volume_mute
If x < 0, What Is x · (+∞)?
publish date: 2026/05/23 22:07:22.354840 UTC
volume_mute
If \(x < 0\) (a negative real number), what is \(x \cdot (+\infty)\)?
Correct Answer
\(-\infty\)
Explanation
When \(x < 0\): \(x \cdot (+\infty) = -\infty\). Multiplying an unboundedly large positive quantity by a negative number flips its sign, giving an unboundedly large negative quantity. Similarly, \(x \cdot (-\infty) = +\infty\) for \(x < 0\).
Reference
Introduction to Differential Calculus (Systematic Studies with Engineering Applications for Beginners) - 2012