Question

If -1 and 1 are the zeroes of the polynomial f(x) = 3x3 – 2x2 + ax – b find the values of ‘a’ and ‘b’ ?

Answer 1

Answer:

It's not a quadratic equation..

Plz check ur question....

Answer 2

GiveN:

• 1 and -1 are two zeroes of the Polynomial x³ + 2x² + ax + b

To FinD:

• Values of a and b?

Step-by-Step Explanation:

-1 is a zero of the p(x). Then, p(-1) = 0

Replacing x with -1:

⇒ x³ + 2x² + ax + b = 0 (when x = -1)

⇒ (-1)³ + 2(-1)² + a(-1) + b = 0

⇒ -1 + 2 - a + b = 0

⇒ 1 - a + b = 0

⇒ a - b = 1 ------------(1)

1 is also a zero of p(x). Then p(1) = 0

Replacing x with 1:

⇒ x³ + 2x² + ax + b = 0

⇒ (1)³ + 2(1)² + a(1) + b = 0

⇒ 3 + a + b = 0

⇒ a + b = -3 --------(2)

Adding (1) and (2),

⇒ a - b + a + b = 1 - 3

⇒ 2a = -2

⇒ a = -1

Then,

⇒ -1 - b = 1

⇒ b = -2

Hence,

The required value of a and b is:

$\Large{ \boxed{ \sf{ \red{a = - 1 \: and \: b = - 2}}}}$