SOLUTION: (x + 2)^2/3 + 3(x + 2)^1/3 - 10 = 0

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Question 314670: (x + 2)^2/3 + 3(x + 2)^1/3 - 10 = 0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Substitute first.
Let u=%28x%2B2%29%5E%281%2F3%29, then
u%5E2=%28x%2B2%29%5E%282%2F3%29
%28x%2B2%29%5E%282%2F3%29%2B3%28x%2B2%29%5E%281%2F3%29-10=0
u%5E2%2B3u-10=0
%28u%2B5%29%28u-2%29=0
Two "u" solutions:
u%2B5=0
u=-5
%28x%2B2%29%5E%281%2F3%29=-5
x%2B2=-125
x=-127
Not a valid solution since (-127)^(2/3) is undefined.
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.
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u-2=0
u=2
%28x%2B2%29%5E%281%2F3%29=2
x%2B2=8
x=6