Partial fractions (for laplace) (1 Viewer)

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

1. The problem statement, all variables and given/known data
This problem is killing me.

I need to bust this thing up using partial fractions.


2. Relevant equations

3. The attempt at a solution

I'm leaning towards it being separated like this. Is this correct?

If it is, I'm not exactly sure what I'm supposed to do next.
Last edited:
145s/ [(s+2j)(s-2j)(s-2+3j)(s-2-3j)]
Make sure above is correct .. now

[145s / (s-2j)(s-2+3j)(s-2-3j) ]*1/ [(s+2j)]
[145s / (s+2j)(s-2+3j)(s-2-3j) ]*1/ [(s-2j)]
[145s / (s-2j)(s+2j)(s-2-3j) ]*1/ [(s-2+3j)]
[145s / (s-2j)(s+2j)(s-2+3j) ]*1/ [(s-2-3j)]

I believe what I did above should be self explanatory. Now next step is to substitute s=-2j to [145s / (s-2j)(s-2+3j)(s-2-3j) ]
s=2j to [145s / (s+2j)(s-2+3j)(s-2-3j) ]
s = 2-3j in the third, and s=2+3j .. so on, You leave one of the simplest possible factor in the denominator taking all others to the numerator and then substituting the root.

See if that works :biggrin:
I'll try that, thanks :approve:
I'll try that, thanks :approve:
Answering your question in the OP, you had that correct. But, I just wanted to share a new tool I discovered in Calc III class which I think is very helpful for partial fractions.

The Physics Forums Way

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving