleek knot
#

yeah lets do that

devout shell
#

but anyways someone is attempting to help you, you should move into a help channel and lock it to keep spam away

hearty barn
#

lel true

#

It's fine lets work here

sleek knot
#

so would i use tan or other treg ratio?

hearty barn
#

We can either use the ratio 11/x or x/11

#

Right?

#

Because we have no idea about the other side

sleek knot
#

yeah x/11 because x is the hyp pretty sure

hearty barn
#

Yee

sleek knot
#

so tan 28 = x/11

hearty barn
#

And the angle provided to us is 28

#

YES

sleek knot
#

lemme use a calculator real quick

hearty barn
#

==calc tan 28

#

,w calculate tan 28

somber coyoteBOT
hearty barn
#

here you go

sleek knot
#

x=5.84880374

#

round do the nearest tenth so 5.8

hearty barn
#

COOL

#

it's done

sleek knot
#

thats all i needed thank you for the help

plucky marlin
#

np

hearty barn
#

Want me to kick your banana, @plucky marlin ?

plucky marlin
#

lol just kidding

hearty barn
#

xD all cool

sleek knot
#

have a great night (or morning wherever yall live at)

hearty barn
#

,w time India

somber coyoteBOT
devout shell
#

wait the missing side was a hypotenuse

hearty barn
#

Aye

#

But I wasn't sure if 32 is thhe side length

devout shell
#

but hypotenuse is longest side and it's 5...? but a leg is 11...so that's an impossible triangle lol

#

some random ass 32 included because the teacher sucks at making graphics, but you guys solved for the opposite side lol

#

@sleek knot you found a side that you didn't need to lol. I think the graphic confused him

hearty barn
#

OH

#

OHHH FUCK

#

AAHHHH

devout shell
#

here's your chance to make it right lol, go for it lol

hearty barn
#

cos 28 = 11/x
x = 11/cos 28

#

,w \frac{11}{\cos 28}

somber coyoteBOT
hearty barn
#

@sleek knot @sleek knot @sleek knot @sleek knot @sleek knot @sleek knot @sleek knot

#

I MADE A MISTEKKKKKKKKKKKKK

sleek knot
#

oh

#

thats no bueno

#

what is it

#

so i change it before the teacher sees it

hearty barn
#

It's cos and not tan

sleek knot
#

ok ima do that thanks

cloud merlin
#

It’s just this

#

Here are 2 answers

#

With tan it’s this

devout shell
#

why would you do that to yourself?

cloud merlin
#

do what?

devout shell
#

making it overly complicated for no reason lol

cloud merlin
#

I do the math the way I understand

#

I don’t memorize

clear haven
#

uh

#

dunno what to say but

#

keep an open mind ? lol

dark sparrow
#

what is even being done there

cloud merlin
#

you guys want me to explain them?

#

the third one is pretty basic but i can explain the sin and cos

dark sparrow
#

i mean it's not even clear what you're going for there

#

can you post the original problem you were doing

dark sparrow
#

$x = \frac{11}{\cos(28^\circ)}$

somber coyoteBOT
dark sparrow
#

which even appeared in your work

cloud merlin
#

Here this is the other one explained

oak minnow
umbral snow
#

Please see #info on helper pings

dark sparrow
#

have you done what the hint tells you to do?

oak minnow
#

yeah I made a line that goes through B and D

dark sparrow
#

okay

#

so this gives you two triangles

#

ABD and CBD

#

are you able to calculate the area of each?

oak minnow
#

BCD

dark sparrow
#

the vertices of a triangle can be listed in whatever order unless you're making a statement about similarity, which i am not.

#

that's beside the point, anyway.

oak minnow
#

...

#

ok

dark sparrow
#

there are two triangles there

#

are you able to calculate their areas?

oak minnow
#

what if I say no?

dark sparrow
#

then we're going to step back from the problem for a moment

#

but until you say yes or no, i'm not going anywhere.

oak minnow
#

well im 50/50 with that

dark sparrow
#

what do you mean 50/50

oak minnow
#

my guess would be 1/2basinB

dark sparrow
#

i can tell that you wrote sin*B there. that's inappropriate, because sin B is not the product of B and something called "sin".

#

(and it should be sin(B) anyway)

#

but that's beside the point

oak minnow
#

I dont care, I just want to know how to do it

dark sparrow
#

ok, you've blurted out a formula. you should probably give it some context, such as describing what the variables in it represent and what its output is meant to be

oak minnow
#

nvm i figured it out

#

0.5 * 8 * 9 *sin(A)

dark sparrow
#

that's the area of ABD, yes

#

are you able to calculate the area of the other triangle?

oak minnow
#

hmm

dark sparrow
#

if you were able to do that for the first triangle, then you should also be able to do it for the second.

oak minnow
#

half * 6 * 6.76 * sin(C)

dark sparrow
#

indeed

#

so now are you able to calculate the area of the entire shape?

oak minnow
#

how do I know where to put the side letters?

#

like u know how this for eg

dark sparrow
#

the what letters?

oak minnow
dark sparrow
#

you should not be concerning yourself with sticking to one particular set of labels and attaching them to every triangle you see

oak minnow
#

well thats what ive been doing

dark sparrow
#

you should instead understand visually what elements of your triangle the formula involves

oak minnow
#

i dont know

#

if it was something like ABD how would I state that

#

with the small labels

dark sparrow
#

okay so look

#

the formula you know as 1/2 ab sin(C) involves two sides and the angle between them.

oak minnow
#

yes

dark sparrow
#

the exact names of those sides and the angle DO NOT MATTER

#

and my point is you should not attach yourself to any particular names

oak minnow
#

so I could in between A and B i could put small a?

dark sparrow
#

??

oak minnow
#

nvm you wont understand what im trying to say

#

ok so for C) it would be ABD + BCD/CBD

dark sparrow
#

i don't know, would it?

dark sparrow
#

no

#
  1. Requesting or offering the exchange of money for completing homework assignments is a bannable offense.(modifié)
#

<@&268886789983436800>

#

your problem, not ours

upper karma
#

Ann is french! TIL

#

This is why she has the Sophie Germain aura!

half gull
#

I think she isn't even if she is almost fluent in french

dark sparrow
#

you're right, i'm not french

#

and i'm pretty far from fluent in french too 😛

radiant parcel
#

ann's not french

#

your french is p decent tho from what i've seen

dark sparrow
#

my french is at the level where i can shitpost to some extent but can't read real french literature for shit

half gull
#

most of french people can't read french litterature when it's old

#

maybe not "cant read"

#

but have difficulties to understand a lot of sentences

dark sparrow
#

do you have any you could recommend me that isn't like that 😂

half gull
#

No I don't read a lot of books

#

And I don't think it exists x)

#

french writers love to use words that nobody uses in common life

#

maybe some books of Andrée Chedid because she's a recent writer

gritty siren
#

🤔

autumn kestrel
#

how do you solve this one? I know how to find area of a triangle but I’m not sure how to apply it

half gull
#

whats the value of x in terms of theta?

#

and the value of y in terms of theta?

trail minnow
#

the area of the triangle is xy/2

#

just solve for x in terms of theta and y in terms of theta and then plug

autumn kestrel
#

arent x and y in terms of theta just sin theta and cos theta or

#

ohh nvm i see

half gull
#

its 4sin(theta) and 4cos(theta)

trail minnow
#

yeah divided by two

swift ice
#

not 4sincos

#

its 8

#

@autumn kestrel its C not D

autumn kestrel
#

yeah I got it

#

I just put D because I had to guess

oak minnow
dark sparrow
#

which part?

#

a i, a ii, a iii, or b?

#

@oak minnow

#

...hello?

oak minnow
#

a ii, a iii and b

#

@dark sparrow

dark sparrow
#

ok what's holding you up on a ii

#

what have you tried and where are you stuck

oak minnow
#

with a ii i cant seem to get it

#

i used the heron's formula as well

dark sparrow
#

heron's formula?

#

how are you using heron's on that

oak minnow
#

it gives us 3 sides?

dark sparrow
#

tell me, what shapes does heron's formula let you find the area of?

oak minnow
#

perimeter of something

dark sparrow
#

no

#

read my question

what SHAPES does heron's formula let you find the area of?

oak minnow
#

right angle triangles?

#

idk

dark sparrow
#

no

#

how are you using this formula if you don't even know what it applies to????

oak minnow
#

i used it on a right angle triangle and got the right answer

dark sparrow
#

i mean that's overkill

#

way overkill

oak minnow
#

how?

dark sparrow
#

because there is a MUCH SIMPLER way to find the area of a RIGHT triangle.

#

what you did is the mathematical equivalent of using a sledgehammer to hammer a nail.

oak minnow
#

i made sure i was on the safe side

dark sparrow
#

and my other point is that heron's formula is a formula that lets you find the area of a TRIANGLE. but QBCR is NOT a triangle.

#

QBCR is NOT a triangle and heron's formula applies ONLY to triangles.

oak minnow
#

we can turn it into a triangle cant we?

dark sparrow
#

you don't need to turn it into anything

#

it is a trapezoid

#

go review your area formulas.

oak minnow
#

ok so theres 0.5 * b * h

#

0.5 * bc * sin(A)

dark sparrow
#

no

#

no

#

no

oak minnow
#

0.5 * ac sin(B)?

dark sparrow
#

you CANNOT just blurt out formulae without saying WHAT THEY APPLY TO.

#

if you don't know what a formula applies to then you DO NOT KNOW THE FORMULA.

oak minnow
#

those are the formulas, no?

dark sparrow
#

if you don't know what a formula applies to then you DO NOT KNOW THE FORMULA.

#

if you don't know what a formula applies to then you DO NOT KNOW THE FORMULA.

#

if you don't know what a formula applies to then you DO NOT KNOW THE FORMULA.

#

if you don't know what a formula applies to then all you know is a jumble of symbols.

#

,rotate

somber coyoteBOT
dark sparrow
#

you should make this kind of infobox for EVERY SINGLE FORMULA YOU ENCOUNTER.

oak minnow
#

what would apply to a ii

dark sparrow
#

you need to identify the shape that QBCR is before you can say what applies to it.

oak minnow
#

how do I identify it?

dark sparrow
#

you should know all of the various types of triangles and quadrilaterals

oak minnow
#

so you say "you should know" instead of telling me a proper explanation

dark sparrow
#

sorry m8, if you don't know what say a square or a parallelogram or a trapezoid is then there is nothing i can do for you

oak minnow
#

what

#

i know what those are

dark sparrow
#

then you should be able to identify a square, parallelogram, trapezoid, etc. when you see one

oak minnow
#

;/ ok

#

could you tell me how to apply the numbers into a formula?

dark sparrow
#

no, because that is something you really should know by this point. if you are unable to plug numbers into a formula then you will not get anywhere at all

oak minnow
#

yeh ok but what is the formula of a trapezoid?

#

do you know?

dark sparrow
#

"the formula of a trapezoid" makes no sense

oak minnow
dark sparrow
#

the most commonly used formula for THE AREA OF a trapezoid is A = 1/2 (a+b) h, where A is the area, a and b are the bases and h is the height.

oak minnow
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yeah still dont know how to find the height

heady juniper
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modulus of ai<=1

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ai is real

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i got kinda far

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but the proof is kinda sketch

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i assumed for k

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then for k+1

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i used compound angle

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and absolute value of cosine

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would appreciate if someone could provide a more formal proof

weary vine
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Let P(N) be the next statement: sin(x1+x2+...+xN) = a1 sin x1 + ... + aN sin xN, where every a_i satisfies |a_i|<=1
P(1) is true: sin(x) = 1*sin x
P(2) is true: sin(x1+x2) = sin x1 * cos x2 + cos x1 * sin x2 = a1 sin x1 + a2 sin x2
Suppose that P is true for some m>=2
Then sin(x1+x2+...+xM) = a1 sin x1 + ... + aM sin xM
P(m+1) is the following:
sin(x1 + x2 + ... + x[m+1]) = a1 sin x1 + a2 sin x2 + ... + aM sin xM + a[m+1] sin x[m+1]
But sin(x1+...+xM+x[m+1]) = sin((x1+...+xM) + x[m+1]) = sin(x1+..+xM) cos x[m+1] + cos (x1+...+) sin x[m+1]

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sin and cos will always be somewhere inbetween -1 and 1

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If you multiply two numbers absolute value of which is less than or equal to one you will end up with the number which abs is <= 1

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Blah blah blah if P(m) is true P(m+1) is true

heady juniper
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thanks dord

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i was struggling with justifying my conclusion at the end

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would it be better to call cos xK+1 a number Ap?

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or would that lose generality?

weary vine
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And since
P(1) & for every m P(m)->P(m+1) you get for every n from naturals P(n) is true

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I'd suggest calling every cosine something like a_i

heady juniper
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"P(1) & for every m P(m)->P(m+1)"

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does this just mean true for 1

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and if true for m true for m+1?

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then true for 2,3........

weary vine
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Well, P(1) is true since sin x = 1 * sin x

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And since from P(m) follows P(m+1) using math induction you get that for every natural number P(m) is true

heady juniper
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ok

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i see now

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thanks for the help dord

weary vine
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Sure

dark sparrow
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@heady juniper i can't read your thing well

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is it meant to be $\sin\left(\sum_{i=1}^{n} x_i\right) = \sum_{i=1}^n a_i \sin(x_i)$

somber coyoteBOT
heady juniper
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yes

dark sparrow
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right

upper karma
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@dark sparrow is the 🐐

dark sparrow
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the what?

heady juniper
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goat?

idle bloom
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Goat yes

daring zealot
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Forgive the terrible paint job 😛 How can I calculate all the points on the yellow curve around the circle given the radius and angle? I'm working on a 2D game and need all the yellow pixels stored in an array.

dark sparrow
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wdym all of them