已知a+b=5,ab=6,则a 2 +b 2 =______,a-b=______

已知a+b=5,ab=6,则a 2 +b 2 =______,a-b=______.
2025-12-13 04:16:38
推荐回答(1个)
回答1:

∵a+b=5,
∴(a+b) 2 =25,
即a 2 +2ab+b 2 =25,
∵ab=6,
∴a 2 +b 2 =25-2×6=25-12=13;
∵(a-b) 2 =a 2 -2ab+b 2 =13-2×6=13-12=1,
∴a-b=±1.
故答案为:13,±1.