How do they derive from equation A to B?

timeforchg

My question is how to get from equation A to B.
By using partial fractions? differential? any methods?

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DonAntonio

Don't use attachments as it makes very cumbersome reading the question and answering it. Write down the stuff using LaTeX for mathematics.

DonAntonio

chiro

Hey timeforchg and welcome to the forums

Do you have any conditions? Are you assuming A = B and trying to go from A to B while maintaining an equality?

timeforchg

yes. I think is more simplifying the equation.

I am trying to find the limit z = 0. When I see inside my text before they use l'hopital rule, they simplified the equation A to B. Thereafter they apply the l'hopital rule

chiro

Ohh, next time you use a limit please specify this in the equation so there is no ambiguity or confusion.

I have a feeling you have got the equation wrong: if you take the limit in this case to go to zero, the top goes to 0 but the bottom doesn't (it goes to 3-j which may not be zero and is only zero if 3 = j).

timeforchg

there is no + in eq A for the denominator

chiro

Can you please write out the expression on the denominator?

timeforchg

SOLVED!! Thanks a lot guys!! Appreciate it.