A convex expression can be multiplied by a nonnegative constant, and the resulting expression will be convex. When a convex expression is multiplied by a non-real (complex) constant, the resulting expression is neither convex nor concave.
A convex expression can be multiplied by a nonnegative constant, and the resulting expression will be convex. When a convex expression is multiplied by a non-real (complex) constant, the resulting expression is neither convex nor concave.