The function is .
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Apply partial fraction decomposition.
\.
Equate coefficients.
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Equate constant terms.
\Substitute .
Substitute in
.
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Substitute and
in
.
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Find the power series for .
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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Find the interval of convergence using ratio test.
\Consider and
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The series is converges when .
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The interval of convergence of is
.
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The interval of convergence is .