Answer:
n = - 3
Explanation:
if (x - a) is a factor of a polynomial f(x) , then the remainder on division by (x - a) is zero and f(a) = 0
given (x - 1) is a factor of the polynomial , then substitute x = 1 and equate to zero, that is
(1)³ - 3(1)² + 5(1) + n = 0
1 - 3(1) + 5 + n = 0
1 - 3 + 5 + n = 0
3 + n = 0 ( subtract 3 from both sides )
n = - 3