[再寄小读者之数学篇](2014-06-23 Bernstein's inequality)

$$\bex \supp \hat u\subset \sed{2^{j-2}\leq |\xi|\leq 2^j} \ra \cfrac{1}{C}2^{jk}\sen{f}_{L^p} \leq \sen{D^k f}_{L^p}\leq C2^{jk} \sen{f}_{L^p}; \eex$$ $$\bex \supp \hat u\subset \sed{|\xi|\leq 2^j} \ra \sen{f}_{L^q}\leq C2^{jn\sex{\frac{1}{p}-\frac{1}{q}}} \sen{f}_{L^p}\quad\sex{1\leq p\leq q\leq \infty}. \eex$$  see [D. Chae, J. Lee, On the blow-up criterion and small data global existence for the Hall-magnetohydrodynamics, J. Differential Equations, 256 (2014), 3835--3858].

上一篇:[再寄小读者之数学篇](2014-06-20 求极限-H\"older 不等式的应用)


下一篇:[再寄小读者之数学篇](2014-04-08 from 1297503521@qq.com $\sin x-x\cos x=0$ 的根的估计)