Question

Giúp m giải bài 1,2 với ah!!!!!

Answer 1

1.

\(P=\dfrac{3}{\sqrt{x}+3}\le\dfrac{3}{0+3}=1\)

\(\Rightarrow maxP=1\Leftrightarrow x=0\)

2. 

\(A=\dfrac{2\sqrt{x}-1}{\sqrt{x}+1}=\dfrac{2\left(\sqrt{x}+1\right)-3}{\sqrt{x}+1}=2-\dfrac{3}{\sqrt{x}+1}\ge2-\dfrac{3}{0+1}=-1\)

\(\Rightarrow minA=-1\Leftrightarrow x=0\)