Ey=E0sin(kx−ωt), Ez=4E0sin(kx−ωt),

the magnetic field can be written in the following way

B =[ sin(ωt+(−1)bBkx)(cBxˆ+dByˆ+eBzˆ)]
In other words: Bx=cBsin(ωt+(−1)bBkx), By=dBsin(ωt+(−1)bBkx), Bz=eBsin(ωt+(−1)bBkx)

Find :

dB . Express it in terms of E0, c
eB . Express it in terms of E0, c