Advanced Math practice question

Answer: -2 or −2

(−2)³ = −2 × −2 × −2 = −8, so x = −2. A cube of a negative number is negative, and there is exactly one real cube root.

Common wrong answers

If you answered 2

2³ = 8, not −8. The cube root of a negative number is negative.

If you answered -4

−4 is −8/2, halving instead of taking the cube root.

If you answered -512

−512 is (−8)³, cubing again instead of taking the root.

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