来自金树山的问题
已知:x+y+z=1,x2+y2+z2=2,x3+y3+z3=3,试求:(1)xyz的值;(2)x4+y4+z4的值.
已知:x+y+z=1,x2+y2+z2=2,x3+y3+z3=3,试求:
(1)xyz的值;
(2)x4+y4+z4的值.
1回答
2020-02-13 08:07
已知:x+y+z=1,x2+y2+z2=2,x3+y3+z3=3,试求:(1)xyz的值;(2)x4+y4+z4的值.
已知:x+y+z=1,x2+y2+z2=2,x3+y3+z3=3,试求:
(1)xyz的值;
(2)x4+y4+z4的值.
(1)由条件可得(x+y+z)2=x2+y2+z2+2(xy+yz+xz)=1,
即1=2+2(xy+yz+xz),∴xy+yz+xz=-12