JEE MATHEMATICS MCQ: COMPLEX NUMBERS

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Analyzing +4 | -1

a = \cos \left( {\frac{{2\pi }}{7}} \right) + i\sin \left( {\frac{{2\pi }}{7}} \right),\;

then the quadratic equation whose roots are

\mathrm{\alpha } = a + {a^2} + {a^4}\;\mathrm{and}\;\mathrm{\beta } = {a^3} + {a^5} + {a^6}

View answer and explanation

Correct option: D

{x^2} + x + 2 = 0

Option D (

{x^2} + x + 2 = 0

) is correct because calculating the sum and product of the roots α and β leads to this quadratic equation.

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