#help-10
1 messages · Page 292 of 1
so -1 here?
do you mean like cast rule
?
sry idont get this
cot is identity for what
1/tan
and tan is the identity for what
sin x cos?
tan = sin/cos
1/tan = cos/sin
so there's an angle where cos/sin = -1
when does cos/sin = +-1?
what special triangles have both adjacent and opposite sides the same?
45-45-90
2 and 4
what angles would give us 45 45 90 triangles in those quadrants?
sohcahtoa
sin = opposite/hypotenuse
what type of triangle you think we need for sin to be 1?
dont none of them give that
opposite/hypotenuse = 1 means opposite = hypotenuse. so we can still use a 45 45 90.
sin 90 = 1, right. like i said, sin is the y-axis of the unit circle/triangle.
how do i use the 45 45 90 in this case
imagine theta is our angle, ad we know that in this case sin theta = 1
crap hold on
its been so long since i had to use triangles
we are moving to radians tmrw
is it going to be easier then
i actually cant really think of a way to visualize sin theta = 1 with triangles and the opp/hyp definition
sorry
that’s okay
i’m going to skip this and move to radians
is it easier for you to explain with radians then?
if i can use the unit circle, then yes.
https://www.mathsisfun.com/algebra/trig-interactive-unit-circle.html maybe this might help? it at least shows how the triangles and the circle are related.
Only your teacher knows the answer to that
could you try explaining the values
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i dont rly understand what i have to prove here apart from commutativity of addition
i mean ii) and iii) here already imply that this algebra is a ring iff the addition is commutative, no?
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so thats the volume of the sphere
it has a density of 0.9 kg/m^3
multiply that by the volume and you should get the mass
Uhhh 2748
Idk😭
I don't think that's the weight of the air
Oh wait kilograms
Idk how much that is
idk
in theory yes
cant you submit it here
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how do I solve this? (sorry for rotated photo)
,rccw
first you'll need to find the angle AOB (considering O is the center of the circle)
well, technically thats the answer
in radians
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How to do 22b) and 22c) ??
Also 23b)iii)
how did you find angle BEC?
BEC = CFB
the answer to this is a null set
{} or phi
Thx
how do you know that?
Do you know this?
they haven't provided any info
Same way AEB = BDA we learnt this in 9th
2 triangles sharing the same side have same corresponding angle in a circle
this <@&286206848099549185>
noooo. its not true
who told you that?
there isnt any info given. you cant just assume
brother its property of circle
do you see the 2 triangles in EADB
i'll show you one example. one sec
you can see 23 degrees
AEB = ADB
they share 2 same points
what grade are you in?
Tell me how are C and D angles same?
@dawn vessel
they have the same side AB
or am i trippin
Ok, first of all that is not a proper circle, second the lines arent straight so when you use protractor you would get different results, wait lemme google it for you
nice
nono. i get it
the last time i did circles was 3yrs ago
its hard to remember
now that i do
yes
mb
im sorry
so yes
good
its fine, happens
so. angle EAB is 90
cuz in triangle EAB, you know E and B. so A is 180 - those 2 angles = 90
since EAB is 90, ECB is also 90
thats c) done
@dawn vessel
now for b)
you can use the quadrilateral ABCE. you know E, A and C. you can find B
does this help?
correct
ight thx
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why is r=4?
Because it's a circular arc centered at the origin. It's pretty clear that r goes from 2 to 4
actually im not very clear on polar coordinates
so is r supposed to be a radius
Yeah
oh
🗿
well that was very stupid
then why isnt the lower limit 2 if we apply the same logic
my prof did this
Oh they're tryna find the pink line
The equation of the pink line
x = 2
rcos(θ) = 2
Since x = rcos(θ)
oh is it cause now we do polar coords so we cant take x
Mmhm
There's no vertical line at x = 4
then 4secθ
The region is bounded by a circular arc (the red curve) on the right sode
It's not a vertical line
so i take the arc instead?
Well yeah
r = 4 on polar coordinates is the arc
Well
The full circle
But the arc in this context as a bounding curve
Here hold on
okie
i think i kinda get it now
Yeah I made the full bound. Desmos is being a bitch and won't let me graph the stupid horizontal line but there you can see the region
Hm
Gonna dig deep into my brain for this because I kinda willfully forgot how to do some of this lmao after a month of pure mental torture
θ obv starts at 0
Yeah
Well actually
No you can just use pythag
The upper bound is arccos(2/4)
how did you know the h is 4
The red curve is a circular arc of radius 4 to any distance from the origin to any point on the red curve has to be 4
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HOW DO YOU FIND THETHA
😢💔
when is value of sin equal to root 3/2
huh
They are just known identities. Look at this .
how in the world am i supposed to memorize that for a quiz
hello no need to fear macro is here
so with this it is simple trigonometry and equations
Mr. Macro
we can use this formula to solve for theta by rearranging the formula, but be for so we must substitute the given values
$Tan(\theta)=\frac{(\frac{(\frac{\sqrt{3}}{2})}{(\frac{1}{2})}$
Mr. Macro
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
oo
how do you know you need to use tan
$\tan{\theta}=\frac{\frac{\sqrt3}2}{\frac12}$
silly bot
ok have you learned basic trig?
yes
i know how to find them
but i dont know how to find the missing angle
using the sin cos tan thing
ok wait i have to fix the bot
okay
$Tan(\theta)=\frac{(\frac{(\frac{\sqrt{3}}{2})}{(\frac{1}{2})}}$
Mr. Macro
$Tan(\theta)=\frac{(\frac{(\frac{\sqrt{3}}{2})}{(\frac{1}{2})}}$
```Compilation error:```! Missing } inserted.
<inserted text>
}
l.52 ...rac{(\frac{\sqrt{3}}{2})}{(\frac{1}{2})}}$
I've inserted something that you may have forgotten.
(See the <inserted text> above.)
With luck, this will get me unwedged. But if you
really didn't forget anything, try typing `2' now; then
my insertion and my current dilemma will both disappear.```
u learn the unit circle before sohcahtoa??
yes 😢
my teacher is a bit silly
he thinks we remember everything from last year
but i forgot
maybe im the silly one
FungusDesu
there
but why tan
what about sin
given tan = opposite \ adjacent
that has oppisite
$Tan(\theta)=\frac{(\frac{\sqrt{3}}{2})}{(\frac{1}{2})}$
Mr. Macro
OHHH
when we divide tan we must inverse it
i thought that was the only step
LOL
so divide the other side with tan?
how do you do sin inverse
$\theta=Tan^{-1} (\frac{(\frac{\sqrt{3}}{2})}{(\frac{1}{2})})$
Mr. Macro
ooooo
ok i shall now do it the sine way
well i since
all the sides are given
we could use cos, sin or tan
wait let me try for cos
ok
if one of the sides was negitive would i have to change the side to a positive
or does that make no sense
ohhh like if the measurement of one side is forsay -5
yes
yes you would have to use -5
unit circle
whats a terminal arm
😟
also use this
oh remember the saying Soh Cah Toa
yes
and the rule how opposite angles are equal
no no not opp
opposite angles on a parallel
When any two straight lines intersect each other, there are different pairs of angles that are formed. The angles that are directly opposite to each other
this
wait which are you solving
💀 ive never learnt unit circles
me too
i was sick on that lesson
wait wont it just be the same coordinates but oppisite signs
ima quickly learn it and try to help
nice
but how
what is a number plane
-4
yes
its flipped like a mirror
the question says pi - thetha
180 - 60
120
so the one with the smiley face
help
Idk <@&286206848099549185>
😢
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hello
i made a script in matlab for a predator-prey model
i just need something explained to me
so these are 3 graphs I made from 3 sets of inputs
the first being 4000 prey, 80 predators
second: 5000, 100
third: 200, 50
The second and the third graphs make sense, the first absolutely makes no sense to me
why did that happen?
without the script itself we cannot really know much
sure 1 min
Seems like a fixed point kinda thing
The second graph is just a weird way to plot a limit cycle
Im not the best at differential equation, but it has to do with that kinda stuff
It makes sense if you think about it
the cycle seems pretty weird actually. The populations should tend to the stability point, not oscillate so wildly
Do you have some kind of time delay
well its a very basic model with simple differential equations
yeah but they dont look like it would be correct at the most basic level
Originally, let's assume you have a (virtually unlimited) amount of prey and 1 predator
predator has free reign so it multiplies
i built the script using eulers method
until the prey is depleted enough, where you have k prey, n predators, and the n predators start competing
then the growth starts being slower, until it stops growing
@lone echo that seems to happen clearly in images 2 and 3 but i dont understand how 1 happened
at that point, you have a stable k2/n2 relation between prey and predators
just from arbitrary values of 4000 and 80
no, because in your case the predators keep multiplying even after competing way too much for survival, so both get almost extinct. That doesnt happen.
in image 3 yes?
your oscillations are constant tho
oscillations should converge to 0 as the population gets closer to the stability point
Something along these lines
true, this model is intentionally unrealistic
from what ive learned in class to make it realistic we add another factor to the diff eqs
to achieve that image
fair enough
but for right now in this assignment I have to explain the failures of this model i showed you
so far ive got what you said, but there is something else related to that first image
I dont understand why it occured that way
okay, your problem is with the graph that represents a straight line, correct?
yeah
which is 4000 prey, 80 pred
if I change it to 4100, 80 or 4000, 70 it looks more normal with oscillations
but for some reason at specifically 4000,80 it produces those straight lines
can you represent, on the pop vs time graphs, the predator multiplied by 1000?
like 4000, 8000?
(or by whatever factor makes both pops be in the same order of magnitude)
because on these kind of models, the important factor is not "how many" you have of each, the important factor is the proportion
okay, that was a misunderstandingç
i'm not asking you to introduce more predators
i think that apparent rise in predators at the beginning is misleading btw, because the graph starts at t=1
im asking you to represent, instead of the number of predators, 1000 times the predators that there are
im confused
let's say oyou have 4k prey and 40 predators
represent the 4k prey, and tell it to represent 100 times whatever predators it has
in other words, change the scale for the pred graph
or represent them in different graphs
so you only have prey vs time in one, and predator vs time in another one
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can someone check this through? idk if this is the correct method
@sly matrix Has your question been resolved?
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Could someone please explain this to me?
i don't understand what it's saying
it shouldn't be true though
the function that relates angle to x-coordinate is cos, not sin
maybe it starts at 12 o'clock
still doesn't work
it works if it starts at 6 o'clock
anticlockwise = positive 
I read anti-clockwise and thought ah yes the negative direction
there's not enough information, it's mostly false
think about whether it's correct at ø = 0
hm
"with respect to an angle ø"... they don't specify where the angle is
I suppose they want you to assume it's the angle between the origin-ball vector and the x axis, but it's a bit of a stretch honestly
from starting point x = 0
Presumably the standard position then
but it's still going anti-clockwise
x = 0 is the y axis
yeah
but then it moves to the left
but that would mean negative x
but sine x goes positive first
is that good reasoning?
Not really
it is
If the ball starts at (0,-3) (and ø starts at 0) then 3sin(ø) would describe its x coordinate
yeah
but inverted, no?
No
0,−3, bottom of the circle, 6:00
oh, -3
right
but i doubt that's the case
do you know if you go anti-clockwise from the x axis (on the cartesian plane) to measure angle?
the chance that it's true because it's like "i didn't say it doesn't start there" exists, but it's small enough to ignore
hm
The standard way we think of these things is with a unit circle described by (sin t, cos t), where t starts at 0 and ends at 2pi
At t=0, (sin t, cos t) = (1, 0) so it is on the x axis, to the right
t is the angle here, just like ø in your problem, but your problem never specified what ø represents exactly
Here, animate l in this: https://www.desmos.com/calculator/fuetzowbqe
ah
Well people doing Desmos and not telling me
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okay so im doing heat transfer and i seem to be getting the calculations wrong, asking chat gpt to give me questions to practice and when i do the calculations on my own, they seem to be different from the answers i ask it to give.
Don't use chat gpt for math
No thanks
can i at least show you the question and the answer i got?
really, i just need someone to tell me if im getting these right or not
@hushed seal Has your question been resolved?
You'll have more luck finding such tasks by searching on the internet rather than asking ChatGPT anything other than factual questions.
ahh, okay
thank you
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@nimble gulch Has your question been resolved?
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for the case yRx I do not understand how transitivity plays its role here?
I understand all the rough work
I didn't read the whole thing, but I suspect that suppose you have a singular element and a maximal element of the set of size n
then if the singular element is "bigger" than the maximal element of the size-n set
then you need to show that the singular element is bigger than all of the elements of the size-n set
and you use transitivity to show this
say case yRx, the solution says that suppose z in B, x<z, so y < z, This is to show how if the maximal x is smaller than z then y is also smallet than z because y<x. But z can't be in B if x is maximal
but then if you are already claiming x to be maximal why do you have to say z not in B{x} by maximality at y?
okay yeah this solution kinda makes it a little confusing because it proves it by contradiction
it supposes that there is a z in B that is bigger than x
and then uses transitivity to show that z is bigger than y, which contradicts the maximality of y (because y is alleged to be maximal in B and z is alleged to be in B)
I guess you have to do it this way, because it's a partial order
Ahh okok I dont want to close this channel cause I still wanna continue this question, but I have 2 and a half hours of lecture after
can I just keep this channel
I think it'll autoclose after a while
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I need immediate help please
<@&286206848099549185>
Do you see some similarity between this and series of ln(1-x)
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Hi. I am trying to understand the Möbius inversion formula properly. I've digested the proof of the version, where the arithmetic function f and its summator F are being inverted via the Möbius function mu. However, it is not clear why this proof should hold for the case, when f and F are not arithmetic functions, but just mappings from natural numbers N to any abelian group G.
How can we be multiplying here, if it's an additive abelian group for example?
<@&286206848099549185>
you are multiplying by an integer
which is basically repeated addition
which is fine in an abelian group
Ok, i was just wondering if that's ok, i need to just write down the justification properly. Thank you. More in #advanced-number-theory
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Solve for BD
$AC^2= \frac{BD^2+BD^2 \times Tan(\Theta)^2 \times Tan(\alpha)^2 }{ Tan(\theta)^2 \times Tan(\alpha)^2}$
Mr. Macro
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help please
hello?
!1c
Please stick to your channel.
hm
find the current
then subtract that thing from both the downstream and upstream time
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Hello, I am stuck trying to alter the form of the equation to the general form of linear differential equations of the first order and the first degree
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have you drawn the figure yet?
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is there a quicker way to solve this than partial integration?
yea... write...
ohh you can probably say that the integral from 0 to 2pi of any sin or cos to some uneven power is always 0
$\cos x \cos 2x = \cos(2x-x) - \sin2x \sin x$
jan Niku
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what is the asnwer to this question
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I got D but my friend says A
@versed wolf
Show your work, and if possible, explain where you are stuck.
How did you get D
ok so if z is cis-2pi/3 then the conjugate must be cis2pi/3 so if we square z by 4 then we add cis-2pi/3 4 times to get 2pi/3
How do you represent z ?
rcistheta
I mean z= e^-2pi/3 right?
cis(-4*2pi/3) = cis(-8pi/3) = cis(-8pi/3 + 6pi/3) = cis(-2pi/3)
the modulus in this question is a bit iffy since it should not remain constant
$z* z’= |z|^2$
.doc
.doc
or z’= 1/z
is it B then?
Yes
This just means, the conjugate of your complex number is the multiplicative inverse
👍
This particularly forms a group under complex multiplication
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i'm kinda confused by the leaking and pumping at the same time, help would be appreciated!
it's related rates btw
@low matrix Has your question been resolved?
Are you online rn?
yes!
@low matrix Has your question been resolved?
if ur still here, just use u for the combined pumpage/leakage ignore that part for now
if this hjelps
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you know i got this one sorted, btw
just rewrite $\cos ^3 x + 1 = \cos x (1-\sin ^2 x) + 1$
jan Niku
this leads to a very natural and easy u sub integral as the "hardest part"
$\int \cos x - \int \sin ^2 x \cos x + \int$
jan Niku
clearly only $\int _0 ^{2\pi} \dd x$ is the only one with value over 0 to 2 pi
jan Niku
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Hello. I am having a world of problems trying to understand how to work out part b in this problem. I'm really not seeing the big picture. Any poiinters??
Laplace's equation in two dimensions is the PDE for $u(x, y)$
$$
\frac{\partial^2 u}{\partial x^2}+\frac{\partial^2 u}{\partial y^2}=0 .
$$
Such $u$ are "steady-state" (i.e., time-independent) solutions to the 2-dimensional heat equation. Consider this on $\left[0, L_1\right] \times\left[0, L_2\right]$, with vanishing Neumann boundary conditions on the left, right, and bottom sides:
$$
\frac{\partial u}{\partial x}(0, y)=0=\frac{\partial u}{\partial x}\left(L_1, y\right), \frac{\partial u}{\partial y}(x, 0)=0 .
$$
We'll analyze that boundary value problem (with vanishing Neumann conditions along 3 of the 4 sides).
(a) Show that the nonzero separated BVP solutions $X(x) Y(y)$ are the functions
$$
c_n \cos \left(\left(n \pi / L_1\right) x\right)\left(e^{\left(n \pi / L_1\right) y}+e^{-\left(n \pi / L_1\right) y}\right)
$$
for $n \geq 0$ with scalar $c_n \neq 0$ (don't overlook $n=0$, related to constant solutions to an ODE).
(b) Consider solutions $u(x, y)$ to the BVP subject to the further Dirichlet-style boundary condition $u\left(x, L_2\right)=f(x)$ along the top side, for a given function $f:\left[0, L_1\right] \rightarrow \mathbf{R}$ vanishing at the endpoints. Writing $u(x, y)$ as an infinite series
$$
\sum_{n=0}^{\infty} c_n \cos \left(\left(n \pi / L_1\right) x\right)\left(e^{\left(n \pi / L_1\right) y}+e^{-\left(n \pi / L_1\right) y}\right)
$$
in separated solutions, express the $c_n$ 's in terms of Fourier-type integrals involving $f(x)$.
Hint for (b): the $2 L_1$-periodic series $\sum_{k=0}^{\infty} a_k \cos \left(\left(k \pi / L_1\right) x\right)$ computing the even extension $f_{\text {even }}:\left[-L_1, L_1\right] \rightarrow \mathbf{R}$ of $f(x)$ has coefficients given in Proposition 21.1.8(i) with $L=2 L_1$.
True
@high vortex Has your question been resolved?
Thanks :)
@high vortex Has your question been resolved?
Probably should show the proposition mentioned
@high vortex Has your question been resolved?
sorry, one sec
Proposition 21.1.8. Let $f(x)$ be an $L$-periodic function, and define $\omega=2 \pi / L$.
(i) For even $f(x)$, the associated Fourier series is $a_0+\sum_{k=1}^{\infty} a_k \cos (k w x)$ ("cosine series") with $a_0=\frac{1}{L / 2} \int_0^{L / 2} f(x) d x, \quad a_k=\frac{2}{L / 2} \int_0^{L / 2} f(x) \cos (k \omega x) d x$ for $k \geq 1$.
(ii) For odd $f(x)$, the associated Fourier series is $\sum_{k=1}^{\infty} b_k \sin (k \omega x)$ ("sine series") with
$$
b_k=\frac{2}{L / 2} \int_0^{L / 2} f(x) \sin (k \omega x) d x \text { for } k \geq 1 \text {. }
$$
True
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can a linearly dependent set of vectors be orthogonal?
Perhaps if there are two vectors and one of them is the zero vector
Can't see any other possibility
Or if it's just {0}
@pale drift Has your question been resolved?
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How would I go about solving this?
angle addition formula for cosine
^
are you curious how I knew that
(eventually)
because the angle addition identies follow a pattern
for cosine, it's cos(A +/- B) = cos(A)cos(B) -/+ sin(A)sin(B)
for sine, it's sin(A +/- B) = sin(A)cos(B) +/- cos(B)sin(A)
hmm
What about the product to sum identities?
Could that be used in this scenario?
I don't know, but the angle addition/subtraction identities are more well-known
you should use the angle addition formula for cosine.
get 1 by itself on RHS, factor out the 2 on the LHS.
okay I am trying it out
So
2cos(-3x)cos(2x) = 1 + 2sin(-2x)sin(2x) can be translated as cos(-3x +/- 2x) = cos(-3x)cos(2x) +/- sin(-3x)sin(2x)?
@limber quartz
thats for the LHS
no
you messed it up or typed it wrong not quite: you kept my notation for the signs when you should just stick to what you were given
rearrange what you were given.
get the 1 by itself.
on the left hand side, factor out the 2.
oh
then divide both sides by 2
the left hand side will be in the same form as the angle addition formula for cosine.
translate that
oh I see
you are kind of right
but
pick which sign you have
you have subtraction on the right, which is associated with addition on the left (that's why it's the angle ADDITION formula for cosine)
don't worry about my formulas
:
yet
page 2 under "Sum and Difference Formulas"
https://tutorial.math.lamar.edu/pdf/trig_cheat_sheet.pdf
2cos(-3x)cos(2x) = 1 + 2sin(-2x)sin(2x) can be translated as cos(-3x)cos(2x) - sin(-3x)sin(2x) = 1/2?
yes finally
then
Thank god
I finally see it
Imma solve it then send the answer (if you have time to review it)
did you translate it yet?
use the formula sheet
yessir
$$\cos{(A \pm B)} = \cos{(A)}\cos{(B)} \mp \sin{(A)}\sin{(B)}$$
Disorganized
good
What happens to the 1/2?
tell me.
it's happening right now
!
😛
transitive property
"if x = y and y = z, then x = z"
yeah
what else do we know about the cosine function that will simplify that even more
"cosine is an (blank) function"
what does this mean:
f(-x) = f(x)
odd
no
odd is
f(-x) = -f(x)
the "-" has to equal "+" for it to be even
which cosine has
hmm
phrasing is a little imprecise
rather
cosine is an even function because you can fold the graph over the y-axis onto itself.
algebraically (or graphically, if you plot it), for any input x, cos(-x) = cos(x)
so the final answer (without finding the solutions in the interval) is cos(x)?
no
that's not the final answer
this is the next logical step
use the fact that cosine is an even function with transitive property again
x = (2k + 1) pi/2?
"cos(-x) = 1/2
and cos(-x) = cos(x)
therefore,
cos(x) = 1/2"
oh
wouldn't be that
because when k=0, x = pi/2, which isn't going to work
use what I just wrote
(typed)
the last line
to draw a right triangle with angle x
doing it now
or, you know
you don't need to draw the picture if you have the unit circle memorized
what angle theta (in our case, x) has a cosine value of 1/2?
so pi/3 and 5pi/3
thank you
would
or rather
is x already in the interval [0,2pi) ?
Or would I need to solve that as well?
wait a min
you found the most accute angle that had that trig ratio
or as we would say, the reference angle/triangle
So there are only two solutions within the interval [0,2pi)?
As those are the only ones we found.
I wish I could draw you the picture
you would draw the reference triangle in Q1
and that angle in Q1 would have its terminal side as the hypotenuse
I hope that is obvious
but then, since cosine is also positive in Q2 (positive is desired because since we had cos(x) = +1/2)
ah
we lay the same reference triangle in Q2 on the -x axis
and the new angle terminates at that hypotenuse
but notice that would just be 180 degrees - x
or pi - x
that is,
pi/3, pi - pi/3 = 2pi/3
oh
you got the other angle wrong
I think
oh cheese and crackers
I got it wrong
I'm thinking of sine again!
lol
don't orient the second triangle along the -x axis
flip it OVER the +x axis
then the angle you desire is 2pi - pi/3
6pi/3 - pi/3 = 5pi/3
so you are correct
yes
sorry
nah
Q2 being the +x axis?
flip it into Q4
because cosine has positve values in Q1 and Q4
and that is because the horizontal components of the right triangles are positive in Q1 and Q4
yep
WHAT AM I THINKING Q2
I meant Q4
yes
got it
Thank you very much for your assitance and help!
This is a very through conversation.
hang on
oh dear there's more?
ah
in the unit circle
the hypotenues is always "1 unit"
any triangle can have all its sides scaled up or down by the same amount to make this so.
got it
it's only the x and y-components of the triangle that have a sign (positive or negative). The hypotenuse is always positive.
so the rules for flipping the reference triangles can be visualized picorally by just noticing where the sine and cosine values are the same result for congruent triangles in different quadrants
the signs of the sides are different in different quadrants, obviously
you're welcome
hmmm
I added the quadrant labels and the signs of cos, sin, tan (in that order) for each quadrant
Thank you very much!
no problem
I wish you a great rest of your night or day (wherever you are in the world).
Cheers!
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anyone?
Calculate the length of segment AD, if |OA| = 50 cm, |OB| = 28 cm, and [OCI] = 7 cm.
into english ^^
just use the intercept theorem
@timid silo Has your question been resolved?
wow you know a lot of things
“• W troikacie ABC o bokach drugosci: | AB| = 18 cm, | BC| = 24 cm, | AC| = 20 cm poprowadzono dwusieczna kata ABC, która preciela bok AC w punkcie D. Oblicz dugosci odcinkow AD i CD.”
Strasznie nie kumam o co tu chodzi
oznacz sobie szukane boki jako x i y
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smiling
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??
jestem , potem piszesz x / y = x / (20-x) = 18/24 = 3/4
obliczasz 4x = 3(20-x) <=> 7x = 60 itd
x = 60/7 , y = 80/7,
@timid silo Has your question been resolved?
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hi
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why is my answer in negatives? it should be 10/9
the question is $$\int^1_0 \frac{3x}{\sqrt{4-3x}}$$
JustToPro