Answer:
Step-by-step explanation:
The function f(z) is conformal at z0 if there is an angle φ and a scale a > 0 such that for any smooth curve γ(t) through z0 the map f rotates the tangent vector at z0 by φ and scales it by a. That is, for any γ, the tangent vector (f ◦ γ)/(t0) is found by rotating γ/(t0) by φ and scaling it by a.
