A Function of a Function
Date: 6/19/96 at 14:51:12 From: Scott Turner Subject: A Function of a Function You answered my last question so quickly. I am so impressed. Thanks so much for the help. Here is another one. I understand the concept but I don't know how to put it into words: Suppose that f(x) is O(g(x)). Does it follow that 2 to the power f(x) is O(2 to the power g(x))? Again, thanks for your invaluable service. ST
Date: 6/20/96 at 13:51:3 From: Doctor Tom Subject: Re: A Function of a Function Nope. Let f(x) = 2x and g(x) = x. f = O(g) since for large x, f(x) < 2.1*g(x). But there's no constant M such that 2^(2x) < M*2^x. If so, M must be greater than 2^x, for all x, which is clearly impossible. -Doctor Tom, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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