Answer
Vertex: $(0, -1)$
x-intercepts:$(-1/2,0)$, $(1/2,0)$
y-intercept: $(0,-1)$
Work Step by Step
$f(x)=4x^2-1$
$a=4$, $b=0$, $c=-1$
Vertex is at $x=-b/2a$
$x=-0/2*4$
$x=-0/8$
$x=0$
$x=0$
$f(x)=4x^2-1$
$f(0)=4*0^2-1$
$f(0)=4*0-1$
$f(0)=0-1$
$f(0)=-1$
$(0, -1)$ is the vertex and the y-intercept
$y=0$
$f(x)=4x^2-1$
$0 =4x^2-1$
$0+1=4x^2-1+1$
$1=4x^2$
$1/4=4x^2/4$
$1/4=x^2$
$\sqrt {1/4} = \sqrt {x^2}$
$±1/2 =x$
$x=1/2$
$f(x)=4x^2-1$
$f(1/2)=4*(1/2)^2-1$
$f(1/2)=4*1/4-1$
$f(1/2)=1-1$
$f(1/2)=0$
$x=-1/2$
$f(x)=4x^2-1$
$f(-1/2)=4*(-1/2)^2-1$
$f(-1/2)=4*1/4-1$
$f(-1/2)=1-1$
$f(-1/2)=0$
