Originally Posted by

**Daddy_Long_Legs** Calculus26,

I was meaning do I differentiate it with respect to m1m2 and then D or m1,m2 and then D. I was wondering this because they only give you one % error for m1 and m2 and so I thought this may be a single function.

Differentiating with respect to m1m2 and the D and then using the percentage errors given m1m2 %5 and the D 4% I found the percentage error in F to be 13%

I seems what you have done is differentiate with respect to m1, m2 and then D, and used 5% error for m1 and m2 and then 4% error for D.

This was my question. I'm not sure if I have to differentiate with respect to m1m2 and D or m1, m2 and D.