Question

已知x²+y²-6x+4y+13=0,则x的y次方的值?已知4x²+2y²-4x

Answer 1

x²+y²-6x+4y+13=0

x²-6x+9+y²+4y+4=0

(x-3)²+(y+2)²=0

∴x-3=0

y+2=0

∴x=3

y=-2

∴x的y次方=3的(-2)次方=1/9

4x²-4xy+y²+y²+6y+9=0

(2x-y)²+(y+3)²=0

2x-y=0

y+3=0

∴x=-3/2

y=-3

xy=-3/2×(-3)=9/2