How do I show there are no elementary function solutions for the differential equation $f''(x)=f(\sqrt{x}), x>0$ in the $C^2(0,\infty)$ space solutions?
How do I show there are no elementary function solutions for the differential equation $f''(x)=f(\sqrt{x}), x>0$?
7
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calculus
real-analysis
analysis
ordinary-differential-equations
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6$f: x \mapsto 0$ is an elementary solution in $C^2$. – 2012-12-05