Question

The solution of the equation $x^{\frac{2}{3}}+x^{\frac{1}{3}}=2$ is

• A. -8,1
• B. 8,1
• C. 1,-1
• D. 2,-2

Answer 1

The correct option is A -8,1

Let $x^{\frac{1}{3}}=y$
Then $y^2+y-2=0$
or (y+2)(y-1)=0
or y=-2, 1
When y=$-2$

$x^{\frac{1}{3}}$ =-2
or x = -8
When y=$1$

$x^{\frac{1}{3}}$=1
or x=1