问题
填空题
-3x2+6xy-(______ )=-(______ )2.
答案
-3x2+6xy-(x2+
y2)=-(4x2-6xy+9 4
y2)=-(2x-9 4
y)2,3 2
故答案为:x2+
y2,2x-9 4
y.3 2
-3x2+6xy-(______ )=-(______ )2.
-3x2+6xy-(x2+
y2)=-(4x2-6xy+9 4
y2)=-(2x-9 4
y)2,3 2
故答案为:x2+
y2,2x-9 4
y.3 2