Question

Find the values of 'a' and 'b', so that the polynomial x3 − ax2 − 13x + b has (x−1) and (x+3) as factors:

Q: Answer-Find the values of 'a' and 'b', so that the polynomial x3 − ax2 − 13x + b has (x−1) and (x+3) as fac...

Let px x3 ax2 13x b If x - 1 and x 3 are factors of px, then p l O and p - 3 O 13 a12 13 x 1 b 0 and 33 a32 133 b 0 1 a 13 b 0 and 27 9a 39 b 0 a b - 12 ..1 and 9a b 12 ..2 Subtracting the equation from first, we get a - b - 9a - b - 12 - 12 - 8a - 24 a 3 Putting a 3 in a - b -12, We get, b 15