The perceived star density is .
The actual density of stars in a cluster is .
Find the perceived density .
Substitute in
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Solve the integral by using parts of integration method.
\Formula for integration by parts :.
and
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Consider .
Apply derivative on each side with respect to .
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Consider .
Apply integral on each side.
\Let .
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Substitute and
in
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Substitute .
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Substitute the corresponding values in .
Apply formula: .
Apply formula:.
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The perceived density .
The perceived density .