Volume and Surface Area of ​​Cylinder

In geometry, tube or cylinder is built of three-dimensional space formed by two identical parallel circle and a rectangle that surrounds the circle. The cylinder has three sides and two ribs. Both of the circle is called the base and lid, blanket which enveloped the tube is an rectangle.

• The tube consists of the base and curved sides (covers); 
• The top and base are congruent circular;
• Lines EA, EB and EC is the radius of the tube;
• The line AB is the diameter of the tube;
• AG dan BF is the height of the tube.

Area of Blanket

To determine the cylinder blanket by opening the cylinder without the top and base sides. so a rectangle formed.

• Length of rectangle = circumference of the cylinder base (circle)  = 2 πr 
• Width = cylinder height (h)

Then the cylinder area:

= Area of ​​rectangle

= 2πr h

Example :

Radius of cylinder is 20 cm. If height of cylinder 15 cm and π =3,14. What is area of blanket ?

Area = 2πr x h

        = 2 x 3,14 x 20 x 15

        = 6,28 x 20 x 15

        = 125,6 x 15

        = 1.884 cm 2

• Surface area of cylinder

Surface area cylinder is the sum of the cylinder blanket area, which is a rectangular with the upper and bottom side of the cylinder which is a circle.

Area = 2πr(h +r)

            = 2 x 3,14 x 20 (15+20)

         = 6,28 x 20 (35)

         = 125,6 x 35

            = 4.396 cm2

• Volume of cylinder 

Cylinder is a prism whose base is a circle, so to calculate the volume of the cylinder can be used prism volume 

Volume = πr2 h

              = 3,14 x 20 x 20 x 15

              = 6,28 x 20 x 15

              = 1.256 x 15

              = 18.840 cm3

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How to create a blog updates to twitter and facebook

How to create a blog updates to twitter and facebook  is now believed to apply in this blog, and the results are seen always update this blog on Twitter and Facebook. Though I myself do not necessarily make a post once a month. Immediately, I explain how I make our blog look updated every day without making a postingpun. Here are the steps to juggle your blog is always updated look at Twitter and Facebook without making a post:

1.  Go to twitterfeed.com.

On the login page twitterfeed enter your email address and password. If you do not already have  an account twitterfeed, please do the registration by clicking on [Do not have an account yet?].

     After entering the Twitterfeed dashboard, click the [Create New Feed]

On page [Step 1: Name & Add Feed Source URL] we will take blog comments feed. Enter the address of your blog feed comment on the column [Blog URL or RSS Feed URL] and press the [test rss feed]. If it works then there is a notice √ Feed parsed OK. To find out how RSS Feed URL address  use the mouse right-click on the "home" to your blog, then select "View page source" looking for your blog RSS code.  

Then click the [Advanced Settings] to set a feed:

 a. Check for new posts: Every 30 mins.

 b. Post up to: 5.

 c. Post Content Include: description only (recommendation from me, to avoid duplicate titles).

Click continue step 2 :

Then on page [Available Services] is where we can link to the comment feed Twitter and Facebook. So that whenever there are new comments on your blog, it will automatically be distributed to Your  Twitter and Facebook accounts. 

To start linking to your Twitter account and Facebook, please click the link Twitter and Facebook Facebook.Untuk click [Connect with Facebook] and then enter the e-mail address and password of your Facebook. Besides, other than to distribute to your Facebook profile, it can also pass it on to the Facebook Fan Page or Facebook Group. Look at the picture above. After that click All Done Button.

New comments on your blog, it will automatically fill the comment will be shared to Twitter and Facebook by including a short link to the post that has been commented upon it. Now even if you do not do an update a month or a year long in your blog someone commented it is as if your blog looks is always updated. Of course this is very beneficial for those who have a lot of followers and liqueur, because able to attract people to come to your blog.

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How to Make Twitter Account

Twitter was changed to be more dynamic graphics display, and this tutorial is made for those wishing to make a twitter with the latest look in 2012. Prepare an email, For those who do not have email or forgot the email password is recommended to create a new e-mail - See how to create e-mails in gmail. 

Go to twitter.com. The initial view of twitter :

1.  Fill in the registration on the bottom left box, See the first picture.
     - The first column fill in the name (at least 2 words)
     - Fill in the e-mail you used to create a twitter
     - Fill with the password or the password to enter later on to finish creating a twitter 
        account  twitter. and then sign up into Twitter :
2.  Your information will appear, when you are done click create my acount, will open a new 
      page :

3. To have a twitter account you should follow at least 5 people on twitter, on the left page is 

     provided several recommendations, just click the Follow as many as 5 people. After that 

     click next.

4.  Find and follow well known people,  and then click next
5.  From here we skip this step, click "skip this step", the bottom of the box. You can find 
      friend and add character later. 
6.  Go to your e-mail and follow the link to complete registration. 

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Complete tutorial how to create facebook

As we know that now is the use of social networking site Facebook is growing. Its consumer not only adults but children of school age were already familiar with and have a facebook account. This time I will make a simple guide for beginners how to create facebook. In order to make it easier, it is accompanied by a picture tutorials.Before signing up facebook do not forget to set up an email address. Do you already have an e-mail or not? If you do not have e-mail address, create an e-mail first. Please read the previous article how to create e-mail.

The first time we have to do is log onto facebook home page.

Fill in the requested data in the fields such as name, last name, email, password, gender, and date of birth. Once loaded it, then click the sign up button. 

• A form of find friend will appear, select skip this step, and go to profile information. You can perform this step later after the account is created;
• Next step is profile information : fill the form with your high school and college/university (or leave it blank, and fill the information later), and then click save and continue.
• Next step is profile picture. In the profile picture you can upload an image from your computer or with your webcam, and then save and continue. 

• Confirmation message will appear, go to your e-mail to complete the sign-up process.
• Follow the link by clicking and go to your facebook acount.
• Now complete your profil with find friend and edit profile. 

You also can make a fecebook fan page by follow this article : Facebook Fan Page.

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