It's been a while since JPaul and I have had a class, so I tried to catch him up without going too quickly. Today we covered most of 1.5 on Powers of i. We went through the pattern of i^1, i^2, i^3, i^4, etc. JPaul recognized that after a while the terms begin to repeat. So we can use that pattern to determine large powers of i, like i^73. We would take the power, divide it by 4 and the remained becomes the new power. Since 73/4 is 18 with remainder 1, then i^73=i^1. Next we practiced adding and subtracting imaginary numbers. JPaul combined like terms, keeping the real parts separate from the imaginary parts. Tomorrow we will finish the section.