Math Functions in Swift

not in the language itself. There are trigonometric functions in the CoreGraphics framework.

This works directly in SwiftUI or playground or UIKit app as well:

let x = sin(.pi / 6)

Yes.

Just create a new project in SwiftUI:

import SwiftUI

struct ContentView: View {
    var body: some View {
        VStack {
            Image(systemName: "globe")
                .imageScale(.large)
                .foregroundColor(.accentColor)
            Text("Hello, world! \(sin(Float.pi/3))")
        }
        .padding()
    }
}

And get this:

Thanks allot