# NIELIT 2019 Feb Scientist D - Section D: 15

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The roots of the equation $x^{2/3}+x^{1/3}-2=0$ are :

1. $1, -8$
2. $-1, -2$
3. $\frac{2}{3}, \frac{1}{3}$
4. $-2, -7$

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(A) $1, -8$

$x^{\frac{2}{3}} + x^{\frac{1}{3}} – 2 = 0\\ \> \\ \text{put }x=1 \\ \implies 1 + 1-2 = 0 \\ \> \\ \text{put } x= -8 \\ \implies (-8)^{\frac{2}{3}} + (-8)^{\frac{1}{3}} – 2 = 4-2 -2 = 0$
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