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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