Question

Help with Half Angle

Answer 1

What is the angle?

Answer 2

@Mertsj

Answer 3

btw I tried and got the answer \[-\frac{ \sqrt{2+\sqrt{2}} }{ 2 }\]

Answer 4

yea i would say that is right sorry i couldn't help lol

Answer 5

@e.mccormick can you help?

Answer 6

OK, so you know your half angle formula?

Answer 7

yes

Answer 8

Also, even odd on that cosine... so you can just call it even.

Answer 9

why is it even?

Answer 10

\(\cos(-\theta)=\cos(\theta)\) Even odd properties.

Answer 11

okay got it

Answer 12

did you use something like \(\sin^2\theta =\frac{1}{2}(1-\cos(2\theta))\)

Answer 13

no I used \[\sqrt{\frac{ 1-\cos x }{ 2 }}\]

Answer 14

Ag, well, the cosine evrsion... which would be 1+ rather than - in this case...

Answer 15

is that the same thing?

Answer 16

yes sorry, looked at the wrong one

Answer 17

To use the one you listed, you need to be able to divide the input angle. But your input angle has a fraction you want to get rid of...

Answer 18

i did this