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vaibhavtewari
Jul29-11, 10:44 AM
When I try
Simplify[Sqrt[1/(c^2 L^2 - k^2 q^2 Q^2)] Sqrt[c^2 L^2 - k^2 q^2 Q^2],
c^2 L^2 - k^2 q^2 Q^2 > 0]
I get
Sqrt[1/(c^2 L^2 - k^2 q^2 Q^2)] Sqrt[c^2 L^2 - k^2 q^2 Q^2]
as output

but when I try
Simplify[Sqrt[1/(c^2 L^2 - k^2 Q^2)] Sqrt[c^2 L^2 - k^2 Q^2],
c^2 L^2 - k^2 Q^2 > 0]
I get
1
as output. Can someone resolve is that a bug or I am doing something wrong.

Thank You,

Simon_Tyler
Jul29-11, 07:16 PM
It's not a bug, in that the answer is not actually wrong... Mma gets confused when there's too many terms, especially in integrals with too many constants that are grouped together. If you run into problems like this where you know there is a group of terms that often occurs, sometimes you need to help it along.

Simplify[Sqrt[1/(c^2 L^2 - k^2 q^2 Q^2)] Sqrt[c^2 L^2 - k^2 q^2 Q^2],
c^2 L^2 > k^2 q^2 Q^2]
(* doesn't work, so help it with *)
Simplify[% /. c^2 L^2 -> a + k^2 q^2 Q^2, a > 0]