11. But its projection onto the " x "-axis is the closed interval , which is not an analytic set. 12. Under the operation, dozens of Border Patrol agents stand at close intervals for a two-mile stretch of the river. 13. :: It is fine for positive numbers; for 0 there is a problem if you are using closed intervals . 14. The basic algebraic operations for real interval numbers ( real closed intervals ) can be extended to complex numbers. 15. The "'closure "'of is the smallest closed interval that contains; which is also the set augmented with its finite endpoints. 16. Let and be two functions satisfying the above hypothesis that is continuous on and is integrable on the closed interval . 17. Let be a closed interval of the real line; then a " tagged partition " of is a finite sequence 18. A "'Jordan arc "'in the plane is the image of an injective continuous map of a closed interval into the plane. 19. These are used to delimit a closed-closed interval in mathematics, that is one which includes both the start and end points. 20. About closed intervals ; that exactly how I called them too until talk ) 09 : 52, 14 December 2008 ( UTC)
