Finding Limits in Fourier Series: How Do the Left and Right Hand Limits Work?

[NotStine]

Homework Statement

Please see attached image. From the given information, I am having trouble deriving the left and right hand limits, I just can't figure out what these are...

http://img176.imageshack.us/img176/9334/fstih3.png

Homework Equations

None needed.

The Attempt at a Solution

In the solution, t is chosen as pi, which I understand. But I just can't figure out how these left and right hand limits are found. Are these limits somehow derived from limits of integration?

Here is the solution.

http://img176.imageshack.us/img176/2899/fst2yg0.png

Any help will be appreciated.

 

[Dick]

The limits are derived by looking at the original definition of the function. For 0<t<pi, f(t)=t^2. So as t->pi from below f(t)->pi^2. For pi<t<2*pi, f(t)=0. So as t->pi from above f(t)=0.