an expression, the name of the variable (for
example n), and the bounds (for example a and b).
sum returns the discrete sum of this expression with respect to
the variable from a to b.
This result comes from the decomposition of
- = - = - - -
* = *() = *(1 + + )
* = *( + + )
After simplification by
, it remains :
- + *(1 + ) - + *( + ) = -
- for N = 10 the sum is equal to :
1/4 - 1/220 = 27/110
- for N = + the sum is equal to : 1/4 because
approaches zero when N approaches infinity.