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# squareRoot()

Returns the square root of the value, rounded to a representable value.

```
func squareRoot() -> Self
```

## Return Value

The square root of the value.

## Discussion

The following example declares a function that calculates the length of
the hypotenuse of a right triangle given its two perpendicular sides.

```
func hypotenuse(_ a: Double, _ b: Double) -> Double {
    return (a * a + b * b).squareRoot()
}

let (dx, dy) = (3.0, 4.0)
let distance = hypotenuse(dx, dy)
// distance == 5.0
```

---

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