Suppose we have two quantities, $x$ and $y$, and we are given that $y$ may be expressed as an infinite power series in $x$:
$$ y = a_1 x + a_2x^2 + a_3x^3 + \cdots$$
You are given 6 balls, which appear to be identical except that 1 is white and 5 are black.
Q.744 Define $f(x) = \sum_{k=114}^{184} \frac{k}{x-k}$
Q.732 Let $L$ be the set of $n$ line segments with the property that three of them can be assembled to form a triangle.