You can put this solution on YOUR website! The way you're writing your question has several meanings. I'm taking it that you're refering to it as:
(x^(1/3))- 2/5 = 0
x^(1/3) = 2/5
(1/3)(lg x) = lg (2/5)
lg x = [lg(2/5)] / (1/3)
Hence,
x = 10^{[lg(2/5)]/(1/3)}
x = 0.064
Kindly use brackets to make the question you are posing clearer. thanks
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