Inverse functions.

I know there are inverse functions to quartic equations that can be
expressed in simple terms, just like there are inverse functions to
cubic equations that can be expressed in simple terms. Basically,
rather than using roots within roots, I'm looking for something
simpler. The question is, what can possibly be simpler than roots
within roots?

I asked a question similar to this earlier, but did not reveal my goal.
Now my goal is revealed. What's the simplest way to find the inverse
function of quartic equations? I've already found it for cubic and it's
something that's been known a while.

I think it would involve sines, cosines, their hyperbolic equivilents,
and the inverses of all of those. I know that makes it sound more
complex than it normally would be, but trust me it's simpler that way.

BTW, the reason I'm posting this is because my other message
disappeared somehow, or I just can't find it. Sorry about that. I just
really need the answer to that question.

.