NPM

If external library like jQuery is installed using NPM

npm install --save jquery

Add script path into your angular-cli.json

"scripts": [
    "../node_modules/jquery/dist/jquery.js"
]

Assets Folder

You can also save the library file in your assets/js directory and include the same in angular-cli.json

"scripts": [
    "assets/js/jquery.js"
]

Note

Save your main library jquery and their dependencies like jquery-cycle-plugin into the assets directory and add both of them into angular-cli.json, make sure the order is maintained for the dependencies.

To use jquery in your Angular 2.x components, declare a global variable on the top

If using $ for jQuery

declare var $: any;

If using jQuery for jQuery

declare var jQuery: any

This will allow using $ or jQuery into your Angular 2.x component.