Trig Functions Squared: Solving for cos2 0 = 1/2 with Homework Equations

[MadmanMurray]

Homework Statement

cos² 0 = 1/2 (0 for angle)

Homework Equations

The Attempt at a Solution

I've never seen cos, sin, or tan to the power of anything before what do i do with the power?

 

[rock.freak667]

What you could do is use an the identity $cos 2\theta=2cos^2\theta-1$

OR

put $cos\theta= \pm \frac{1}{\sqrt{2}}$ and then just solve $cos\theta= \frac{1}{\sqrt{2}}$ and $cos\theta= \frac{-1}{\sqrt{2}}$

 

[Unco]

I've never seen cos, sin, or tan to the power of anything before what do i do with the power?

Perhaps you are unfamiliar with the notation: $$\cos^2{\theta}$$ means $$(\cos{\theta})^2$$.

 

[Delphi51]

cos2 0 = 1/2 (0 for angle)

You don't say what you are supposed to do with it!
You could find the value of the angle easily by taking the square root of both sides to get
cos \\theta =
on the left.

 

[Delphi51]

You don't say what you are supposed to find! Maybe the angle?
If you take the square root of both sides you'll get

cos 0
on the left

Can someone tell me how to get a "theta" in this forum?

 

[NoMoreExams]

You can just hit quote and see how others have done it but if you use [ tex] ... [/ tex] tags (obviously without spaces) then to get the symbol theta you would just use \theta

 

[Delphi51]

Thanks! Hope this works . . .
cos $$\theta$$

 

[NoMoreExams]

Instead of doing cos$$\theta$$. I think this looks much nicer:

$$\cos(\theta)$$

You can click on what you are trying to see the TeX "code" for and a box will open telling you the "code"

 

[Delphi51]

Thanks again, NoMoreExams. I actually saw that click on trick before, but it didn't show the [ tex] so I couldn't get it to work.