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anonymous
 one year ago
Check my work if I'm correct.
Find the exact value of sin(11pi/12).
anonymous
 one year ago
Check my work if I'm correct. Find the exact value of sin(11pi/12).

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So I changed it from radians to degrees to make it easier.

hybrik
 one year ago
Best ResponseYou've already chosen the best response.0sin(11(3.1415926535)/12)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I'm not allowed to use the calculator. :)

hybrik
 one year ago
Best ResponseYou've already chosen the best response.0math I just remember first digits of pi so

hybrik
 one year ago
Best ResponseYou've already chosen the best response.0You would just simplify 3.141592/12, which is around 0.26

hybrik
 one year ago
Best ResponseYou've already chosen the best response.0then find the sin of 0.26

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Should I use a reference angle to find 165?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1438110805222:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[= (\sin60\cos45\cos60\sin45)\]

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2i would change negative angle to positive and then use one of de formula

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2i like positive stuff :D

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1438110888230:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1438110954725:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I don't know if I did it right, so what do you guys think?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2okay so i add 360 int 165 360 165 =195 i used sin(a+b) formula \[\huge\rm sin(a+b) =\sin A \times \cos B + \cos A \times \sin B\] \[\sin(45+150) =\sin 45 \cos 150 + \cos 45 \times \sin 150\] \[\sin(45+150) =\frac{ \sqrt{2} }{ 2} \times \frac{ \sqrt{3} }{ 2 }+\frac{ \sqrt{2} }{ 2 }\times \frac{ 1 }{ 2 }\] and got \[\frac{ \sqrt{6} + \sqrt{2 }}{ 4}\] so your answer is correct :D

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2gO_Od job! i almost forgot these stuff ;D

freckles
 one year ago
Best ResponseYou've already chosen the best response.0the cool thing about these is your start doesn't have to match someone elses start that like I would have done it this way: \[\sin(\frac{11\pi}{12}) \\ \text{ sine function is odd } \\ \sin(\frac{11\pi}{12}) \\ \sin(165^o) \\ \sin(120^o+45^o) \\ [\sin(120^o)\cos(45^o)+\sin(45^o) \cos(120^o)] \\ [\frac{\sqrt{3}}{2} \frac{\sqrt{2}}{2}+\frac{\sqrt{2}}{2} \frac{1}{2}] \\ [\frac{\sqrt{6}}{4}\frac{\sqrt{2}}{4}] \\ [\frac{\sqrt{6}\sqrt{2}}{4}] \\ \text{ distribute outside negative } \\ \frac{\sqrt{6}\sqrt{2}}{4} \\ \frac{\sqrt{6}+\sqrt{2}}{4}\]

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2yeah but i wasn't sure that we can take out negative sign \[\sin(\frac{ 11\pi }{ 2 }) > \sin(\frac{ 11\pi }{ 2 })\]

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.2ik sin(x)=sin(x) hmm so that's possible

freckles
 one year ago
Best ResponseYou've already chosen the best response.0right and if we had cos(x) then this is just cos(x) since cos is even

freckles
 one year ago
Best ResponseYou've already chosen the best response.0that is for example \[\cos(\frac{11\pi}{12})=\cos(\frac{11\pi}{12})\]
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