JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://knockoutjs.com/downloads/knockout-2.2.0.js"></script>
<div data-bind="foreach: items">
    <input type="text" data-bind="value: $data.v"/>
</div>
<input type="text" data-bind="value: Task1"/>

JavaScript

var ViewModel = function() {
  this.items = ko.observableArray([
    { v:ko.observable("Task One") },
    { v:ko.observable("Task Two") },
    { v:ko.observable("Task Three") }
  ]);
  this.Task1 = ko.computed(function() {
    return this.items()[0].v();
  }, this);
  
  this.items()[0].v('Что-то другое');
  

};
                                         
ko.applyBindings(new ViewModel());