$\"\"$

The equation is $\"\"$ .

Solve the above equation for $\"\"$ .

$\"\"$

Multiply each side by $\"\"$ .

$\"\"$

Compare with quadratic form $\"\"$ .

Roots are $\"\"$

In this case $\"\"$ .

Roots are $\"\"$

$\"\"$

$\"\"$ .

For any input of $\"\"$ , to get two outputs for $\"\"$ .

So, the equation $\"\"$ does not defines $\"\"$ as a function of $\"\"$ .

$\"\"$

The equation $\"\"$ is not a function.