JSFiddle - React, Tailwind, and code Playground

HTML

<div ng-app>
    <div ng-controller="CTRL">
        <input type="text" ng-model="val1" />
        <input type="text" ng-model="val2" />
        <input type="text" ng-model="val3" />
        <p>{{'Angular works!'}}</p>
    </div>
</div>

JavaScript

function CTRL ($scope) {
    $scope.val1 = 3;
    $scope.val2 = 4;

    $scope.$watch( 'val1 + val2', function() {
        $scope.val3 = Number($scope.val1) / Number($scope.val2);
    });
}