Let $\alpha$ be a root of the equation 1 + x2 + x4 = 0. Then, the value of $\alpha$1011 + $\alpha$2022 $-$ $\alpha$3033 is equal to :
Solution
<p>Given, $\alpha$ is a root of the equation 1 + x<sup>2</sup> + x<sup>4</sup> = 0</p>
<p>$\therefore$ $\alpha$ will satisfy the equation.</p>
<p>$\therefore$ 1 + $\alpha$<sup>2</sup> + $\alpha$<sup>4</sup> = 0</p>
<p>${\alpha ^2} = {{ - 1 \pm \sqrt {1 - 4} } \over 2}$</p>
<p>$= {{ - 1 \pm \sqrt 3 i} \over 2}$</p>
<p>$\therefore$ ${\alpha ^2} = \omega \,ar\,{\omega ^2}$</p>
<p>Now,</p>
<p>${\alpha ^{1011}} + {\alpha ^{2022}} - {\alpha ^{3033}}$</p>
<p>$$ = \alpha \,.\,{({\alpha ^2})^{505}} + {({\alpha ^2})^{1011}} - \alpha \,.\,{({\alpha ^2})^{1516}}$$</p>
<p>$= \alpha {(\omega )^{505}} + {(\omega )^{1011}} - \alpha \,.\,{(\omega )^{1516}}$</p>
<p>$$ = \alpha \,.\,{({\omega ^3})^{168}}\,.\,\omega + {({\omega ^3})^{337}} - \alpha \,.\,{({\omega ^3})^{505}}\,.\,\omega $$</p>
<p>$= \alpha \,\omega + 1 - \alpha \,\omega$</p>
<p>$= 1$</p>
About this question
Subject: Mathematics · Chapter: Complex Numbers and Quadratic Equations · Topic: Complex Numbers and Argand Plane
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