相等的；
|（a+bi）^2|
=|a^2-b^2+2abi|
=[(a^2-b^2)^2+(2ab)^2]^(1/2)
=[(a^4+b^4-2a^2b^2)+4a^2b^2]^(1/2)
=[(a^2+b^2)^(2)]^(1/2)
=a^2+b^2
=|a+bi|^2