2015 AMC 10B Problem 1

Below is the professionally curated solution for Problem 1 of the 2015 AMC 10B, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2015 AMC 10B solutions, or check the answer key.

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Concepts:exponentorder of operations

Difficulty rating: 560

1.

What is the value of 2(2)2?2-(-2)^{-2}?

2 -2

116 \dfrac{1}{16}

74 \dfrac{7}{4}

94 \dfrac{9}{4}

6 6

Solution:

Since (2)2=1(2)2=14(-2)^{-2}=\frac{1}{(-2)^2}=\frac14, the expression is 214=74.2-\frac14=\frac74.

Thus, the correct answer is C.

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