Please help me

If this is exactly the way the problem looks, then it means the same as

[MATH]\frac{1}{P[1]} - \frac{1}{P[2]}[/MATH]​

If the goal is to simplify it, all you can do is to combine the fractions using a common denominator.

But if P[1] and P[2] have been defined, then there may be more to do, using their meanings.

Please follow our guidelines by telling us the context of the question and stating it fully, and also showing whatever work you can do, and where you are stuck.
 
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