若存在过点（1，0）的直线与曲线y=x3和 y=ax2+154x−9 都相切，则a等于

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若存在过点（1，0）的直线与曲线y=x³和 y=ax2+15

4

x−9 都相切，则a等于（）

A：﹣1或 $- \frac{25}{64}$

B：﹣1或 $\frac{21}{4}$

C： $- \frac{7}{4}$ 或 $- \frac{25}{64}$

D： $- \frac{7}{4}$ 或7

上一题下一题 0.0难度选择题更新时间:2019-06-12 04:00:13

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A

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