JSFiddle - React, Tailwind, and code Playground
HTML
<div ng-app="myApp">
<div><form name="form1">
<input type="text" ng-model="firstname" required />
</form></div>
<form name="form2">
<button type="submit" ng-disabled="form1.$invalid">Save</button>
</form>
</div>
JavaScript
angular.module('myApp', [])
.controller('dummy', ['$scope', function ($scope) {
}]);