a: f(-1)=5-3=2
f(3/2)=-15/2-3=-21/2
b: y=-8 thì -5x-3=-8
=>-5x=-5
hay x=1
y=0 thì -5x-3=0
=>-5x=3
hay x=-3/5
\(a.f\left(-1\right)=\left(-5\right).\left(-1\right)-3=5-3=2\\ f\left(\dfrac{3}{2}\right)=\left(-5\right).\dfrac{3}{2}-3=-\dfrac{15}{2}-3=-12\)
a. f(-1) y=-5.-1-3=> y= 2
f(3/2) y= -10.5
b y= -8 => -8=-5x-3 => x=-1
y=0 => x= -3/5
y=f(-1)=-5(-1)-3=5-3=2
y=f(3/2)=-5(3/2)-3=-15/2-3=-12
a) f(-1) = -5.(-1) - 3 = 5 - 3 = 2
b) \(f\left(\dfrac{3}{2}\right)=-5.\dfrac{3}{2}-3=-\dfrac{15}{2}-\dfrac{6}{2}=-\dfrac{21}{2}\)
b) *) \(y=-8\Rightarrow-5x-3=-8\)
\(-5x=-8+3\)
\(-5x=-5\)
\(x=1\)
*) \(y=0\Rightarrow-5x-3=0\)
\(-5x=3\)
\(x=-\dfrac{3}{5}\)
