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marasofia1616
 3 years ago
Find the exact value by using a halfangle identity.
sin 22.5°
marasofia1616
 3 years ago
Find the exact value by using a halfangle identity. sin 22.5°

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abb0t
 3 years ago
Best ResponseYou've already chosen the best response.0\[\sin(22.5) = \frac{ 45 }{ 2 }\] use ur double angle formula \[\sin(\frac{ 1 }{ 2 }*x) = 0 \pm \sqrt{\frac{ 1\cos(x) }{ 2 }}\] where x = 45.

abb0t
 3 years ago
Best ResponseYou've already chosen the best response.0Ans: \[\sqrt{\frac{ 2\sqrt{2} }{ 2 }}\]

abb0t
 3 years ago
Best ResponseYou've already chosen the best response.0there should only be a root on the numerator.

marasofia1616
 3 years ago
Best ResponseYou've already chosen the best response.0Ok I got that I had to plug in 45 for the x's in the formula and I got that cos 45= \[\frac{ \sqrt{2} }{ 2 }\] how did you get \[\frac{ \sqrt{2\sqrt{2}} }{ 2 }\]?

marasofia1616
 3 years ago
Best ResponseYou've already chosen the best response.0actually \[\frac{ \sqrt{2\sqrt{2}} }{ 2 }\] is not an option for answers

090909090909
 7 months ago
Best ResponseYou've already chosen the best response.1incorrect, you must convert 22.5 degrees to radians before using the halfangle formula 22.5 degrees = pi/8 radians put it into the formula and get \[\sqrt{(1\cos(\pi/4))/2}\] = \[\sqrt{(1\sqrt{2}/2)/2}\]

090909090909
 7 months ago
Best ResponseYou've already chosen the best response.1the answer simplifies to \[1/2 \sqrt{2\sqrt{2}}\]
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