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\item[(1)]$\displaystyle\frac{3x-7}{(2x+1)(x^2+4)}=\frac{A}{2x+1}+\frac{Bx+C}{x^2+4}$が成り立つように
定数$A$，$B$，$C$を定めよ．
\item[(2)]$\displaystyle\int_0^2\frac{dx}{x^2+4}$を求めよ．
\item[(3)]$\displaystyle\int_0^2 \left\{ \frac{3x-7}{(2x+1)(x^2+4)}+xe^x \right\} dx$を求めよ．
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