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If \(1-i\), is a root of the equation \({x^2} + ax + b = 0\), where \(a,b \in R\), then the values of \(a\) and \(b\) are,

Practice this Quadratic Equation question from Engineering Entrance Exam.

Question Details

Easy
Mathematics Quadratic Equation Engineering Entrance Exam
Question

If \(1-i\), is a root of the equation \({x^2} + ax + b = 0\), where \(a,b \in R\), then the values of \(a\) and \(b\) are,

Options
A

2, 2

B

–2, 2

Correct
C

–2, –2

D

1, 2

Solution

Since complex roots always occur in conjugate pair.

\(\therefore \) Other conjugate root is \(1+i\).

Sum of roots \( = \frac{{ - a}}{1} = (1 - i) + (1 + i)\)

\( \Rightarrow a =  - 2\)

Product of roots \( = \frac{{ b}}{1} = (1 - i)(1 + i)\)

\( \Rightarrow b =   2\)

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