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If the numbers appeared on the two throws of a fair six faced die are $$\alpha$$ and $$\beta$$, then the probability that $$x^2 + \alpha x + \beta > 0$$, for all $$x \in \mathbb{R}$$, is
Given quadratic expression
$$x^2+\alpha x+\beta$$
For
$$x^2+\alpha x+\beta>0\quad \forall x\in\mathbb R,$$
the quadratic must have a positive leading coefficient and no real roots.
Since the coefficient of $$x^2$$ is already positive, we only require
$$\Delta<0$$
Therefore,
$$\alpha^2-4\beta<0$$
$$\alpha^2<4\beta$$
Now,
$$\alpha,\beta\in\{1,2,3,4,5,6\}$$
We count favorable cases.
For $$\alpha=1,$$
$$1<4\beta$$
which is true for all
$$\beta=1,2,3,4,5,6$$
Hence,
$$6$$ cases.
For $$\alpha=2,$$
$$4<4\beta$$
$$\beta>1$$
Hence,
$$\beta=2,3,4,5,6$$
giving
$$5$$ cases.
For $$\alpha=3,$$
$$9<4\beta$$
$$\beta\ge3$$
Hence,
$$4$$ cases.
For $$\alpha=4,$$
$$16<4\beta$$
$$\beta>4$$
Hence,
$$\beta=5,6$$
giving
$$2$$ cases.
For $$\alpha=5,$$
$$25<4\beta$$
is impossible.
Hence,
$$0$$ cases.
For $$\alpha=6,$$
$$36<4\beta$$
is impossible.
Hence,
$$0$$ cases.
Therefore, total favorable outcomes are
$$6+5+4+2=17$$
Total possible outcomes are
$$6\times6=36$$
Hence, the required probability is
$$\boxed{\frac{17}{36}}$$
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