y(x+y)+(x-y)²-(x+y)(x-y),其中x=-1/3,y=3

来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/22 21:30:21
y(x+y)+(x-y)²-(x+y)(x-y),其中x=-1/3,y=3y(x+y)+(x-y)²-(x+y)(x-y),其中x=-1/3,y=3y(x+y)+(x-y)

y(x+y)+(x-y)²-(x+y)(x-y),其中x=-1/3,y=3
y(x+y)+(x-y)²-(x+y)(x-y),其中x=-1/3,y=3

y(x+y)+(x-y)²-(x+y)(x-y),其中x=-1/3,y=3
y(x+y)+(x-y)²-(x+y)(x-y)
=xy+y²+x²-2xy + y² -x²+y²
= 3y²-xy
= 3×3²-(-1/3)×3
= 27 +1 = 28