Question

What is the inverse of y=2x squared -4

Answer 1

$y=2x^2-4\ \ \ |+4\\\\2x^2=y+4\ \ \ |:2\\\\x^2=\dfrac{y+4}{2}\\\\x=\sqrt{\dfrac{y+4}{2}}$

$y^{-1}=\sqrt{\dfrac{x+4}{2}}=\dfrac{\sqrt{x+4}}{\sqrt2}=\dfrac{\sqrt{2(x+4)}}{2}=\dfrac{\sqrt{2x+8}}{2}$