x²+y²-2x-6y+10=0,求4(x²+y)(x²-y)-(2x²-y)&_其他解答

x²+y²-2x-6y+10=0,求4(x²+y)(x²-y)-(2x²-y)²

人气：166 ℃　时间：2019-10-20 00:02:08

解答

(x²-2x+1)+(y²-6y+9)=0(x-1)²+(y-3)²=0所以x-1=0,y-3=0x=1,y=3所以原式=4x⁴-4y²-4x⁴+4x²y-y²=4x²y-5y²=4*1*3-5*9=-33