Unit Imaginary Number. The unit Imaginary Number (the equivalent of 1 for Real Numbers) is â(â1) (the square root of minus one). In mathematics we use i (for imaginary) but in electronics they use j (because i already means current, and the next letter after i is j). Examples of Imaginary Numbers i
8 Things You Must Do When Your Flight Is Cancelled Or Delayed. 1  Fly in the morning. You can almost stop reading here, this one is so key. 2  Avoid regional jets flying out of hub airports. Hub airports depriorize small regional planes because bumping them affects fewer passengers and costs airlines less money than rerouting an AirBus.
Expedia, for example, states that passengers may have the option to cancel for a refund but doesn't guarantee it. But if you're booking flights at the recommended 54 days before your trip, you're most likely in luck. The first flights you book don't have to be the ones you take. ...just take a price break instead. CORRECTION: A previous version of this post stated that airlines must either hold your flight for 24 hours after booking OR allow you to cancel for a full refund. In fact, they must do both.