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If x = 2, y = 1 and z = -3, then x³ + y³ + z³ - 3xyz is equal to?

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Answer:- 1

Explanation:-

Solution:

\begin{aligned} According to the question, \\ x = 2, y = 1, z = - 3 \\ x^{3} + y^{3} + z^{3} - 3 x y z = ? \\ As we know that \\ a + b + c = 0 then a^{3} + b^{3} + c^{3} - 3 a b c = 0 \\ 2 + 1 - 3 = 0 \\ ∴ x^{3} + y^{3} + z^{3} - 3 x y z = 0 \end{aligned}

$\eqalign{ & {\text{According to the question,}} \cr & x = 2,{\text{ }}y = 1,{\text{ }}z = - 3 \cr & {x^3} + {y^3} + {z^3} - 3xyz = ? \cr & {\text{As we know that}} \cr & a + b + c = 0{\text{ then }}{a^3} + {b^3} + {c^3} - 3abc = 0 \cr & 2 + 1 - 3 = 0 \cr & \therefore {x^3} + {y^3} + {z^3} - 3xyz = 0 \cr}$

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", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

\begin{aligned} According to the question, \\ x = 2, y = 1, z = - 3 \\ x^{3} + y^{3} + z^{3} - 3 x y z = ? \\ As we know that \\ a + b + c = 0 then a^{3} + b^{3} + c^{3} - 3 a b c = 0 \\ 2 + 1 - 3 = 0 \\ ∴ x^{3} + y^{3} + z^{3} - 3 x y z = 0 \end{aligned}

$\eqalign{ & {\text{According to the question,}} \cr & x = 2,{\text{ }}y = 1,{\text{ }}z = - 3 \cr & {x^3} + {y^3} + {z^3} - 3xyz = ? \cr & {\text{As we know that}} \cr & a + b + c = 0{\text{ then }}{a^3} + {b^3} + {c^3} - 3abc = 0 \cr & 2 + 1 - 3 = 0 \cr & \therefore {x^3} + {y^3} + {z^3} - 3xyz = 0 \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM" } }

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