\(P=\dfrac{17}{5-\left|2x-3\right|}\)
\(\left|2x-3\right|\ge0\forall x\)
\(\Rightarrow5-\left|2x-3\right|\le5\)
\(P=\dfrac{17}{5-\left|2x-3\right|}\ge\dfrac{17}{5}\)
Dấu "=" xảy ra khi:
\(\left|2x-3\right|=0\Rightarrow2x=3\Rightarrow x=\dfrac{3}{2}\)
\(Q=\dfrac{14-x}{4-x}=\dfrac{4-x+10}{4-x}=\dfrac{4-x}{4-x}+\dfrac{10}{4-x}\)
\(Q=1+\dfrac{10}{4-x}\)
\(MIN_Q\Rightarrow MIN_{\dfrac{10}{4-x}}\Rightarrow MAX_{4-x}\)
\(\Rightarrow4-x=-1\Rightarrow x=5\)
\(MIN_Q=1+-10=-9\)
Xảy ra khi \(x=5\)
Đúng 0
Bình luận (0)
