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ZX-14378BA6732024年10月北美B卷 · 第 22 题
2024年10月北美B卷 · 原库模块 2 · Q22 原库参考解析
\( f\left(x\right)=ax^2+3x+c \)
In the given quadratic function, a and c are constants. The graph of \( y=f\left(x\right) \) in the xy-plane is a parabola that opens upward and has a vertex at the point (h, k), where h and k are constants. If k < 0 and \( f\left(-7\right)=f\left(1\right) \), which of the following must be true?
Ⅰ. c < 0
Ⅱ. a ≥ 1
参考答案：
解题思路
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