Difficulty: Easy
Correct Answer: 1096
Explanation:
Introduction / Context:Recognizing algebraic identities is crucial for simplification. Here the numerator is a sum of cubes, and the denominator is the quadratic factor associated with that identity.
Given Data / Assumptions:
Concept / Approach:Use the identity a^3 + b^3 = (a + b)(a^2 − ab + b^2). Dividing by (a^2 − ab + b^2) cancels that factor, leaving just (a + b).
Step-by-Step Solution:
Apply identity: (a^3 + b^3) / (a^2 − ab + b^2) = a + b.Compute a + b = 725 + 371 = 1096.Verification / Alternative check:Multiplying back: (a + b)(a^2 − ab + b^2) reconstructs a^3 + b^3, confirming the correctness.
Why Other Options Are Wrong:9610, 1960, 1016, and 1090 are distractors derived from mis-adding or misordering digits; none equal 725 + 371.
Common Pitfalls:Using the difference-of-cubes formula incorrectly, or trying to expand cubes numerically instead of leveraging the identity.
Final Answer:1096
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