methode groupe

j c pa ou le problm il m'affiche methode gp doesn't exist

<?php

/*
|--------------------------------------------------------------------------
| Application Routes
|--------------------------------------------------------------------------
|
| Here is where you can register all of the routes for an application.
| It's a breeze. Simply tell Laravel the URIs it should respond to
| and give it the controller to call when that URI is requested.
|
*/
Route::get('salut', function () {
    return 'salut les gens';
});

route::groupe(['prefix' => 'admin'],function(){
    route::get('salut', function(){
        return 'salut les gens';
    });
});

Route::get('/', function () {
    return view('welcome');
});

/*
Route::Controllers([
    'auth'=>'auth\authController',
    'password'=>'auth\passwordController',

]);
*/

merci d'avance