2.4. VISUALIZING COMPLEX FUNCTIONS
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2.3.2 EXERCISES
2.3. Sketch the following lines and circles and their images under the given mapping f.
(a) z(t) = 1 + it, t in R, f(z) = iz.
(b) iz - i/√3(z) = 2, f(z) = (-2√3 + 2i)z - 2 - i.
(c) z(t) = -2 - 2i + 4e^(it), 0 <= t < 2π, f(z) = -z - 2.
2.4. What is the center and radius of the circle obtained by mapping the line (3 + 4i)z + (3 - 4i)z = 4 by the inversion f(z) = 1/z? [Hint: Put the line formula in standard form first by scaling so that |A| = 1.]
2.5. What is the distance to the origin and the normal to the line obtained by mapping the circle z/√(z) - (2 + 3i)z - (2 - 3i)/√(z) = 0 by the inversion f(z) = 1/z?
2.6. Show that the effect of inversion by f(z) = 1/z on stereographic projection is a reflection across the y = 0 plane and across the z = 0 plane for points on the Riemann sphere. That is, if z is stereographically projected to A = (x, Y, Z) on the Riemann sphere, then w = 1/z is stereographically projected to B = (x, -Y, -Z). [Hint: Use the result of Exercise 1.23.]