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anonymous
 5 years ago
Use an addition or subtraction formula to find the exact value of the expression.
sin(285)
anonymous
 5 years ago
Use an addition or subtraction formula to find the exact value of the expression. sin(285)

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well, lets assume you know the 'obvious' values of sin  {0, 30, 45, 60, 90} + 360n. How can you use them to make 285?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Indeed. Use sin(a+b) with a couple of them and you should be able to work it out. I guess the main problem is how to do it most efficiently.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0That's where i'm cofused

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Something to consider is that sin (180  x) = sin x (the best way is probably to add 2 values of sin between 100 and 180

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0¬_¬ Sin 150 = Sin 30 Sin 135 = Sin 45

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Do you not get why that is true?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Or do you not get that sin(150 + 135) = sin 285

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well, if 0 < x < 180 , then sin (180  x) = sin x Hence the above claim. And 135 + 150 = 285 (clearly) sin(150 + 135) = sin(150)cos(135) + sin(135)cos(150) = sin(30)cos(135) + sin(45)(cos(150) All you need to do is use a SIMILAR rule one the cos values and you're done. I'll leave that to you. NB this is how I'd do it, but there may be a quicker way.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Gah, actually I prefer: Sin 285 = sin (285  360) = sin(75) Sin is an odd function => sin(75) = sin(75) sin 75 = sin(30+45) = blah. sin 35 = blah.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Last line is sin(75). Where did you get 90 from?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i have no idea what sin 35= ?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0It's meant to be sin(75) , sorry! But sin (75) = sin(45 + 30) = sin(45)cos(30) + sin(30)cos(45) And sin(285) = sin(75) = sin(75) = (sin(45)cos(30) + sin(30)cos(45)) Because sin(a) = sin(a)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hmm, INew, wouldn't it be easier if you just drew the graph and compute it from the graph? :) it'll be alot easier ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sin(45) = cos(45) = 1/sqrt(2) sin(30) = 1/2 cos(30) = sqrt(3)/2 \[\implies \sin(75) = \frac{1}{\sqrt{2}} \cdot \left(\frac{1}{2} + \frac{\sqrt{3}}{2}\right) = \frac{1+ \sqrt{3}}{2\sqrt{2}} = \frac{\sqrt{2} + \sqrt{6}}{4} = \sin(285)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Easy to compute \[\frac{\sqrt{6} + \sqrt{2}}{4}\] from a graph? You must be pretty badass with graphs.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol, yes by drawing the graph. You know turning the lines in circles we have 90 180 360 270 he'll easily figure out angle by then :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Just admit you were wrong, please, and I won't have to own you.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the graph is actually easier, never realized it :p

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0LOL, do you know how yo use it loco :)?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The question specifically asks to use the addition formulae, and besides, no 'circle' will give you the angle 285.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol, yes it will :) , you've never used it right?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0kind of, ta showed it to us. still iffy on it but practicing.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0besides loco, the information INew has given you also is valuable, work with both ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0but did you figure it out ? :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sstarica, please, draw me a circle which can give the exact value I calculated without, in essence, just using the addition formulae in diagram form.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I can't draw it here, but you can twirl the line till you get the given angle, then you can figure out which angles to add. Those angles will be easy to compute since they're small, and in the end you can just add them up to find the sin of them ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oh, adding angles? Weird, just what I did. BTW drawing is harder than saying 285 = 360  75 => we need sin(75)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Simplify the trigonometric expression. cos[x]/sec[x] + sin[x]/csc[x]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sorry, I thought they were implying they could do the hard part in a circle, not the easy part :/

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I'm not fighting LOL, we're discussing loco ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.01/sec = cos. 1/csc = sin. cos * 1/sec = .... etc

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0how about we i mean u guys solve this problem

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you still didn't solve it? ..

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0no, i hate this stuff

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0don't say that, you still didn't master it , but you will with practice and it'll be easy on you ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i've been practicing a lot, but still having trouble :'(

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\frac{\cos x}{\sec x} = \frac{\cos x}{\frac{1}{\cos x}} = \cos^2x\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0it's alright, keep on practicing and you'll master it :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0What's wrong? (Before answering, note that I am never wrong)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sorry, i thought that was the answer

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0we all make mistakes Inew :) even I, even the most intelligent, but noone said you're wrong, but your way is complicated.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0try to explain it in a simple way :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I was doing one half of it. See if you can apply the same logic to the next part  you might find it simlpifies to.. something nice.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0He meant I am wrong about the second problem he posted in here. I only did half of it

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yes, my FIRST method was comlpicated, but my second was amazing.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0he posted another question?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol, good that you've made it easier ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Thankfully still no graphs required

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh that one , LOL LOCO! you've posted it in a different thread =D and I was writing it down

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0nvm it, INew answered it though :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0it's not right though

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Alright we have :\[\cos(x)/\sec(x) + \sin(x)/\csc(x)\] sec x = 1/cosx and csc x = 1/sin x so: \[[\cos(x)/1/\cos(x)] + [\sin(x)/1/\sin(x)]\] simplify and you'll get : \[= \cos^2(x) +\sin^2(x)\] \[= 1\] Correct me if I'm wrong please ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you are right :) i got the same answer

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0No, you aren't wrong. Unless you count not using \frac{}{} for fractions as wrong (I personally do)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol, I didn't get you INew

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\frac{1}{2} \geq 1/2\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hmm, I can't find the frac() symbol lol >_<

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0still don't know how to make that fraction line ^_^"

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0last problem.... Simplify the trigonometric expression. cos[x]/ tan[x] + sex[x]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0frac{a}{b} gives\[\frac{a}{b}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sex(x)  lolololololol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0wish math was that fun

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I general, always write tan as sin/cos , sec as 1/cos etc.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0When trying to simplify things.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0It's alright, we have : \[=\cos^2(x)/sinx + 1/sinx\] \[= [\cos^2x + 1]/\sin(x)\] \[= \sin^2x/sinx = \sin(x)\] ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0maybe? :) correct me lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\cos^2x + 1 \not= \sin^2x\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hmm, where is my mistake

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0For what it's worth, I don't think it simplifies much nicer than how it starts, so is a bad question.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0man, u guys are at it.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0LOL, loco we're not fighting =P, hold on :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ugh, it doesn't simplify.. at all. But also sec x = 1/cos(x) ... >_> sorry

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\sec x + \csc x \sin x\] .. but I'm tired.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Loco left is for a new thread. Un coooooooooooool

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i posted it in a new thread also, but u guys were to busy

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Joke, I know it was. Just unsure what the 'expected' form is.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[=\frac{\cos^2x}{\sin(x)} + 1/cos(x)\]\[= \frac{\cos(x)(cos^2x+1)}{\sin(x)cos(x)}\]\[= \frac{2\sin^2x}{\sin(x)}\]\[= \frac{2}{\sin(x)} \sin(x) = 2\csc(x) \sin(x)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I'm not sure though, I was laggin ^_^"

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0just go over it please :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0blah~, I'll try again ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0For the record, loco, my answer (sec(x)+cosec(x)  sin(x)) is right, but probably thr wrong form  it's hideous.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sec(x) + cos(x)cot(x), maybe?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0don't know, my school's hw program sucks nuts

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i only get 3 tries per problem

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0That program is retarded, then. Both of the answers I've given are right, but if the form matters then both could be shown as wrong. FFFFUUUUUUUUUUUUU

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0at least it's not timed, i've been doing this since 9pm

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0it really pisses me off and the professor is a b**** and doesn't do anything about it

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol, both of you calm down and just try again ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\frac{\cos x}{\tan x} + \sec x = \frac{\cos^2x}{\sin x} + \sec x = \cos x\cot x + \sec x = ?\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Which can also be written as sec x + csc x  sin x , and many other things.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i'll wait for sstarica's answer

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0True, she (I think, but maybe he?) does have more fans than me, so that's a good call.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0just to make sure, what is the question loco? :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Simplify the trigonometric expression. cos[x]/ tan[x] + sec[x]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0what on earth? lol what kind of quetion is that? >_>

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0idk.... curious loco mind

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Don't worry about loco the sexpest . But in answer to the question of course she is, she does Maths.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok... lets continue with math. i don't wanna go to jail

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I got : cscx sinx + secx *sigh* not sure though, but that's what I got

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0cos^2x + 1  sinx

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Blexting is about to say : This problem is trivial via the use of synthetic division.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Blexting sec x is not 1 / sin x, btw.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0check mine please ^^" if I'm wrong, then I'm sorry

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0My answer (which sstarica now has, too) has been right all along.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok this the last try i have left any final answers

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol INew, you got the same answer? :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The answer =sec x + csc x  sin x =sec x + cos x cot x Now guess which is the required form :D Yes, got it above.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oh, I'm a she. Hence the Newton name and everythi oh, wait a second ...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol, then loco go with it, I got the same answer too ^_^, damn my body temperature increased, too much concentration ^^"

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0nope it didn't work. sorry guys. told u the system is bs

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i got a 90 on the quiz though

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Out of interest, what level is the quiz? As in, what educational level?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0THANKS FOR TRYING NEWTON (HE OR SHE?) AND SSTARICA (SEND ME UR # ;p)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lok, someone answered this question in the other thread >_< LOL!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0but the professor is really tough, doesn't curve or anything

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oh, I'm english, so these american maths terms mean nothing to me ¬_¬ And trust me, that wasn't me trying.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0american ed system succks retricemate

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Don't worry, the person on the other thread got it wrong.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol, relax, so what if the teaher sucks? depend on yourself and trust your abilities :), I had the worse teachers, so I had to depend on myself and look where I've reached :) good luck loco ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0for my own personal interest, where have you reaced?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0"Look where I've reached"  I thought that meant a title/place, but now I think about I think it just means an ability level. My bad.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i think it can mean both. depends on what you're talking about
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