Question

Which of the following is a polynomial with roots: -sqrt of 5, sqrt of 5, and -3.
a. x^3 – 2x^2 – 3x + 6
b. x^3 + 3x^2 – 5x – 15
c. x^3 – 3x^2 – 5x + 15
d. x^3 + 2x^2 – 3x – 6

Answer 1

@Nurali you're the best :o

Answer 2

Thanks

Answer 3

Knowing the three roots, you can multiply the three factors and see what polynomial you get.

Answer 4

-sqrt of 5, sqrt of 5, and -3
(x+sqrt 5)(x-sqrt 5)(x+3)=0
http://www.wolframalpha.com/input/?i=%28x%2Bsqrt+5%29%28x-sqrt+5%29%28x%2B3%29%3D0

Answer 5

Is it B? @Nurali

Answer 6

Yes