ecuació diferencial producte derivat

d_{x}[x·f(x)] = ax


f(x)+x·d_{x}[f(x)] = ax


f(x) = (a/2)·x


d_{x}[x·f(x)] = g(x)
f(x)+x·d_{x}[f(x)] = g(x)


f(x) = (1/x)·∫ [ g(x) ] d[x]


d_{x}[x^{n}·f(x)] = g(x)


f(x) = (1/x^{n})·∫ [ g(x) ] d[x]