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The set of all real values of x for which $$(x^{2}-\mid x+9\mid+x)>0$$, is
We are asked to solve
$$x^2 - |x+9| + x > 0$$
Split into two cases based on the absolute value.
Case 1: $$x+9 \ge 0 \Rightarrow x \ge -9$$
$$|x+9| = x+9$$
Inequality becomes: $$x^2 - (x+9) + x > 0 \implies x^2 - 9 > 0 \implies (x-3)(x+3) > 0$$
So $$x<-3 or x>3$$. Combined with $$x\ge -9$$, we get $$x\in [-9,-3) \cup (3,\infty)$$
Case 2: $$x+9 < 0 \Rightarrow x < -9$$
$$|x+9| = -(x+9) = -x - 9$$
Inequality becomes: $$x^2 - (-x-9) + x > 0 \implies x^2 + 2x + 9 > 0$$
The quadratic $$x^2 + 2x + 9$$ has discriminant (4-36=-32 <0), so always positive. But in this case (x<-9), so inequality is satisfied. Thus (x < -9) also works.
$$x < -3 \text{or} x>3$$
So the solution set is $${(-\infty,-3) \cup (3,\infty)}$$
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