1990 AMC 12 Problem 2

Attempt Problem 2 of the 1990 AMC 12 below, then check your answer against the professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 1990 AMC 12 solutions, or check the answer key.

All problems are used with official legal permission of the Mathematical Association of America (MAA).

2.

(14)−14=\left(\dfrac14\right)^{-\frac{1}{4}}=
−16-16
−2-\sqrt2
−116-\frac1{16}
1256\frac1{256}
2\sqrt2
Answer: E
Concepts:fractional exponentnegative exponent
Small hint:
A negative exponent takes the reciprocal
Big hint:
Rewrite 44 as a power of 22
Solution:
Taking the reciprocal gives 414=(22)14=212=2.4^{\frac{1}{4}}=(2^2)^{\frac{1}{4}}=2^{\frac{1}{2}}=\sqrt2.
Thus the correct answer is E.
LIVE by Po-Shen Loh
Programs

LIVE Classes

Self-Paced Classes

Stars

Scholarship

About Us

Who Is Po-Shen Loh?

Email Contact

Newsletter

Jobs

Become a Star

For a more Thought Full world.

© 2026 Expii, Inc.