## Precalculus: Mathematics for Calculus, 7th Edition

$\dfrac {1}{3}-\dfrac {1}{2}\neq \dfrac {1}{4}-\dfrac {1}{3}\neq \dfrac {1}{5}-\dfrac {1}{4}\Rightarrow \dfrac {1}{2},\dfrac {1}{3},\dfrac {1}{4},\dfrac {1}{5}\ldots$is not an arithmetic sequence becouse difference between terms is not equal