ex.6

https://drive.google.com/file/d/1EXDGprp0ahHGSKyW3xbkGK-77F6_DIIQ/view?usp=sharing

https://www.google.co.th/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0ahUKEwi5gI2a28rYAhUEvI8KHaohDL8QFgguMAE&url=http%3A%2F%2Fwww.scilab.org%2Fcontent%2Fdownload%2F247%2F1702%2Ffile%2Fintroscilab.pdf&usg=AOvVaw2BtP93kQ7kZgEJ_E7PZ-77