\(f\left(-1\right)=-5\left(-1\right)-1=5-1=4\\ f\left(0\right)=-5.0-1=-1\\ f\left(1\right)=-5.1-1=-5-1=-6\\ f\left(\dfrac{1}{2}\right)=-5\left(\dfrac{1}{2}\right)-1=\dfrac{-5}{2}-1=\dfrac{-7}{2}\)
Ta có : \(f\left(-1\right)=-5\left(-1\right)-1=5-1=4\)
\(f\left(0\right)=-5.0-1=-1\)
\(f\left(1\right)=-5.1-1=-5-1=-6\)
\(f\left(\dfrac{1}{2}\right)=-\dfrac{5.1}{2}-1=-\dfrac{5}{2}-1=-\dfrac{7}{2}\)