若多项式2(x²-3xy-y²)-(x²+2mxy+2y²}中不含xy项,则m等于多少?

x���MN�0��R��Ǝ�81M����Hc�"$� ��vH�B�X�q
��z�.�{�F���Ld_�������[�q�������..�n��7�������l6�̦W��KY�����>��\�ޯm^�z��Xe<0�h���!/L�WFi7�!+�~3=8�{�n6���7���l
;Ij�|�g�

若多项式2(x²-3xy-y²)-(x²+2mxy+2y²}中不含xy项,则m等于多少?
若多项式2(x²-3xy-y²)-(x²+2mxy+2y²}中不含xy项,则m等于多少?

若多项式2(x²-3xy-y²)-(x²+2mxy+2y²}中不含xy项,则m等于多少?