Solve y=x²: Finding Values Where Function is Negative

To determine for which values of $x$ the function $y = x^2$ satisfies $f(x) < 0$, we need to analyze the nature of the quadratic function.

Step 1: Recognize the function $y = x^2$ is parabolic and opens upwards. For any real number $x$, $x^2$ is always non-negative, i.e., $x^2 \geq 0$.

Step 2: Since squaring any real number results in a value greater than or equal to zero, it is not possible for $x^2$ to be less than zero.

Conclusion: Therefore, there are no real values of $x$ for which $x^2 < 0$. The correct conclusion is that no $x$ satisfies $x^2 < 0$.