HW#4
M&T Problem 2-43

To find the potential function, we simply integrate the negative of the force dot the differential distance:
	
	
	
	
	
	
	
	
	
Checking with Mathematica.

\(Clear[a, k]; 
\(-Integrate[\(-k\)\ x\  + \ k\ x^3/a^2, x]\)\)

\(a = 1; 
k = 1; 

    Plot[\(k\ x\^2\)\/2 - \(k\ x\^4\)\/\(4\ a\^2\), {x, \(-2\), 2}]\)