- We know that e^(i*theta) = cos(theta) + i sin(theta)
- now, if theta = pi radians, then, we know that e^(i Pi) = cos(Pi) + i sin (Pi)
- Now, cos(Pi rad) = cos (180 deg) = -1, and sin(Pi) = 0
- so, e^(i Pi) = -1
- now, square on both sides, so we get:
- e^(2 i Pi) = 1
- now take ln on both sides, so as to get
- 2 i Pi = 0
clearly this is absurd, so something strange must be going on when taking a log of a complex number (step 7). and it turns out that yes, indeed this is a tricky situation, and this leads us to the topic of "Complex Logarithms". Essentially what is going on here is the following (as Wikipedia explains): A logarithm of a complex number essentially has "infinite" answers. (kind of like "aliasing"). Will revisit this page soon.
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