Q174. What is the value of the infinite series: Σr=2∞ [ (1 + 2 + 3 + ... + (r − 1)) / r! ]?Mathematics — Sequences and Series — Question 174 of 208A. eB. 2eC. e/2D. 3e/2Practice more Mathematics MCQs for entrance exam preparation on Examora.io.← Previous Question Next Question →