in need of assistance!
Find the exact value for x if cos^2x=1/2sin 2x

Question

tkhunny · Answer

$\sin(2x) = 2\sin(x)\cos(x)$ -- That should help.

anonymous · Answer

Could you stay here so when I get the answer I can check it with you?

anonymous · Answer

X represents degrees, not a numerical answer, not sure if that effects it. . .

tkhunny · Answer

You should get over trying to make that a distinction for anything.  It is entirely insignificant.

anonymous · Answer

Alrighty

tkhunny · Answer

Well, how's it going?

anonymous · Answer

I came up with x=0,90,45,225 degrees

tkhunny · Answer

Sure wish I knew how you came up with those.  You didn't share much.

If you had shared, I might be able to tell you how you managed 90º instead of the correct 180º.

anonymous · Answer

To be honest I'm not sure where I went wrong, I came up with cos x=o, but I was going through the steps my book displays.

tkhunny · Answer

$\cos(x) = 0 \implies x = 90º\;or\;x = 270º$

You didn't fall for my little joke.  90º was good.  0º wasn't.

anonymous · Answer

Oh I see, I think I get it now, I just need help getting a problem started. I have two more similar problems would you be able to assist me with those ones? If you cannot I understand.

tkhunny · Answer

Post on a new thread.  Tag me if you like.

anonymous · Answer

Alright, thank you! You're a life saver!

tkhunny · Answer

I've been called worse.  :-)