问题
填空题
若a+b=5,ab=6,求:①a2+b2 =________;②a4+b4 =________的值.
答案
13,97
a2+b2 =(a+b)2-2 ab=13;a4+b4 =(a2+b2 )2-2 a2 b2=97.
若a+b=5,ab=6,求:①a2+b2 =________;②a4+b4 =________的值.
13,97
a2+b2 =(a+b)2-2 ab=13;a4+b4 =(a2+b2 )2-2 a2 b2=97.