Question

Is this correct? Or would there be no (-) sign before the square root?

Answer 1

When I was doing the problem, I completely forgot to include the + and - sings, so by the time I was finished I went back and I wasn't sure

Answer 2

\[cos(210/2)=\sqrt{\frac{1+cos(210)}{2}}\]

Answer 3

+- in front

Answer 4

Yes

Answer 5

\[cos(105)=\pm \sqrt{\frac{1+cos(\frac{7\pi}{6})}{2}}\]

Answer 6

You are right. There is a minus sign in front. Because cos 105 is in the 2nd quadrant and it is negative.

Answer 7

seems right

Answer 8

Alrighty (: Thank you everyone!