Find the value of a, if (x − a) is a factor of the polynomial (3x^3 + x^2 − ax − 81)

Question

KnowledgeBoat · Accepted Answer

Let, f(x) = 3x3 + x2 - ax - 81. Factor : ⇒ x - a = 0 ⇒ x = a. Since (x − a) is the factor, thus f(a) = 0. ⇒ 3(a)3 + a2 - a(a) - 81 = 0 ⇒ 3a3 + a2 - a2 - 81 = 0 ⇒ 3a3 - 81 = 0 ⇒ 3a3 = 81 ⇒ a3 = ⇒ a3 = 27 ⇒ a = ⇒ a = 3. Hence, the value of a = 3.

Mathematics

Find the value of a, if (x - a) is a factor of the polynomial 3x³ + x² - ax - 81.

Factorisation

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Mathematics

Find the value of a, if (x - a) is a factor of the polynomial 3x3 + x2 - ax - 81.

Factorisation

Related Questions

Using the factor theorem, show that (x - 2) is a factor of x3 + x2 - 4x - 4. Hence factorize the polynomial completely.

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If (x - 2) is a factor of 2x³ - x² - px - 2,
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