Two vectors A and B have equal magnitudes. The magnitude of ( A + B ) is ' n ' times the magnitude of ( A - B ). The angle between A and B is:

Two vectors $\displaystyle \vec{A}$ and $\displaystyle \vec{B}$ have equal magnitudes. The magnitude of $\displaystyle (\overrightarrow{\mathrm{A}}+\overrightarrow{\mathrm{B}})$ is ' $\displaystyle n$ ' times the magnitude of $\displaystyle (\overrightarrow{\mathrm{A}}-\overrightarrow{\mathrm{B}})$. The angle between $\displaystyle \vec{A}$ and $\displaystyle \vec{B}$ is :