Answer:
P(x) = x³ - 3x² - 5x + 15
Explanation:
∵ The roots of the polynomial are -√5 , √5 , 3
∴ The polynomial has 3 factors:
(x - √5) , (x + √5) , (x - 3)
∴ P(x) = (x - √5)(x + √5)(x - 3)
= (x² + √5x - √5x - 5)(x - 3)
= (x² - 5)(x - 3) = x³ - 3x² - 5x + 15
∴ P(x) = x³ - 3x² - 5x + 15