Not sure if the description fits the question I have, but here it goes:

"If a vector functionf(x,y,z) is not irrotational but the product of f and a scalar function g(x,y,z) is irrotational, show that then:

"

I've been working at this for a couple hours now... I was able to find that since:

and

,

then

I don't even know if this is in the right direction. Help!