Merge pull request #52 from cookednoodles/patch-1

Update column1.md

Author: ctritten

src/react/first-side/column1.md

@@ -8,7 +8,7 @@ We call this a “root” DOM node because everything inside it will be managed
 
 ```js
 const element = <h1>Hello, world</h1>
-ReactDOM.render(element, document.getElementById('root'))
+ReactDOM.createRoot(document.getElementById('root'));
 ```
 
 # React Element
@@ -27,7 +27,8 @@ class HelloWorld extends React.Component {
   }
 }
 
-ReactDOM.render(<HelloWorld />, document.getElementById('root'))
+const root = ReactDOM.createRoot(document.getElementById('root'));
+root.render(<HelloWorld />);
 ```
 
 ## A Simple function
@@ -43,5 +44,6 @@ const HelloWorld = () => {
   );
 }
 
-ReactDOM.render(<HelloWorld />, document.getElementById('root'))
+const root = ReactDOM.createRoot(document.getElementById('root'));
+root.render(<HelloWorld />);
 ```