Advanced Math practice question

Answer: -8

x⁴ = 16 gives x = ±2; since x < 0, x = −2, and x³ = −8.

Common wrong answers

If you answered 8

8 uses x = 2, which is not negative.

If you answered -4

−4 is x², with the wrong sign.

If you answered -64

−64 is (−4)³, taking x = −4.

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