问题
选择题
已知x+y=10,xy=24,则x2+y2值是( )
A.52
B.76
C.100
D.148
答案
∵x+y=10,xy=24,
∴x2+y2=(x+y)2-2xy,
=100-48,
=52;
故选A.
已知x+y=10,xy=24,则x2+y2值是( )
A.52
B.76
C.100
D.148
∵x+y=10,xy=24,
∴x2+y2=(x+y)2-2xy,
=100-48,
=52;
故选A.