Here is an example of how to do partial fractions using the cover-up method

Question

anonymous · Answer

attachment

anonymous · Answer

This was generated from my site http://www.saab.org/mathonline/

tkhunny · Answer

Though it works, I really do not like this method that requires us to multiply by values that are NOT in the Domain.  It is a very odd thing.  Again, I cannot argue that it works, only the validity of its existence.

anonymous · Answer

It is valid. It is faster and more efficient.

anonymous · Answer

These values are called removable singularities and when you multiply by the right factor, you remove the corresponding singularity.

anonymous · Answer

http://en.wikipedia.org/wiki/Heaviside_cover-up_method

tkhunny · Answer

No, they are not Removable Singularities.  If you intended to use the new function, with the singularity removed, I would agree.  As you intend to retain the singularity, then I cannot agree with you.  The "right factor" you mention is zero.

Again, it works.  I just don't like it.  It shouldn't exist, but there it is.

anonymous · Answer

it is you right to not like something, but this will not make a method that has been used for ages not correct.

tkhunny · Answer

I dare you to show me where I said it wasn't correct or didn't work.  :-)