Complex Numbers And Quadratic Equations question 730
Question: If a root of the equation $ x^{2}+px+12=0 $ is 4, while the roots of the equation $ x^{2}+px+q=0 $ are same, then the value of $ q $ will be [RPET 1991; AIEEE 2004]
Options:
A) 4
B) 4/49
C) 49/4
D) None of these
Show Answer
Answer:
Correct Answer: C
Solution:
Put $ x=4 $ in $ x^{2}+px+12=0 $ , we get $ p=-7 $ Now second equation $ x^{2}+px+q=0 $ have equal roots. Therefore $ p^{2}=4q\Rightarrow q=\frac{49}{4} $
BETA
