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Let Z be the set of integers. If $$A = \{x \in Z : 2^{(x+2)(x^2-5x+6)} = 1\}$$ and $$B = \{x \in Z : -3 < 2x - 1 < 9\}$$, then the number of subsets of the set $$A \times B$$, is:
We have the set $$A=\{x\in \mathbb Z:2^{(x+2)\bigl(x^{2}-5x+6\bigr)}=1\}.$$
First, recall the basic fact: for any real number $$k,$$ the equality $$2^{k}=1$$ holds only when $$k=0,$$ because the base $$2$$ is positive and not equal to $$1.$$ Hence, to find all integers $$x$$ belonging to $$A,$$ we must force the exponent to be zero:
$$ (x+2)\bigl(x^{2}-5x+6\bigr)=0. $$
This product equals zero precisely when at least one factor is zero. We split it:
1. $$x+2=0 \;\Longrightarrow\; x=-2.$$
2. $$x^{2}-5x+6=0.$$
We factor the quadratic:
$$ x^{2}-5x+6=(x-2)(x-3). $$
So
$$ (x-2)(x-3)=0 \;\Longrightarrow\; x=2 \text{ or } x=3. $$
Collecting all integer solutions, we obtain
$$ A=\{-2,\,2,\,3\}, $$
which contains $$|A|=3$$ elements.
Now consider the set $$B=\{x\in\mathbb Z:-3<2x-1<9\}.$$ We solve the double inequality step by step.
First, add $$1$$ to every part:
$$ -3+1 < 2x-1+1 < 9+1 \;\Longrightarrow\; -2 < 2x < 10. $$
Next, divide every part by $$2$$ (the sign of $$2$$ is positive, so the inequalities keep their direction):
$$ \frac{-2}{2} < x < \frac{10}{2} \;\Longrightarrow\; -1 < x < 5. $$
The integers strictly between $$-1$$ and $$5$$ are
$$ 0,\;1,\;2,\;3,\;4. $$
Thus
$$ B=\{0,\,1,\,2,\,3,\,4\}, $$
with $$|B|=5$$ elements.
We now form the Cartesian product $$A\times B=\{(a,b):a\in A,\;b\in B\}.$$ The counting principle tells us that
$$ |A\times B|=|A|\times|B|=3\times5=15. $$
Finally, the total number of subsets of any finite set containing $$n$$ elements is given by the formula $$2^{n}.$$ Substituting $$n=15,$$ we get
$$ \text{Number of subsets}=2^{15}. $$
Hence, the correct answer is Option D.
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