I am trying to figure out the following problem:
Find an upper bound on |z3-2z2+6z+2| defined by |z|<2.
I've done the following:
= √(x3-3xy2-2x2+2y2+6x+2)2+ (3x2y-y3-4xy+6y)2
I don't think I'm going this the right way. Any ideas? Should I not change to x+iy form?