Complex Numbers & Quadratic Equations · JEE Main previous year questions

2009 2 questions

1. Q22009 · 27 Apr 2009 · Shift 1

   If the roots of the equation $b{x}^2+cx+a=0$ are imaginary, then for all real values of $x$, the expression $3b^2{x}^2+6bcx+2c^2$ is :

   1. A.less than $4ab$
   2. B.greater than $-4ab$
   3. C.less than $-4ab$
   4. D.greater than $4ab$
   Show answer

   Answer: B

2. Q32009 · 27 Apr 2009 · Shift 1

   If $\left|z-\frac{4}{z}\right|=2$, then the maximum value of $|z|$ is equal to :

   1. A.$\sqrt{5}+1$
   2. B.$2$
   3. C.$2+\sqrt{2}$
   4. D.$\sqrt{3}+1$
   Show answer

   Answer: A