#help-23
1 messages · Page 432 of 1
sin 26 and cos 26?
other way round
no diff
Close what?
hi mercury
np, btw only the original poster and helpful can close posts
Hi Moey!
Mods too.
what am i supposed to do here
Eh, check ASTC rule.
whats that
isnt what i expected
It is ASTC rule not Acts
uhh i dont get this for example when cos is negative in s it syas its negative in A it says its positive
Please clarify
ASTC NOT ACTS
It stands for All, Sin, Tangent, Cosine
ok but why is it when cos is negative the answer is both positive and negative
The answer of what
look at what i circled
I think that trigonometry works that way . Sometimes Cos is negative and sometimes positive. Its value is positive or negative
then why is there a rule that states the obvious
To allow us to remember
Ehh... why?
It is like metaphor helps us remember stuff
i dont get the rule
The rule states that all trigonometric functions are positive in 1st quadrant
ohhhhh
Which means the adjacent and hypotenuse are positive.
now i get the rule
Every point on the circle is cosx, sinx
i get it
That's why they say , a picture is worth a thousand words
whose they
Everyone mean to say not specifically
Its (cosx, sinx) . That's the form of each piece on circle in coordinate plane
It obvious
As hypotenuse is 1
Eh... ?
What its true
Sounds confusing.
At x= 0 the point is 1,0 as radius is 1
And at x= π/2 point is 0,1
Find a single counter example if possible
Counter example for?
@median sand idk im stupid
Minus 2pi.
You rotate it anticlockwise and still give the same coordinate.
It is like a clock.
If it points at 4, you rotate the clock 12 more hours, still give you number 4.
The other way round, I'd say
Yea it is.
But you'd get the same result
Ehh still the same.
(luckily cos is even)
Cos(-40)=cos(40).
i dont get the reason tho
But for cos only.
Read this please Moey.
Thanks to the concept of PERIODICITY
Lucky him 
ohh so it loops
It does.
Yeah that's the same concept
does it work with tan?
yes
Yeah apply same concept.
thanks
Well also note that tan also the same value if quadrants are opposite diagonally.
Such that tan x = tan pi+x.
There is.
Check this.
so i have to times it by pi?
Plus.
ok
how should i put it in a calc
cause i did tan(15)+pi it gave me me decimals
First, identify which pairs are in opposite quadrants that are diagonal.
Tan (15+180)
If you use pi, then change 15 to radiants lol.
b-c,d,e and a-c,d,e
Great.
Now check if any angle in first quadrant satisfies the other = 180 + itself?
A.k.a. If you have an angle x in quadrant 1, is other angle = 180 +x?
Which in third quadrant.
It is just an example, now try tan 15 if it is the same.
that was simple
I know right.
how do i do b
What was question (a)?
What do you notice about, let's say, sin100° and sin80° ?
How are the two values? Are they equal or different?
they are the same
Awesome, and how are 100° and 80° related to each other?
They sum up to which angle?
Good
hi again
you need help with this?
Nah.
yes
||ofc not im doing this for fun, however lets not talk abt that too much cuz i dont wanna derail this||
C or d?
c
which answer do you need to justify
Yeah appeal to the fact that which quadrant sin and cos positive.
he needs to prove the quadrants in which sinx and cosx are positive?
sin(180-theta)=sin theta
ah okay
so idk how
i have the answer and solution but im not looking at it till we solve
when u get back ping me
wassup
opp/hyp
on a unit circle how would u visualise it
its the y axis
cos is the x axis
a full loop or half
no just half
yep
yes
so thats enough right
i would say it is
thats the book answer
mhm
from how i understand it we did the same thing in basically a more laypersons way
@spark leaf Has your question been resolved?
@ who ever is left
180-137?
Yeah
ohh ok very simple
Yep
What you mean by deduct large numbers?
Subtract?
Or maybe they meant deduce the sine of large numbers
Which question ?
c
C?
yep
Well we see that the angle for Q is -theta, so can you think about what it's coordinates would be
-theta, cos
i think u guys had enough
ill sleep and do this tmrw
its 1.30am
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hello can someone give me an idea for the last question pls
You basically wanna do an integral, but you need to get the bounds right
You know how integrals work right
(look at the rest of the test)
Well then this should be pretty simple
well an idea: is to write the integral of the curve from 0 to k to get the area as a function of k, and try to find the k such that that area is half of the total
(you will therefore also need to calculate the total area, and you'll get basically an equation to solve for k)
yeah
that way your result will be some function of k for that area
does that idea make sense to you? do you see where i am going with it?
because that's the important part, not just get the answer you know, but learn how to get there
ok, and now that you have that, you must make it so that this is equal to half the total area for some k
so you can say this = total area/2, and that gives you an equation that you can solve and get your k
u mean solve m this to get K right
who is m?
oh oops, yeah
why = 0?
cuz I don’t know that is itb= to
I have to solve for k right
Ohh hahhaa
I see eit
yeah, but it is not = 0, think about what you just have, the 100ln((k+5)/5) what does that represent?
your equation is still wrong
Ohhh
Ohhhh
what you have is the red area
and you want this to be half of the whole thing
does that make sense?
Yesss
cool
So then I will let this euqla to the half of the total area I have before
well you need to calculate the total area, and then make what you have equal to half of that
you havent yet calculated the total area normally
oh i will calculate the total area by integrate y from 0 to 40?
yeah exactly
exactly yes
it may be helpful to have a drawing
hehehehe yahhh:)))
i find its very often useful to do drawings to not forget what you are doing and where you are going
just like this, its enough
this basically sums up your whole problem
woww true true
oh yeah, but normally for this type of question
is it non cas or cas active?
what does that mean 😅 im french so there is some vocabulary i dont have
this should be doable without a calculator
try to write your equation that you get down
oh no i’m cooked
dont worry, once you have written it you will see its not that bad
yeahh hehehe
are u doing vce math right now?
what is vce?
no because i am french, we dont have that i think
ohhhh
wait what year are u currently in
im 20, im studying engineering rn, im down with school
i find it interesting yeah xD
:))) woww xd
can u help me for one more pls
:))) i set it equal to 0
but the cas is broken
what equal to zero?
we need to finish your first problem
the differentiate of h(x)
no?
ohh yes
did you have an answer?
i didnt understand your reasoning
it will be the reflect
it would be on the left of the y axis, that wouldnt be too logical now would it?
we want to divide the area in half and you have your k outside of the area, that would be pretty weird
better, it should be between 0 and 40
or else it makes no sense even
yess so only k=10 make sense
yup and that is the answer indeed :)
now for your other problem, i am going to sleep because it is 1:40 am for me, but you can create a new channel and ask someone else for help
it kinda is yes where i am
good night good night thank youuu
my pleasure :) nice work from you too
cya
(dont forget to close this if you create new help channel)
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hey guys i’ve been staring at this projectile motion problem for a while and it’s driving me crazy i’m trying to derive the general formula for the maximum horizontal range r but here’s the catch the projectile is launched from a cliff of height h not from the ground can someone walk me through the math i’m specifically looking for the breakdown using quadratic solutions and how trigonometric identities come into play here i really want to understand how the starting height h changes the optimal angle compared to the usual 45 degrees we learn in class down for a step by step challenge if anyone is free to help thanks a ton
I don't see why this couldn't be handled here it's a beyond common trope for math problems
What would be nice is some more specificity to the question being asked
Show us the picture of your question?
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
@minor ember Has your question been resolved?
There’s no textbook photo, I actually came up with this myself. I'm self-studying and wanted to challenge myself by deriving the general formula for a launch from height h instead of the ground. I’m really stuck on the quadratic breakdown and the trig part. I made the diagram to show exactly what I'm trying to derive. Any help with the steps would be huge!
Then a graph or something would be great!
@minor ember Has your question been resolved?
Well, what have you done already?
I mean, you can just first define v0, angle theta, h, and g though. And perhaps make some vertical and horizontal components for initial velocity.
Thanks for the tips! I’m currently calculating the components. So v_{0x} would be v_0 \cos(\theta) and v_{0y} is v_0 \sin(\theta), right? I'll let you know what I get for the final range
I’m working on the time of flight now. Since it’s launched from a height h, should I use the quadratic formula for -h = v_{0y}t - 0.5gt^2? It looks a bit tricky
why -h
@minor ember Has your question been resolved?
Because the displacement is technically negative, considering the body is moving down
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can anyone explain to me for the question a)ii)
if i recall the number of arrangements in a circle is (n-1)! so if were separating the vowels and what not. so in the first 12 letters we have {a, b, c, d, e, f, g, h, i, j, k, l} and from that set we have the vowels being {a, e, i}
provided i have understood the question correctly
theres 7 consonants and 5 vowels
ah k (didnt know the 12 letters they were referencing)
so instead we got something like this {V, C, V, C, V, C ...}
yea
where V and C are vowels and consonants respectively
and we know that #C > #V
so we can also have arrangements such as {C, C, V, C, V, C, ...}
yes
hm ok
well, the maximum # of ways they can be arranged is 11!
but thats provided that {V, V} is a legal input
there will be permutation
yea
its not 11
they are in a circle no?
they are arranged in a circle, so the maximum # of ways they can be arranged (without any extra rules) is (n-1)! so, (12-1)! or 11!
then we work down from that number
so we can do this process for the 7 consonants and 5 vowels
so, for C we get (7-1)! or 6! = 720. And to make sure no two Vowels can touch they need to be placed between each consonant. so we get get 7C5 for this arrangement, and then how many ways can our Vowels be arranged in general? 5!
do you think you can go from here?
-# and as predicted, our value is significantly less than 11! since thats the maximum ways in general
so, you should get 6! * 7C5 * 5! yea. Do you know how to turn this into a more simplified version which includes a permutation?
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Can someone check this please?
But when u diff log_e(1/y) u get 1/(1/y) = y?
why is there a Negative too btw
1/(1/y) d/dx(1/y)
y* -1/y^2 * dy/dx
-1/y * dy/dx
is there something wrong?
is that ln (1/y) in numerator??
where
there wont be negative in the first term of numerator
and the denominator is kinda wrong from mine
hold on
(apologies for butting in muffin et al), the second line when you apply the chain rule to the second term
$x^3 \log_e(\frac{1}{y})$
$3x^2 \log_e(y^{-1})$ is correct but on $\log_e(y^{-1})$ you forgot to take the derivative of the innermost function, i.e. $1/y$
so when you take $\frac{d}{dx} \left( \log_e(y^{-1}) \right) = \frac{1}{y^{-1}} \cdot \frac{d}{dy}(y^{-1}) \cdot \frac{dy}{dx}$ this should be $= y \cdot (-y^{-2}) \frac{dy}{dx}$ by applying the chain rule
reze ♡
reze ♡
yea keep it minimalistic
yess sir
@proven smelt Has your question been resolved?
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Hi, i need help with the task below. I have already done (a), and i got R = 7 for the first sphere, and R = 10 for the second one. For b, do i need to find some kind of plane in order to solve the problem? I marked the circle of intersection on the picture below, but i am not sure if thats correct.
**The task:
**A sphere is given by its equation x^2+y^2+z^2-2x+6y-6z-30=0. Another sphere is given by its equation x^2+y^2+z^2-10x-18y+6=0.
(a): Find the radius of the spheres.
**(b): **The intersection curve between the two sphere surfaces is a circle. Find the radius and the center of the circle of intersection.
You can equate the two expressions
Think.
I don know, the plane?
Unfortunately not necessarily, because you're still gonna have 3 variables in there.
Yeah, if you equate the non-zero sides, you're gonna get the plane in which the circle lies
It's the same approach like last time, you'd set up a line that goes through the centers respectively and find the normal vector of the plane
Oh okai
But first i need to find the plane
And theen the line
When i know the normal vector
What if we do (x^2+y^2+z^2-2x+6y-6z-30)^2 + (x^2+y^2+z^2-10x-18y+6)^2 = 0?
Right?
Just equate the spheres as already mentioned
-# this'd not be very helpful, you'd get some sphere which contains the circle, but it'd be difficult to extract the circle from it
Okei
8x + 24y -6z -36 = 0
And soo the normal vector would be (8, 24, -6)
Okai got it
Thank youuu
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i got a question to derviatives so ik that ln(e^x) = x but why is log(10^x) = x or 10^log(x)=x i dont understand
that's the definition of a logarithm
the logarithm undos an exponential function with the same base
ln is the logarithm of base e, log is usually representative of the logarithm of base 10
The base of the log in log(10^x) = x must be 10 for it to be true.
in any case, where does this involve derivatives if i may ask?
idk im new to maths writing an exam tmrw
makes sense
would that be all?
Derivative?
No it's because of how e is defined
Tho the proof would depend on which definition you're using
but isnt that the special thing abt the constant e the function valueu equals the gradient
or am i understanding it wrong
yea, id say so
sure, yes
because [
\dv x(a^x) = a^x \2\ln(a)
]
although i feel like that's more of a consequence of change of base rather than directly from derivatives
though that is more to do with how the number e is constructed
i.e., this becomes a tautological truth that the gradient of e^x is proportional to e^x itself
Though do note e^x isn't the only function with that property, any function of the form k×e^x for real values of k also satisfy that fact
thats what i wanted to ask
so in the exam theres prob an question with like N(t)= initial valueu times e^kt
buut what is even k expressing
the growth rate
relative growth rate
so k>0 is growth
it is analogous to the differential equation [
\dv[N]t = k\2N
]
Organic math? 😢
The growth (the derivative) is proportional to its current size (N)
pardon?
so negative numbers is decay or what
yep
and fractions?
Decay is smth wen any organic substance rots or smth-
if it is positive, the converse
oh, not talking about that here
Alr
fractions only imply that the growth/decay rate is relatively slow
ah
for illustration sake
im presuming youre asking whether or not the graph will ever approach y = 1, that is not necessarily the case, and only is true iff you have e^kt + 1
that is, the graph has an asymptote at y = 1
wait im confused i might be not interpreting what youre saying correctly
they are saying the y-intercept is y = 1 because e^0 = 1
ah
and it doesnt matter what value k has because for exapmle e^2 times 0 is still e^0
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how to continue further?
I'm prolly wrong on this but you can consider
subtract [x] and {x} to both sides and add 1 and factor LHS ||to ([x]-1)({x}-1)=1||
since {x} is fractional, you can make assumptions such as: ||it must be less than 1 so {x}-1 is less than 0 or negative, since the RHS is positive, [x]-1 must be less than 0 and [x] must also be less than 1||
now we have numbers ||0 to -inf|| to consider, although I'm not entirely sure on that last part
-# I sold 🥀
is 0 not a solution
wouldn't 4 also give
0
since it's 4+0/whatever
this is weird
how did they get here?
were there some other conditions in the problem?
i think this book is cooked
are you sure you are reading the correct pages
page 1 starts well, but page 2 talks about unrelated stuff
mb it was my mistake
im cooked
oh lol
this looks better
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Okay, so I think I get the 5 km/h part, and I get the 35 km/h part, but after that, it gets a little shaky. How should I set up this problem?
you pretty much have it, you're just missing the northward 7km/h component of the current
then use pythagoras
just plus the coordinates
you can add them in any order
Does that include the (0, 7) coordinate or is it just the (0, 35) + (12, 0) ones?
plus them all
since 7km and 35km are in same direction, so let it be y and 12km is x positive
so (12,42)
let north be y and east be x
Got that part right. Now I assume I have to do the Pythagorean Theorem on those values.
yes
So 12^2 + 42^2 = c^2.
isnt it (7, 42) cuz theres 5 km/h on the west asw
you are forgetting something
ariah is walking 5km in west direction, which is opposite to east
so you gotta minus that
oh mb i thought u missed that 😭
So that's (2, 42).
I got 1768 after the Pythagorean Theorem.
Oh wait, that's wrong.
(12,42) + (-5,0)
It's actually (7, 42).
yes
Rounded to the nearest tenth, that's 42.6.
yes
Got it! Thank you so much!
a+b whole square?
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How many more equations to finish this
That looks really sick so far bro
@static harness Has your question been resolved?
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How did they multiple this? I don’t see it
$\frac{4}{12} = \frac{1}{3}$
riemann
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hello can someone help me w this
first i would plug into the average value thing
y-y1/x-x1
lol that seems to be something for linear functions maybe
probably you want to use an integral?
in calculus you should learn a general form to find the average value of any function over any interval
oh so integral of Ia-x)^2 right
yea you intergrate over the interval
and divide by the length
so integral from -1 to 1 of (a-x)^2
and the interval has length 2 so u divide at the end
i would expand (a-x)^2 but it doesn't really matter
you should pick up a minus sign when you integrate, because of the -x
yea its good except for the minus sign from chain rule
(or just change it to (x-a)^2)
yea
but after i done it
all you do is expand and solve
should be easy
i think the cubic terms cancel as well so its just a quadratic equation
3/2 or -3/2
ye
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I don't think that top part, (1+cos(2x+pi))/2 is equal to cos^2(2x+pi)
cos^2(x)=(1+cos2x)/2 not (1+cosx)/2
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hello
can soemone help me w this pls
which part, and where are you stuck?
the part b
are you sure about your answer for (a)? this looks questionable
shouldn't it just be 20
not 21.whateverthatis
anyway, for part (b), yes you want to calculate h'(x) and set it equal to zero
but where did the pi's come from?
the derivative of sin(x/20) should just be (1/20)cos(x/20)
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How can I prove this?
What I currently have:
Is f continuous?
It doesn't say
Let's suppose that $\lim_{x\to \infty} f(x)=L.$ That means that $\forall \varepsilon>0, \exists N>0 \text{such that if } x>N \Rightarrow |f(x)-L|<\varepsilon. $ Now take $\delta=\frac{1}{N}$, then and let $t=\frac{1}{x}$. Then if $0<t<\delta \Rightarrow \frac{1}{t}>\frac{1}{\delta} \Rightarrow |f(\frac{1}{t})-L|<\varepsilon$
YuyuHenry
YuyuHenry
I asked chatgpt to translate what I had in an image
Like, is this correct?
<@&286206848099549185>

what do you think?
it is correct
did you not come up with it
maybe that's why
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probably the easiest way is to use the identity for 1-cosx but if you don’t know it then might not be obvious
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✅ Original question: #help-23 message
I’m finding my bounds are both 1, but this doesn’t make sense?
oh yea see in periodic functions
such as in cos and sin
the graph goes up x axis and below and up and below and so on
something went wrong here
the integrand on the first line is nonnegative, but on the third line is is not
probably a sqrt(x^2) = x type of blunder
so if u find area (integration) or bounds on the given limits then basically u will be cancelling everything and will make it zero
And also the angle should be θ/2 @proven smelt
^
Because you used double angle formula
$(1 - \cos \theta)^{3/2} = \left( 2\sin^2\left(\frac{\theta}{2}\right) \right)^{3/2}$ is what it should look like if i’m not mistaken
wait
yeah
wait why’d id post the first part
u have to break the limits
from 0 to pie and from pie to 2pie
or just 2 times 0 to pie
in order to not get same bounds
$\left( 2\sin^2\left(\frac{\theta}{2}\right) \right)^{3/2}$
Yatto
yeah this
OP hasn't replied since the initial post, maybe let's not do the problem for him while he snoozes 😁
You snooze you lose
facts are stubborn things
ohh. this helps.
hm lemme try again
well if we’re showing him what he SHOULD be getting then maybe it can help him see how to get said answer 😴
@proven smelt Has your question been resolved?
I got it, thanks guys!!
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Is my understanding correct?
Cause the cube is symmetrical b CB has the same magnitude of b, but goes the opposite direction, thus -b
So doing this CF = (-b) + c
looks fine
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how to construct it in geogebra?
have done this so far
i know that D lies on this circle
which has AC as diameter
Hint: there's a pair of similar triangles
-# sorry to intterupt jus thought this might be helpfull
-# for refrence angle B here is always 90 degrees!
i think i see now
since BC and AB intersect in an angle of 90 we can rotate the square in 90 degrees and then BC gonna be parallel to AB
and then CBH gonna be equal to BAG
but how can i use this to construct tho
A solution that you could try is related to this. You know the lengths of BC,BA and CA. Also, AD is the side length of the square. All these points lie on a circle
can we not use vectors and coordinate geometry to do this?
A hint for you to try is to treat AD as a chord and find the length of it
i know how to solve it, i just want to construct it perfectly from here
using synthetic methods
this is an approximation btw
lets say we have this, where AB is 4 and BC is 3
how can we have ABC inscribed in a square, construct this square
@gilded star Has your question been resolved?
maybe if we start like this
A (origin) will be the common vertex of the square and the triangle
we're basically trying to circumscribe a square now
so we draw the 2 semicircles - the 2 neighboring corners of the square must lie on those
and they must form 90° angle with A
so let's rotate one of the semicircles 90°
and where they intersect (the rotated with non-rotated), there is our corner
since you know what the triangle is, your problem is basically just circumscribing a square s.t. they share one vertex
so the solution works generally for any non-obtuse triangle
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hi I need help
@lavish ermine Has your question been resolved?
(In the future, please make the first message you send the actual question since that's what the bot pins. This saves us the effort of having to change the pin manually.)
I'd advise you to not write so small
seems like you changed from 0.65 to 0.62 mid-calculation?
nah its 0.65 that's my handwriting sorry

I mean
$$v_n=200 \cdot 0.65^{n+1}+50 \cdot \frac{0.65^{n+1}-1}{0.65-1}$$
should be fine. Though you can simplify it tbf.
Civil Service Pigeon
,w 200+50(\frac{1}{\frac{13}{20}-1})
$$v_n=200 \cdot 0.65^{n}+50 \cdot \frac{0.65^{n}-1}{0.65-1}$$
Civil Service Pigeon
as in this?
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Determine the coordinates of the intersection points between the asymptotes of the hyperbola and the circle passing by the focus points of the hyperbola
not sure how to start
use the 2 points to make the hyperbola equation prolly
then make the circle equation and solve using algebra
that would be a rough sketch
@mortal marten Has your question been resolved?
yeah (-42)^2/21^2 - (-20sqrt3)/b^2 = 1
b = 20
x^2/21^2 - y^2/20^2 = 1
is rthe equation ofthe hyperbola
and the focus points so c^2 = a^2 + b^2
c^2 = 21^2 + 20^2 c^2 = sqrt841
c = -29 and 29
which means the circles radius is 29
x^2 + y^2 = 29^2 is the circles equation
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I understand that I have to do 6cos(160) + 6sin(160) and stuff like that, but how do I put them together to find the length and angle of both of them combined?
just break into x and y components then add
What you have isn't $\vec{v} = 6\cos(160) + 6\sin(160)$, but rather $\vec{v} = (6\cos(160), 6\sin(160))$. When you add two vectors, you add them coordinate-wise.
Azyrashacorki
So if you have v = (a,b) and w = (c,d), then v+w = (a+c, b+d).
Wow, that sounds much simpler than I was expecting.
So now I just have to add them up.
And do the Pythagorean Theorem.
yes pythag is the length
Okay, I got 4.6 for the first one.
Exactly yes. Then for the angle the best thing to do is to make a quick sketch of which quadrant the resulting vector is in. From the sidelengths you can use trig to get an angle, and you can adjust it according to the quadrant you're in.
Well, they're both negative, so that would be in Quadrant III.
Then, after that, I think I have to get the tangent, because I already have opposite and adjacent (the -4.27 and the -1.71).
I got 201.8 after adding 180 to the arctan.
I'll try submitting that.
Oh wow! That was pretty simple.
Thank you so much!
I'll close this.
.close
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Is 16.95 not get rounded to 16.9 when rounded to the nearest tenth?
It does not
Why?
If the next digit is 5 or above it rounds up
In the hundredths digits?
Yes
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Please @ me I just need someone to explain question 4
Which part?
I just dont know what im supposed to do except find tan, how tho
I dont get the example thats why im here
Which is in between π/2<Q<π
Or u can say Q belongs to 90<Q<180
In 2nd quadrant
I have to find the exact angle
Oof-
Yk wat sin Q is?
What is it
Ohh the formula for din yes
And wats tan?
Sin over cos
Ihh wait ik now sorry
Im wasting ur time
I gtg im at school and break is over
Thanks
Cya
Np
Should I close
Sure
.close
Closed by @spark leaf
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Please @ me question 4
If there is a helper helping please dont interrupt unless they make a mistake, thanks
Which part are you stuck on?
Idk how to do it
Should we start with a?
Actually nvm
Kk
Do we find cos then do sin over cos?
Thats an option yes
Is that the easier way
Im not gonna use it as i didn't learn it yet
Is it possible to find tan with no calc?
Yep
So use that to get cos
Then sin divide by cos
Some calculation is required
Yes
I can find sin and cos with out a calculator so why cant I find tan
Oh I thought you meant calculation
No you dont need a calculator
Let me know when you find tan for the first question
I think you can solve the rest too
Did you solve it @spark leaf ?
you know tan is sin/cos
Yes
Im doing the question rn
Damn i forgot about that
then just follow ASTC rule -> Tan < 0
Given information for sin and cos there are just redundant
What did I do wrong
Ehhh that way is bad
You got the sign wrong thats all
Cos sign?
A better way is that sin theta = 1/3, then theta = sin^-1(1/3), then put -cos(theta)
Since cos was negative and sin was positive, what willthe sign if tan be?
I dont think op has learnt inverse trig
U wrote positive sqrt2/4 for tan
No i didn't
?