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Consider the following integrals:
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(a) $\displaystyle{\int \frac{5x}{\sqrt{9-4x^2}}\ dx}$ & \hspace*{2em} & (b) $\displaystyle{\int \frac{3}{\sqrt{9-4x^2}}\ dx}$ & \hspace*{2em} & (c) $\displaystyle{\int \frac{2x^3}{\sqrt{9-4x^2}}\ dx}$
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Each of these integrals can be evaluated using the substitution method.  For each of the integrals (1) write out the $u$-substitution and (2) evaluate the integral.  Be careful with your notation - it will be graded.
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