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QUESTION

Find an integrating factor for the differential equation
$\ds\frac{dx}{dt}-\frac{x}{t}=t^2$. (Do NOT solve the equation).

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ANSWER

The integrating factor is
$\ds\exp\left(\int-\frac{1}{t}\,dt\right)=\exp(-\ln
t)=\exp\left(\ln t^{-1}\right)=\frac{1}{t}$




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