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/// Options:
// -> call the `cbrt()` function
// -> call the `powf()` function with 1/3
//
/// Example:
fn main() {
let x = 2f64; // or f32
let sqrt = &x.cbrt(); // call sqrt()
let sqrt2 = &x.powf(1/3); // call powf()
}
/// Note:
// The second option can also be applied to other
// roots. For the nth root it is then powf(1/n).
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