科数网
试题ID
41111
所属试卷
科数网-一元导数微分学
试题
设 $\left\{\begin{array}{l}x=\sqrt{t^2+1}, \\ y=\ln \left(t+\sqrt{t^2+1}\right),\end{array}\right.$ 则 $\left.\frac{\mathrm{d}^2 y}{\mathrm{~d} x^2}\right|_{t=1}=$
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