已知:x+y=-½,x-y=-7/2,求x-2(1/4x-1/3y²)+(-3/2x+1/3y²)的值

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已知:x+y=-½,x-y=-7/2,求x-2(1/4x-1/3y²)+(-3/2x+1/3y²)的值
已知:x+y=-½,x-y=-7/2,求x-2(1/4x-1/3y²)+(-3/2x+1/3y²)的值

已知:x+y=-½,x-y=-7/2,求x-2(1/4x-1/3y²)+(-3/2x+1/3y²)的值
x=-2 y=3/2
∴原式=x-1/2x+2/3y^2-3/2x+1/3y^2=-x+y^2=2+9/4=4.25

先将待求表达式化简,然后代入x y的值即可!