Question 892311
It has an inverse however it is not a function.
If you interchange x and y and solve for the new y (the inverse), you get,
{{{x=y^2}}}
{{{y=0 +- sqrt(x)}}}
Since you have the plus/minus in front of the {{{sqrt(x)}}}, you have two {{{y}}} values for every {{{x}}} value, which violates the definition of a function. 
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The original function
{{{graph(300,300,-5,5,-5,5,x^2)}}}
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The original function and its inverse
{{{graph(300,300,-5,5,-5,5,x^2,sqrt(x),-sqrt(x))}}}