Rationalize all denominators 1 / ∛(18x^4)

1
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∛(18x^4)

1) I suppose, the denominator is ∛(18*x^4)?

==> ∛(18x^4) = (x)*∛(18x)

2) Multiplying by 12*x² the part inside the cube root, it changes as: (x)*∛{(18x)(12*x² )}

= (x)*)*∛{(216*x^3)} = (x)*(6x) = 6x²

3) So we have to rationalize the denominator with ∛{(12*x²)}

==> 1/*∛{(18*x^4) = ∛(12*x²}/{∛{(18x)(12*x² )} = ∛(12*x²)/6x²