Given that f (x) = 1 / root x 2 + ax + A-1 is defined as (- ∞, 1-A) ∪ (- 1, + ∞), the value range of a is obtained

Given that f (x) = 1 / root x 2 + ax + A-1 is defined as (- ∞, 1-A) ∪ (- 1, + ∞), the value range of a is obtained

Because f (x) = 1 / radical x2 + ax + A-1,
So x2 + ax + A-1 > 0,
The factorization is: (x + 1) [x + (A-1)] > 0,
The corresponding equations are: - 1 and 1-A
The domain of function definition is (- ∞, 1-A) ∪ (- 1, + ∞)
Then 1-A = 2

Given that the definition field of a-ax + x ^ 2 under the function f (x) = root sign is r, the value range of a is obtained

Let g (x) = a-ax + x ^ 2, then G (x) ≥ 0, so the parabola opening of G (x) is upward and there is no or one intersection point on X axis, then Δ = a ^ 2-4a ≤ 0, (A-4) a ≤ 0, so 0 ≤ a ≤ 4