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• lab{7.2.8a} Let [math]n \geq 2[/math] be an integer, and derive a reduction formula for [math]\int \cot^nx x \; dx[/math] analogous to \ref{thm 7.2.1}.
• Use the formula derived in \ref{ex7.2.8a} to integrate [math]\int \cot^5 3\theta \; d\theta[/math].