2. \( -\sqrt[3]{81} \)

Did you know that the cube root of a number is asking the question: which number multiplied by itself three times gives us that number? For \( -\sqrt[3]{81} \), we can break it down to find that \( \sqrt[3]{81} = 4.326 \) approximately, so when we take the negative, we get about \( -4.326 \). It's like asking for the 'bad boy' version of that number! Now, let’s get practical! Negative cube roots can show up in various real-world applications, particularly in physics and engineering. For instance, when calculating forces in opposing directions, understanding how negatives operate can be crucial. So next time you face a negative cube root, remember, it’s just another twist in the mathematical adventure!