Suppose you had an equation like this:

5X + 3Y * (4Sin(N)-Sqrt(T)) + 7 = V

And you also had 30 values for each of X, Y, N, and T. How would you evaluate the equation?

I have a technique to do this, and considered explaining it, but decided it just got in the way. For this simple example, my technique is very fast, but once the equations can include over two dozen variables, as opposed to just four as in this example, the performance starts to slow. In some cases, it slows greatly. I suspect, though I have no proof of this yet, that it might have to do with multiple nested parentheses in the equations.

So, what I'm looking for is whether or not there is some technique for evaluating equations of nearly arbitrary length, where there can be geometric, and some fairly simple exponential and logarithmic transformations of individual variables?

EDIT: Oh, yeah, I should also mention, there will be some 300 million of these equations to evaluate, so speed is crucial.