KnowledgeBoat Logo
|

Mathematics

The polynomial x2 + x + b has (x + 3) as a factor of it.

Statement 1: The value of b is -4.

Statement 2: (x + 3) is a factor of x2 + x + b ⇒ (3)2 + 3 + b = 0.

option

  1. Both the statements are true.

  2. Both the statements are false.

  3. Statement 1 is true, and statement 2 is false.

  4. Statement 1 is false, and statement 2 is true.

Factorisation

1 Like

Answer

Both the statements are false.

Reason

By factor theorem,

(x - a) is a factor of the polynomial f(x), if the remainder i.e. f(a) = 0.

⇒ x + 3 = 0

⇒ x = -3

Let, f(x) = x2 + x + b

Given,

The polynomial x2 + x + b has (x + 3) as a factor of it.

⇒ (-3)2 + (-3) + b = 0

⇒ 9 - 3 + b = 0

⇒ 6 + b = 0

⇒ b = -6.

∴ Statement 1 is incorrect.

Since,

⇒ (-3)2 + (-3) + b = 0

∴ Statement 2 is incorrect.

Hence, option 2 is the correct option.

Answered By

2 Likes


Related Questions