ODE's

This is Differential Equations work. (Mathematics)   

This is not a writing assignment.
 

The assignment is for my use, to review from, but I am having problems with the work and the Professors are not available.
I am hoping a different way of looking at the work will trigger my understanding.
I would appreciate any explanations / steps that could be included on the problems.

You MUST know Differential Equations to do this work.

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