The function is .
.
Apply partial fraction decomposition.
\.
Equate coefficients.
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Equate constant terms.
\Substitute .
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Substitute in
.
.
Substitute and
in
.
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Find the power series.
\Apply the power series formula: .
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The power series representation of .
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The series is in the form of geometric series.
\The series is converges when .
The power series representation of .
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is geometric series.
The series is converges when .
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Consider .
The interval of convergence of is
is
.
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The interval of convergence is .