Question

Which of the following is a polynomial with roots -√5 ,√5 , and 3 ?

answers
x3 - 2x2 - 3x + 6
x3 + 2x2 - 3x - 6
x3 - 3x2 - 5x + 15
x3 + 3x2 - 5x - 15

Answer 1

third option

Answer 2

x^3 - 3x^2 - 5x + 15=0

See graph at:

http://www.wolframalpha.com/input/?i=x%5E3+-+3x%5E2+-+5x+%2B+15%3D0

Answer 3

@ skate -->Questions?

Answer 4

x = - sqrt 5
x = sqrt 5
x = 3

(x+sqrt 5)(x-sqrt 5)(x-3)
(x^2-5)(x-3)
x^3 - 3x^2 - 5x + 15

Answer 5

^that's how you'll know