On Sun, 16 Sep 2001, David J Binnington wrote:

> Can anybody give me a kick start with this?

David,


You can re-write your equation like:

Z = 10*lg(x^2 + y^2)
  = 10*lg(x^2 * ( 1 + (y/x)^2))
  = 20*lg(x) + 10 * lg( 1 + (y/x)^2)

let v = 1+(y/x)^2

Z = 20*lg(x) + 10*lg(v)

I'd factor it this way if x is greater than y. If y is larger, then factor
it out instead.

Does that help?

Scott

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