Solve for x\in\mathbb{R}
x^{\frac {1}{10}}
+ x^{\frac {1}{15}}
+ x^{\frac {1}{30}} = 84
if x=4^{30}
then x^{1/10}+x^{1/15}+x^{1/30}=4^3+4^2+4=84
then x=4 is a solution
if x<4^{30}
the function will be less than 84
because x^{1/10}<(4^{30})^{1/10}, x^{1/15}<(4^{30})^{1/15}, x^{1/30}<(4^{30})^{1/30}
same can be said if x>4^{30}
thus the only solution is x=4^{30}
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