SOLUTION: 2x^(2/3) - 5x^(1/3) - 12 = 0 solve for x

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Question 348365: 2x^(2/3) - 5x^(1/3) - 12 = 0 solve for x
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Use a substitution, u=x%5E%281%2F3%29, u%5E2=x%5E%282%2F3%29
2u%5E2+-++5u+-+12+=+0
2u%2B3%29%28u-4%29=+0
Two solutions:
2u%2B3=0
2u=-3
u=-3%2F2
x%5E%281%2F3%29=-3%2F2
highlight%28x=-27%2F8%29
.
.
.
u-4=0
u=4
x%5E%281%2F3%29=4
highlight%28x=64%29