填空题 (共 3 题 ),请把答案直接填写在答题纸上
设 $f(x)=\left\{\begin{array}{cc}x e^{x^2}, & -\frac{1}{2} \leq x < \frac{1}{2} \\ -1, & x \geq \frac{1}{2}\end{array}\right.$ ,则 $\int_{\frac{1}{2}}^2 f(x-1) \mathrm{d} x=$
$\int_0^1 \frac{x \mathrm{~d} x}{\left(2-x^2\right) \sqrt{1-x^2}}=$
$\int_1^2 \frac{1}{x^3} e^{\frac{1}{x}} \mathrm{~d} x=$