if [itex]\alpha, \alpha' \in \Omega^1[/itex]. Rewrite the identity, [itex]d(\alpha \wedge \alpha')=d \alpha \wedge \alpha' - \alpha \wedge d \alpha'[/itex] in terms of vector calculus. I have absolutely no idea what is going on here. So if anybody could explain to me a) what this is all about and b) how to go about doing it, that would be great. Cheers.