Question

What is the inverse of f(x)=5x3 ?


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f−1(x) = 3sqrt25x/5

Answer 1

x = 5y^3
x/5 = y^3
y = (x/5)^(1/3)

Or, if you insist on rational denominators,

y = (25x)^(1/3)/5

your notation would seem to indicate

3√(25x)/5 rather than
cubrt(25x)/5 = ∛(25x)/5