已知a+b=7,ab=5,则a 2 +b 2 =______

已知a+b=7,ab=5,则a 2 +b 2 =______.
2025-02-24 14:31:08
推荐回答(1个)
回答1:

∵a+b=7,ab=5,
∴a 2 +2ab+b 2 =49,
即a 2 +2×5+b 2 =49,
解得a 2 +b 2 =49-10=39.
故答案为:39.