Q43 / 125 · BITSAT 2015 · Mathematics
The root of the equation
$2(1+i) x^{2}-4(2-i) x-5-3 i=0$ which has
greater modulus is
- Correct answerA$\frac{3-5 i}{2}$
- B$\frac{5-3 \mathrm{i}}{2}$
- C$\frac{3-i}{2}$
- Dnone
Solution
$\begin{aligned} \text { Roots } &=\frac{4(2-i) \pm \sqrt{16(2-i)^{2}+8(1+i)(5+3 i)}}{4(1+i)} \\ &=\frac{4-i}{1+i} \text { or } \frac{-i}{1+i}=\frac{3-5 i}{2} \text { or } \frac{-1-i}{2} \end{aligned}$
Hence, the correct answer is option: 'A'.