Hi, here's my question...We have to determine whether or not the formulas down there are numerically stable for the cases where x >=0 and x<0. I say that the formulas are stable for x>=0 but not for x<0 because you are subracting numbers that could be close to each other. My problem is that I am having a really hard time writing a new formula that is numerically stable for negative x values. See if you can point me down the right path.(adsbygoogle = window.adsbygoogle || []).push({});

the formulas are:

u= +-sqrt((x+sqrt(x^2+y^2)))/2)

v=y/2u

Thanks for any help that you can give,

CC

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# Homework Help: Numerical stability

Can you offer guidance or do you also need help?

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