# laplace help please very urgent

• Nov 17th 2008, 11:33 AM
darren1971
laplace help please very urgent
Please can someone help me out of my misery.

My question is how can I solve this equation:

2CE e-3at u(t)-u(t-2t)

I have replaced t with t= [(t-2T)+2T]

now I have q(t) = 2CE e-3a[(t-2T)+2T] u[(t-2T)+2T]-u(t-2T)

so I have crossed out the delay of 2T = e-2Ts

so I am left with q(t) = 2CE e-3a(t+2T) u(t+2T)-u(t)

I am now lost and have no idea what to do next.

Please can someone put me out of my misery.
• Nov 17th 2008, 05:22 PM
mr fantastic
Quote:

Originally Posted by darren1971
Please can someone help me out of my misery.

My question is how can I solve this equation:

2CE e-3at u(t)-u(t-2t)

I have replaced t with t= [(t-2T)+2T]

now I have q(t) = 2CE e-3a[(t-2T)+2T] u[(t-2T)+2T]-u(t-2T)

so I have crossed out the delay of 2T = e-2Ts

so I am left with q(t) = 2CE e-3a(t+2T) u(t+2T)-u(t)

I am now lost and have no idea what to do next.

Please can someone put me out of my misery.

No-one has probably replied so far because, like me, they can't make sense of what you've posted. Problems with what you've posted include (but are not limited to):

1. There's no equation given to solve. Equations have an equal sign (=) in them.

2. What is CE meant to represent?

3. Is e-3at meant to be \$\displaystyle e^{-3at}\$. If so, it should at least be written as e^(-3at).

4. "I have replaced t with t= [(t-2T)+2T]" makes no sense.

If you want help, especially urgent help, you will need to be much much clearer.