Deriving the Equation for Period of Simple Pendulum? Is my attempt correct?

[amd123]

Homework Statement

I have to derive an equation with the following variables:
T= period
m= mass
Theta= angle
l= length

and I was told to think of the period as the perimeter of a circle.

Homework Equations

The Attempt at a Solution

$$C=2\pi r,C/2=\pi r,d=\pi r,(at^2)/2=\pi r,t=\sqrt{\frac{2\pi r}{Ef/m}},t=\sqrt{\frac{2\pi rm}{sin\Theta r }}$$

 

[rock.freak667]

It is simpler to just draw the pendulum's arc and then use then use the tangential component as the resultant force (F=ma).

This will help you prove that for small angles, the motion is simple harmonic and then the period will be easier to find.

 

[amd123]

I have not come across any of the terminology you have just said.
I doubt I would be allowed to use that method.

Could you describe it in another way or comment on my attempt?