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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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