bn vô danh giúp mik với ;-;

a) f(0)= -5: f(-1)= -3: f(căn 2)= -1: f(-1/2)= -6

b) y= -5 thì x=0: y= 3 thì x= 2: y= -1 thì x=1.414213562: y= -6 thì x= Không tính được

Hàm \(f\left(\left|x\right|\right)\) có 5 điểm cực trị khi \(f\left(x\right)\) có 2 cực trị dương

\(\Rightarrow f'\left(x\right)=3x^2-4x+2-m=0\) có 2 nghiệm dương phân biệt

\(\Rightarrow\left\{{}\begin{matrix}\Delta'=4-3\left(2-m\right)>0\\x_1+x_2=\dfrac{4}{3}>0\\x_1x_2=\dfrac{2-m}{3}>0\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}m>\dfrac{2}{3}\\m< 2\end{matrix}\right.\) \(\Rightarrow\dfrac{2}{3}< m< 2\)

\(y=f\left(x\right)=\dfrac{5}{x-1}\)

a) ĐKXĐ khi: \(x-1\ne0\) \(\Leftrightarrow x\ne1\)

b)

\(y=f\left(-2\right)=\dfrac{5}{-2-1}=\dfrac{5}{-\left(2+1\right)}=\dfrac{5}{-3}=\dfrac{-5}{3}\)

\(y=f\left(\dfrac{1}{3}\right)=\dfrac{5}{\dfrac{1}{3}-1}=\dfrac{5}{\dfrac{1}{3}-\dfrac{3}{3}}=\dfrac{5}{\dfrac{-2}{3}}=\dfrac{-15}{2}\)

c)

* \(y=f\left(x\right)=\dfrac{5}{x-1}=-1\)

\(\Rightarrow x-1=5:\left(-1\right)\)

\(\Rightarrow x-1=-5\)

\(\Rightarrow x=-5+1\)

\(\Rightarrow x=-\left(5-1\right)\)

\(\Rightarrow x=-4\)

Vậy \(y=-1\) thì \(x=-4\)

* \(y=f\left(x\right)=\dfrac{5}{x-1}=1\)

\(\Rightarrow x-1=5:1\)

\(\Rightarrow x-1=5\)

\(\Rightarrow x=5+1\)

\(\Rightarrow x=6\)

Vậy \(y=1\) thì \(x=6\)

* \(y=f\left(x\right)=\dfrac{5}{x-1}=\dfrac{1}{5}\)

\(\Rightarrow x-1=5:\dfrac{1}{5}\)

\(\Rightarrow x-1=5.5\)

\(\Rightarrow x-1=25\)

\(\Rightarrow x=25+1\)

\(\Rightarrow x=26\)

Vậy \(y=\dfrac{1}{5}\) thì \(x=26\)