Question 185447
There's a problem here: the equation {{{y=2x^2-3}}} has no inverse over the domain *[Tex \LARGE \left(-\infty,\infty\right)]. However, if we restrict the domain to be <font size="6">[</font>*[Tex \LARGE 0,\infty]<font size="6">)</font>, then we can find the inverse.



So...

Domain: <font size="6">[</font>*[Tex \LARGE 0,\infty]<font size="6">)</font> 

Range: <font size="6">[</font>*[Tex \LARGE -3,\infty]<font size="6">)</font>



{{{y=2x^2-3}}} Start with the given equation. 



{{{x=2y^2-3}}} Switch each "x" and "y". The goal is to now solve for "y"



{{{x+3=2y^2}}} Add 3 to both sides.



{{{(x+3)/2=y^2}}} Divide both sides by 2.



{{{y^2=(x+3)/2}}} Rearrange the equation



{{{y=sqrt((x+3)/2)}}} Take the square root of both sides. Note: since we made the domain <font size="6">[</font>*[Tex \LARGE 0,\infty]<font size="6">)</font>, this means that we're only dealing with the positive square root.



So the inverse equation is {{{y=sqrt((x+3)/2)}}} where the domain and range is simply flipped:


Domain: <font size="6">[</font>*[Tex \LARGE -3,\infty]<font size="6">)</font>

Range: <font size="6">[</font>*[Tex \LARGE 0,\infty]<font size="6">)</font>