Magdalena’s Reviews > Thinking Better: The Art of the Shortcut > Status Update

*Logarithm= shortcut to multiplication (as a sumarion instead) - fascinating. As is the other example AxB as a difference of squares of (A+B)&(A-B), althought I've seen a similar idea to the second before as AxB = ((C-X)(C+X) for close numbers it's easy.
*Imaginary numbers: intuitive concept, but I've never thought about them not actually following the same rules of algebra. It's so smart to think of verifying that.