An electromagnetic wave has its electric and magnetic fields given by

$\overrightarrow{E}\left(t\right)={\overrightarrow{E}}_m\sin \left(kx-\omega t\right)$

$\overrightarrow{B}\left(t\right)={\overrightarrow{\mathit{B}}}_{\mathit{m}}\sin \left(kx-\omega t\right)$

If the direction of ${\overrightarrow{\mathit{E}}}_{\mathit{m}}\mathit{ }\& {\overrightarrow{\mathit{B}}}_{\mathit{m}}$ are in the direction of $\hat{\mathrm{i}}+\hat{\mathrm{j}}$ and $\hat{\mathrm{i}}-\hat{\mathrm{j}}$ respectively, the unit vector that gives the direction of propagation of the wave is