Difficulty: Easy
Correct Answer: - 2
Explanation:
Introduction / Context:The original stem is garbled; applying the Recovery-First Policy, we interpret it minimally as finding the minimum value of x^2 + 1 − 3. This preserves the intended skill: identifying minima of a simple quadratic expression.
Given Data / Assumptions:
Concept / Approach:For any real x, x^2 ≥ 0. A quadratic of the form x^2 + k reaches its minimum when x = 0. Therefore, the least value occurs at the vertex of the parabola, here at x = 0.
Step-by-Step Solution:
Rewrite the expression: x^2 + 1 − 3 = x^2 − 2Since x^2 ≥ 0 for all real x, the minimum of x^2 is 0Thus, minimum of x^2 − 2 is 0 − 2 = −2Verification / Alternative check:Plug x = 0 into the expression: 0^2 − 2 = −2. For any nonzero x, x^2 > 0, so the value becomes greater than −2, confirming it is the minimum.
Why Other Options Are Wrong:−3 and −1 are values that cannot be achieved by x^2 − 2 since x^2 cannot be negative; 0 is achievable only if x^2 = 2, which is larger than the minimum.
Common Pitfalls:Missing the simplification to x^2 − 2 or thinking x^2 can be negative. Remember x^2 ≥ 0 for all real x.
Final Answer:− 2
Discussion & Comments