For the geometric series ∑n=0∞rn\sum_{n=0}^{\infty} r^n∑n=0∞rn, which condition ensures the series sum equals 11−r\frac{1}{1-r}1−r1?
r>1r > 1r>1
∣r∣<1|r| < 1∣r∣<1
r≥1r \geq 1r≥1
r=0r = 0r=0 only