T
tht_102


Bài 1 : Chứng minh các Bất đẳng thức sau :
[TEX]a, \ \frac12 \ ( \sqrt{lna} + \sqrt{lnb} ) \ \le \ \sqrt{ln{\frac{a+b}{2}}}[/TEX]
[TEX]b, \ 2^{2. sinx} + 2^{tanx} > \ \ 2^{\frac{3x}{2} +1}[/TEX]
[TEX]c, \ e^x + cosx > \ \ 2 + x+ - \frac{x^2}{2}[/TEX]
[TEX]a, \ \frac12 \ ( \sqrt{lna} + \sqrt{lnb} ) \ \le \ \sqrt{ln{\frac{a+b}{2}}}[/TEX]
[TEX]b, \ 2^{2. sinx} + 2^{tanx} > \ \ 2^{\frac{3x}{2} +1}[/TEX]
[TEX]c, \ e^x + cosx > \ \ 2 + x+ - \frac{x^2}{2}[/TEX]