Initially two particles A and B are present at (0, 0) and (d, 0) respectively. They start moving with speed ${\mathrm{v}}_{\mathrm{A}}=\mathrm{v}\hat{\mathrm{i}}+\mathrm{v}\hat{\mathrm{j}}\text{ and }{\mathrm{v}}_{\mathrm{B}}=-\mathrm{v}\hat{\mathrm{j}}$. If R is magnitude of relative separation between them and T₀ be the time when separation between them is minimum, then