问题
填空题
已知a=
|
答案
∵a=
=2+1 2- 3
,b=3
=2-1 2+ 3
,3
∴a2-3ab+b2=(a-b)2-ab,
=(2+
-2+3
)2-(2+3
)(2-3
),3
=(2
)2-(4-3),3
=12-1,
=11.
故答案为:11.
已知a=
|
∵a=
=2+1 2- 3
,b=3
=2-1 2+ 3
,3
∴a2-3ab+b2=(a-b)2-ab,
=(2+
-2+3
)2-(2+3
)(2-3
),3
=(2
)2-(4-3),3
=12-1,
=11.
故答案为:11.