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If x, y, z are the three factors of a³ - 7a - 6, then value of x + y + z will be?

13a
23
36
4a

Answer:- 1

Explanation:-

Solution:

\begin{aligned} a^{3} - 7 a - 6 \\ (a + 1) (a^{3} - a - 6) \\ (a + 1) (a + 2) (a - 3) \\ Now, Sum of factors \\ (a + 1) + a + 2 + a - 3 = 3 a \end{aligned}

$\eqalign{ & {a^3} - 7a - 6 \cr & \left( {a + 1} \right)\left( {{a^3} - a - 6} \right) \cr & \left( {a + 1} \right)\left( {a + 2} \right)\left( {a - 3} \right) \cr & {\text{Now}},{\text{Sum of factors}} \cr & \left( {a + 1} \right) + a + 2 + a - 3 = 3a \cr}$

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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} a^{3} - 7 a - 6 \\ (a + 1) (a^{3} - a - 6) \\ (a + 1) (a + 2) (a - 3) \\ Now, Sum of factors \\ (a + 1) + a + 2 + a - 3 = 3 a \end{aligned}

$\eqalign{ & {a^3} - 7a - 6 \cr & \left( {a + 1} \right)\left( {{a^3} - a - 6} \right) \cr & \left( {a + 1} \right)\left( {a + 2} \right)\left( {a - 3} \right) \cr & {\text{Now}},{\text{Sum of factors}} \cr & \left( {a + 1} \right) + a + 2 + a - 3 = 3a \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM" } }

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