Another Help Implementing Adsense

I am a beginner at all of this an amateur at CSS and HTML. I want to add my adsense into my side bar. The adsense code is:

[please read the forum guidelines for posting code about marking any code in your topic]

<script type="text/javascript"><!--
google_ad_client = "ca-pub-1300426252265454";
/* MotivationStart */
google_ad_slot = "3746833696";
google_ad_width = 160;
google_ad_height = 600;
//-->
</script>
<script type="text/javascript"
src="https://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>

My sidebar code is as follows (copied from wordpress dashboard):

<?php
/**
 * The Sidebar containing the main widget area.
 *
 * @package WordPress
 * @subpackage Twenty_Eleven
 * @since Twenty Eleven 1.0
 */

$options = twentyeleven_get_theme_options();
$current_layout = $options['theme_layout'];

if ( 'content' != $current_layout ) :
?>
		<div id="secondary" class="widget-area" role="complementary">
			<?php if ( ! dynamic_sidebar( 'sidebar-1' ) ) : ?>

				<aside id="archives" class="widget">
					<h3 class="widget-title"><?php _e( 'Archives', 'twentyeleven' ); ?></h3>

<ul>
						<?php wp_get_archives( array( 'type' => 'monthly' ) ); ?>
					</ul>
				</aside>

				<aside id="meta" class="widget">
					<h3 class="widget-title"><?php _e( 'Meta', 'twentyeleven' ); ?></h3>

<ul>
						<?php wp_register(); ?>

<li><?php wp_loginout(); ?></li>
						<?php wp_meta(); ?>
					</ul>
				</aside>

			<?php endif; // end sidebar widget area ?>
		</div><!-- #secondary .widget-area -->
<?php endif; ?>

Can someone tell me where to insert the code or insert it for me so I can copy and paste? Once I see it done I’ll be able to research and learn it more for the future, I just have no idea where to start.