By Deepa Seetharaman SAN FRANCISCO (Reuters) – Amazon.com Inc posted a much larger-than-expected loss in the second quarter as its rapid pace of investment in businesses such as digital content and consumer electronics offset a 23 percent jump in revenue. Shares of Amazon have slid 10 percent so far in 2014, as investors grow increasingly leery of betting on potentially rapid long-term growth at the expense of little to no profit. Amazon has invested heavily in several new business lines, from a subscription book service and digital video content to a TV streaming-box and an upcoming Fire smartphone.