- Thread starter
- #1

\(\displaystyle

\sum_{i=2}^{99}((i + 1)^2 - i^2))\)

So I found the pattern and got

\(\displaystyle

((3^2) - 2^2)) + ((4)^2 - (3)^2)) + ((5^2) - (4)^2)\) ... etc etc

\(\displaystyle 100^2 -2^2 = 9,996?\) Is this correct?

#2 Evaluate the sum

\(\displaystyle

\sum_{i=2}^{100}(i^2 -(i - 2)^2) \)

and got: \(\displaystyle 100^2 + 99^2 - 1 = 19,800\). Is this correct?