Edge Cases Math Example 4

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Example 4

medium
Test the edge cases n=0n=0 and n=1n=1 for the formula k=1nk=n(n+1)2\sum_{k=1}^{n} k = \frac{n(n+1)}{2}.

Solution

  1. 1
    For n=1n=1: LHS =1= 1. RHS =122=1= \frac{1 \cdot 2}{2} = 1. Match.
  2. 2
    For n=0n=0: An empty sum (no terms) equals 0. RHS =012=0= \frac{0 \cdot 1}{2} = 0. Match.
  3. 3
    Both edge cases are handled correctly by the formula.

Answer

Formula valid for n=0 and n=1\text{Formula valid for } n=0\text{ and }n=1
Edge cases for summation formulas include n=0n=0 (empty sum) and n=1n=1 (single term). A robust formula should handle all boundary values correctly.

About Edge Cases

Special or extreme input values — such as zero, infinity, empty sets, or boundary conditions — where formulas or reasoning may behave differently.

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