SOLUTION: Please solve. x^(2/3) - x^(1/3) - 12=0

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Question 382810: Please solve.
x^(2/3) - x^(1/3) - 12=0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!

Use a substitution, let u=x%5E%281%2F3%29, then u%5E2=x%5E%282%2F3%29
u%5E2-u-12=0
%28u-4%29%28u%2B3%29=0
Two solutions:
u-4=0
u=4
x%5E%281%2F3%29=4
x=4%5E3
highlight%28x=64%29
.
.
.
u%2B34=0
u=-3
x%5E%281%2F3%29=-3
x=%28-3%29%5E3
highlight%28x=-27%29