The function f (x) = x ^ 2 + ax + 3 when a belongs to [- 2,2], f (x) > = a is constant, and the value range of X is obtained~

The function f (x) = x ^ 2 + ax + 3 when a belongs to [- 2,2], f (x) > = a is constant, and the value range of X is obtained~

This parabola opens upward, so the lowest point is on the central axis, and the central axis is just x = - A / 2, so when a = ± 2, f (x) gets the minimum value, which is 2. That is to say, when a belongs to [- 2,2], f (x) is always greater than or equal to A. substituting x = - A / 2, the value range of X is [- 1,1]

Elden Ring Premiere

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