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


A) (-4, 7)

B) (4,-7)

C) (4, 7)

D) (-4, -7)

Correct Answer:
A) (-4, 7)

Description for Correct answer:

Since, \( \Large 2+i\sqrt{3} \) is a root of equation \( \Large x^{2}+px+q=0 \) therefore, \( \Large 2-i\sqrt{3} \) will be other root. Now sum of the roots \( \Large 2+i\sqrt{3} \) + \( \Large 2-i\sqrt{3} \) = -P

=> 4 = -P

Product of roots \( \Large (2+i\sqrt{3}) \) \( \Large (2-i\sqrt{3}) \) = q,

=> 7 = -q.

Hence (p,q) = (-4, 7)


Part of solved Quadratic Equations questions and answers : >> Elementary Mathematics >> Quadratic Equations








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