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anonymous
 one year ago
If sin theta=3/5 and theta is in quadrant 2 determine in exact form sin theta+pi over 6
anonymous
 one year ago
If sin theta=3/5 and theta is in quadrant 2 determine in exact form sin theta+pi over 6

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Loser66
 one year ago
Best ResponseYou've already chosen the best response.1We have formula sin(a+b) = sin a *cos b + sin b *cos a your a = theta your b= pi/6 find cos theta, then plug all into it. dw:1436465382393:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@Loser66 So I did all that and got the answer .9196 but I am off by a point when I check if it is right tho

Loser66
 one year ago
Best ResponseYou've already chosen the best response.1show your work, please

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Alright the end work I got 3sqrt3 over 10 + 2/5 but it doesn't come out correct ___

Loser66
 one year ago
Best ResponseYou've already chosen the best response.1cos (theta) = 4/5 hence sin (theta + pi/6) = sin (theta) cos (pi/6) + sin (pi/6) cos (theta) = (3/5) (sqrt 3/2) + (1/2) (4/5) = 0.573

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0But I still keep getting .919... answer ohmygod this is so frustarting lol @Loser66

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0And when you go to check the answer it is suppose to be .90166

freckles
 one year ago
Best ResponseYou've already chosen the best response.1http://www.wolframalpha.com/input/?i=%283%2F5%29+%28sqrt%283%29%2F2%29+%2B+%281%2F2%29+%284%2F5%29+

freckles
 one year ago
Best ResponseYou've already chosen the best response.1that is what it says when I punch in what loser has above

freckles
 one year ago
Best ResponseYou've already chosen the best response.1and 0.9196 is also what I'm getting

freckles
 one year ago
Best ResponseYou've already chosen the best response.1i think you are right @shortyyshayy

freckles
 one year ago
Best ResponseYou've already chosen the best response.1and they have an error

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@freckles Idk this is coming out weird cuz when checking it I am like a .1 off lol

freckles
 one year ago
Best ResponseYou've already chosen the best response.1just to be sure you are asked to evaluate \[\sin(\theta+\frac{\pi}{6})\]

freckles
 one year ago
Best ResponseYou've already chosen the best response.1well the other thing is it says it wants the EXACT form not an approximation

freckles
 one year ago
Best ResponseYou've already chosen the best response.1exact form would be \[\frac{2}{5}+\frac{3 \sqrt{3}}{10}\]

freckles
 one year ago
Best ResponseYou've already chosen the best response.1which is just an approximation

freckles
 one year ago
Best ResponseYou've already chosen the best response.1I didn't see it said in quadrant 2

freckles
 one year ago
Best ResponseYou've already chosen the best response.1cos is negative there

freckles
 one year ago
Best ResponseYou've already chosen the best response.1\[\frac{3}{5} \frac{\sqrt{3}}{2}+\frac{4}{5}\frac{1}{2}\]

freckles
 one year ago
Best ResponseYou've already chosen the best response.1which actually gives us .1196 so that still doesn't give us the answer you want

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0where did you get 4/5 from tho??

freckles
 one year ago
Best ResponseYou've already chosen the best response.1it says theta is in quadrant 2

freckles
 one year ago
Best ResponseYou've already chosen the best response.1cos is negative there and sin is positive there

freckles
 one year ago
Best ResponseYou've already chosen the best response.1sin(theta)=3/5 cos(theta) can be 4/5 or 4/5 depending on where theta is

freckles
 one year ago
Best ResponseYou've already chosen the best response.1and since cos is negative then cos(theta)=4/5

freckles
 one year ago
Best ResponseYou've already chosen the best response.1here is another way to look at it we are given sin(theta)=3/5 \[\cos^2(\theta)+\sin^2(\theta)=1 \\ \cos^2(\theta)+(\frac{3}{5})^2=1 \\ \cos^2(\theta)+\frac{9}{25}=1 \\ \cos^2(\theta)=1\frac{9}{25} \\ \cos^2(\theta)=\frac{25}{25}\frac{9}{25} \\ \cos^2(\theta)=\frac{16}{25} \\ \cos(\theta)=\pm \sqrt{\frac{16}{25}} \\ \cos(\theta)=\pm \frac{4}{5}\]

freckles
 one year ago
Best ResponseYou've already chosen the best response.1now deciding whether to use 4/5 or 4/5 entirely depends on where theta is

freckles
 one year ago
Best ResponseYou've already chosen the best response.1dw:1436467227803:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@freckles ohhh alright i think this is making more sense now! haha thanks so much!!!

freckles
 one year ago
Best ResponseYou've already chosen the best response.1dw:1436467279746:dw

freckles
 one year ago
Best ResponseYou've already chosen the best response.1hey so why are you looking for an approximation anyways?

freckles
 one year ago
Best ResponseYou've already chosen the best response.1you problem wants exact form

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I thought thats what it wanted in the first place lol

freckles
 one year ago
Best ResponseYou've already chosen the best response.1\[\frac{3}{5} \frac{\sqrt{3}}{2}+\frac{4}{5}\frac{1}{2} \\ \frac{3 \sqrt{3}}{10}\frac{2}{5}\] this is exact form

freckles
 one year ago
Best ResponseYou've already chosen the best response.1like the .1196 is an approximation to that exact form

freckles
 one year ago
Best ResponseYou've already chosen the best response.1.1196 is not exactly 3sqrt(3)/102/5 that is the funny thing about irrational numbers
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