已知m2+2mn=384,3mn+2n2=560,那么2m2+13mn+6n2-444的值是 _.
问题描述:
已知m2+2mn=384,3mn+2n2=560,那么2m2+13mn+6n2-444的值是 ______.
答
∵2m2+13mn+6n2-444
=2m2+4mn+9mn+6n2-444
=2(m2+2mn)+3(3mn+2n2)
而m2+2mn=384,3mn+2n2=560,
∴2m2+13mn+6n2-444
=2×384+3×560-444
=2004.
故答案为:2004.