Question

If one root of the equation x^2 + 3x + 9 =0 is 3+3sqrt3i/2 then fine the other root. ​

Answer 1

Answer:

-3/2

Step-by-step explanation:

2x^2-3x-9=0

2x^2-6x+3x-9=0

2x(x-3)+3(x-3)

x-3=0 and 2x+3=0

hence the roots are 3 and -3/2

hope this will help you.

Answer 2

Step-by-step explanation:

Given equation is

2x

3

−9x

2

+kx−13=0 where k∈R

Since, any odd degree equation with real coefficients has at least one real root.

So, real root exist.

Let α be the real root.

Since, 2+3i is a root of the equation. So, other root will be 2-3i. (Imaginary roots always occurs in conjugate pairs.)

Now, sum of roots 2+3i+2−3i+α=

2

9

⇒α=

2

1