i.i.5 Potential and solenoidal fields

Condition: Show that the vector field \[ \vec{a}=\left(e^{x}+\frac{1}{z}\right) \vec{\imath}+\left(\frac{1}{z}+\frac{1}{y}\right) \vec{\jmath}+\left(e^{z}-\frac{x+y}{z^{2}}\right) \vec{k} \] is potential and find its potential.