SOLUTION: Solve for x a) x^(2/3) -x^(1/3) - 2 = 0 Can you please help me out? Thanks so much in advance:) Can you also please show me the steps it would help me understand better:)

Algebra ->  Exponents -> SOLUTION: Solve for x a) x^(2/3) -x^(1/3) - 2 = 0 Can you please help me out? Thanks so much in advance:) Can you also please show me the steps it would help me understand better:)      Log On


   

Question 754077: Solve for x
a) x^(2/3) -x^(1/3) - 2 = 0
Can you please help me out? Thanks so much in advance:)
Can you also please show me the steps it would help me understand better:)
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x
a) x%5E%282%2F3%29+-x%5E%281%2F3%29+-+2+=+0
This can be factored just like a normal quadratic equation
%28x%5E%281%2F3%29-2%29%28x%5E%281%2F3%29%2B1%29 = 0; FOIL this & you can prove it to yourself
Two solutions
x%5E%281%2F3%29 = 2
Cube both sides and you have
x = 8
and
x%5E%281%2F3%29 = -1
cube both sides and you have:
x = -1
:
:
Check this, replace x with 8 and -1 in the original problem
Only x = 8 is a valid solution