Question

what is the axis of symmetry for y= 4x^2-1???

Answer 1

Now to find the axis of symmetry, one must first know the equation one is working with. In this case, the equation is in the form of:
y=ax^2+bx+c
To find the axis of symmetry, all you need to do is plug the coefficients a and b into the equation:
-b/2a
This will give you the axis of symmetry. If you want to go a step further, you may plug the x value back into the equation for x and solve for y to find the vertex.
The answer to this is tricky because there seems to be no b term, but there is technically.
y=4x^2-1 is actually y=4x^2+0x-1, which means your b value is 0, and your a value is 4. Plug into the equation, and you get -0/8, which is simply 0.