Question

If [x-3) is a factor of the
polynomial (2x² + x + k), find k.​

Answer 1

If x - 3 is the factor of polynomial then when we put x as 3 then it will give 0 as resultant.

( 2x² + x + k ) = 0

2 × ( 3 )² + 3 + k = 0

2 × 9 + 3 + k = 0

18 + 3 + k = 0

21 + k = 0

k = - 21