已知集合A={x|y=根号下x+1}，集合B={y|y=-x2+4x}，则A交B=

Question

如题所述

Answer 1

x ≥ -1-x�0�5 + 4x = -(x�0�5 - 4x + 4 - 4) = -(x - 2)�0�5 + 4即y ≤ 4故 A∩B = [-1，4]