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(1) $\int \dfrac {1}{x^{2}} \tan ^{2} \dfrac {1}{x}dx= \underline { \quad \quad \quad }$.

(2)$ \int (1- \dfrac {1}{x^{2}})e^{x+ \frac {1}{x}}dx= \underline { \quad \quad \quad }$.
                        
不再提醒