find the values of a and b so that ( x+1 ) and (x-1) are factors of
[tex] {x}^{4} \: + a {x}^{3} \: - 3 {x}^{2} \: + 2x \: + b \: [/tex]
class - 9
Share
Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
q(x) = x3 + 2x2 + a
Zeroes of q(x) are also the zeroes of p(x)
Þ q(x) is a factor of p(x)
To find the another factor of p(x), it should be divided by q(x).

x2 - 3x + 2 = (x – 2)(x – 1)
Therefore, 2 and 1 are the other zeroes of p(x).
Similarly, when p(x) is divided by x2 - 3x + 2, the quotient is x3 + 2x2 – 1 and the
Remainder is (b + 2).
x3 + 2x2 – 1 = x3 + 2x2 + a
⇒ a = -1
Remainder = 0
⇒ (b + 2) = 0
⇒ b = -2