Evaluate
\[
\frac{1}{1\cdot6}+\frac{1}{6\cdot11}+\frac{1}{11\cdot16}+\cdots
\]
for \(n\) terms.
Show Hint
Whenever the denominator is of the form
\[
(a)(a+k),
\]
use
\[
\boxed{
\frac1{a(a+k)}
=
\frac1k
\left(
\frac1a-\frac1{a+k}
\right)
}
\]
which usually produces a telescoping series.