Question

已知(x-2)2次方+(y-3)4次方=0.求3x—[(4x—2y)+2（4x—y）—3(2x+y)]的值 高分悬赏！ 急求答案！

Answer 1

(x-2)2次方+(y-3)4次方=0.
则必有：
x-2=0
y-3=0
解得：x=2；y=3
3x—[(4x—2y)+2（4x—y）—3(2x+y)]
=3x-4x+2y-8x+2y+6x+3y
=-3x+7y
=-3×2+7×3
=-6+21
=15

Answer 2

x-2=0,y-3=0
x=2,y=3
3x—[(4x—2y)+2（4x—y）—3(2x+y)]
=3x-(4x-2y+8x-2y-6x-3y)
=3x-(6x-7y)
=3x-6x+7y
=7y-3x
=7x3-3x2
=21-6
=15

Answer 3

已知(x-2)2次方+(y-3)4次方=0
(x-2)^2+(y-3)^4=0
因为两个整数相加为0，
所以(x-2)^2=0,(y-3)^4=0
得x-2=0,y-3=0
x=2,y=3
3x—[(4x—2y)+2（4x—y）—3(2x+y)]
化简=3x-[(4x-2y)+(8x-2y)-(6x+3y)]
=3x-(4x-2y+8x-2y-6x-3y)
=3x-4x+2y-8x+2y+6y+3y
=-3x+7y
把x=2,y=3带入原式得：-3x2+7x3=15
希望对你有所帮助，不懂可以追问。

Answer 4

(x-2)2次方+(y-3)4次方=0.
所以x=2,y=3
3x—[(4x—2y)+2（4x—y）—3(2x+y)]
=6-(8-6+10-21)
=15

Answer 5

(x-2)2次方+(y-3)4次方=0.
则必有：
x-2=0
y-3=0
解得：x=2；y=3
3x—[(4x—2y)+2（4x—y）—3(2x+y)]
=3x-4x+2y-8x+2y+6x+3y
=-3x+7y
=-3×2+7×3
=-6+21
=15

Answer 6

x=2 y=3
代入
3x2-(2+2x5-3x7)=15