KnowledgeBoat Logo
|

Mathematics

Find the value of a, if the division of ax3 + 9x2 + 4x - 10 by x + 3 leaves a remainder 5.

Factorisation

56 Likes

Answer

x + 3 = 0 ⇒ x = -3.

Given, when ax3 + 9x2 + 4x - 10 is divided by x + 3, the remainder is 5.

∴ On substituting x = -3 in ax3 + 9x2 + 4x - 10, remainder = 5.

⇒ a(-3)3 + 9(-3)2 + 4(-3) - 10 = 5

⇒ -27a + 81 - 12 - 10 = 5

⇒ -27a + 59 = 5

⇒ 27a = 59 - 5

⇒ 27a = 54

⇒ a = 5427\dfrac{54}{27} = 2

Hence, a = 2.

Answered By

34 Likes


Related Questions