MHB Simplify $A$: Multiply Fractions

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The expression for $A$ involves a product of fractions, each containing terms with integers and $\sqrt{2}$. The simplification process reveals that $A$ can be expressed in the form $P + Q\sqrt{2}$, where $P$ and $Q$ are coefficients to be determined. The calculations involve evaluating the numerator and denominator of each fraction, leading to a systematic approach for identifying $P$ and $Q$. Ultimately, the goal is to find the exact values of $P$ and $Q$ that satisfy the simplified expression. The final result will provide a clear representation of $A$ in its simplest form.
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$A=(\dfrac {1\times 4+\sqrt 2}{2\times 2-2})\times (\dfrac {2\times 5+\sqrt 2}{3\times 3-2})\times(\dfrac {3\times 6+\sqrt 2}{4\times 4-2})\times --------\times (\dfrac {2015\times 2018+\sqrt 2}{{2016}\times {2016}-2})$

please simplify $A$
 
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$$A=\prod_{n=1}^{2015}\dfrac{n(n+3)+\sqrt2}{(n+1)^2-2}=\prod_{n=1}^{2015}\dfrac{n^2+3n+\sqrt2}{n^2+2n-1}$$

$$=\prod_{n=1}^{2015}\dfrac{(n-(-1-\sqrt2))(n-(-2+\sqrt2)}{(n-(-1-\sqrt2))(n-(-1+\sqrt2))}=\prod_{n=1}^{2015}\dfrac{n+2-\sqrt2}{n+1-\sqrt2}$$

$$=\dfrac{3-\sqrt2}{2-\sqrt2}\cdot\dfrac{4-\sqrt2}{3-\sqrt2}\cdot\dfrac{5-\sqrt2}{4-\sqrt2}\dots=\dfrac{2017-\sqrt2}{2-\sqrt2}$$
 
greg1313 said:
$$A=\prod_{n=1}^{2015}\dfrac{n(n+3)+\sqrt2}{(n+1)^2-2}=\prod_{n=1}^{2015}\dfrac{n^2+3n+\sqrt2}{n^2+2n-1}$$

$$=\prod_{n=1}^{2015}\dfrac{(n-(-1-\sqrt2))(n-(-2+\sqrt2)}{(n-(-1-\sqrt2))(n-(-1+\sqrt2))}=\prod_{n=1}^{2015}\dfrac{n+2-\sqrt2}{n+1-\sqrt2}$$

$$=\dfrac{3-\sqrt2}{2-\sqrt2}\cdot\dfrac{4-\sqrt2}{3-\sqrt2}\cdot\dfrac{5-\sqrt2}{4-\sqrt2}\dots=\dfrac{2017-\sqrt2}{2-\sqrt2}$$
your answer is correct but not simlified yet
$A=P+Q\sqrt 2$
$P=? ,Q=?$
 
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$$P=2016,\quad\,Q=\dfrac{2015}{2}$$
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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