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    If x1/3+y1/3−z1/3x^{1/3} + y^{1/3} - z^{1/3}x1/3+y1/3−z1/3​ = 0, then find the value of (x+y-z)³ + 27 xyz.
    Question

    If x1/3+y1/3z1/3x^{1/3} + y^{1/3} - z^{1/3}​ = 0, then find the value of (x+y-z)³ + 27 xyz.

    A.

    -z³

    B.

    0

    C.

    1

    D.

    x³ + y³ - z²

    Correct option is B

    Given:

    x1/3+y1/3z1/3=0x^{1/3} + y^{1/3} - z^{1/3} = 0​​

    Solution:

    Rearranging the equation, we get:

    x1/3+y1/3=z1/3x^{1/3} + y^{1/3} = z^{1/3}​​

    Cubing both sides, we get:

    (x1/3+y1/3)3=(z1/3)3(x^{1/3} + y^{1/3})^3 = (z^{1/3})^3​​

    x+y+3(x1/3)(y1/3)(x1/3+y1/3)=zx + y + 3(x^{1/3})(y^{1/3})(x^{1/3} + y^{1/3}) = z​​

    Substituting x1/3+y1/3=z1/3x^{1/3} + y^{1/3} = z^{1/3}​, we simplify to:

    x+y+3(xyz)1/3=zx + y + 3(xyz)^{1/3} = z​​

    Rearranging the equation:

    x+yz=3(xyz)1/3x + y - z = -3(xyz)^{1/3}​​

    Now, cubing both sides, we get:

    (x+yz)3=(3(xyz)1/3)3 (x+yz)3=27xyz Thus,(x+yz)3+27xyz=27xyz+27xyz=0.(x + y - z)^3 = (-3(xyz)^{1/3})^3\\\ \\(x + y - z)^3 = -27xyz\\\ \\Thus, (x + y - z)^3 + 27xyz = -27xyz + 27xyz = 0 .​​

    Hence, the value of (x+yz)3+27xyz=0 (x + y - z)^3 + 27xyz = 0​.

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