Derivative Troubles: A Scientist's Dilemma?

[Garlic]

Hello PF,

1. Homework Statement

I've been having problems with the deriative of a function, although I thought I've done everything right, my solution doesn't match with the right solution. I have no clue what (or if) I've done anything wrong, or simply don't know the tricks I was supposed to use.

Homework Equations

+ 3. The Attempt at a Solution [/B]

 

[Garlic]

Okay, so it appears, that I haven't correctly derived the function at the beginning, so the problem begins with the first row.

 

[sunnnystrong]

Foil everything... Than you're just going to be using the chain rule

 

[sunnnystrong]

Take the derivative with respect to t

 

[Garlic]

Thank you!