How to solve the "Undefined variable" error in laravel?

I am using laravel, and I have got an error:

Undefined variable: getFormTest (View: C:\xampp\htdocs\survey\resources\views\tambahformtest.blade.php)

That error references to this view :

<input value="">

I have put $getFormTest in my controller.

public function TambahFormTest()
{
    $ms_id = FormTest::max('ms_id');
    $getFormTest = FormTest::Select('ms_test')->where('ms_id', '=', $ms_id)->get();

    return view('tambahformtest', $getFormTest);
}

via Chebli Mohamed