Q. If $2 + i\sqrt{3}$ is a root of the equation $x^{2} + px + q = 0,$ where $p$ and $q$ are real, then $(p,q)$ is equal to

A) $( - 4,\ 7)$
B) $(4,\ - 7)$
C) $(4,\ 7)$
D) $( - 4,\ - 7)$
Explanation

(a)
Since, $2 + i\sqrt{3}$ is a root of equation $x^{2} + px + q = 0$. Therefore, $2 - i\sqrt{3}$ will be other root.
Now, Sum of the roots $= \left( 2 + i\sqrt{3} \right) + (2 - i\sqrt{3}$ )$= - p$
$\Rightarrow 4 = - p$
Product of roots $= \left( 2 + i\sqrt{3} \right) + (2 - i\sqrt{3}) = q$
$\Rightarrow 7 = q$
Hence, $(p,q) = ( - 4,\ 7)$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.