Solve the equation 3x^2/3 + x^1/3 − 2 = 0

Let u = x^1/3 

The equation can therefore be written as:

3u^2+u-2=0

This can be factorised to:

(3u-2)(u+1)+0 

Therefore: u = 2/3 or u = -1 OR x^1/3 = 2/3 or x^1/3 = -1

So: x = (2/3)^3 or x = (-1)^3 

x = 8/27 or x = -1