for the second question should i be using taylors series?
How would I show that
(cond f X g)(x) <= (cond f)(x) + (cond g)(x)
am I right to assume that (cond f)(x)= (X x f(prime)(X))/f(X)
Also how would I analyze the error propagation in the exponent x^a (x>0)
1. x is exact and a is subject to a small error
2. a is exact and x is subject to small error