Help! I can't figure out how express a domain in interval notation. - Page 1

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[ARCHIVED THREAD] - Help! I can't figure out how express a domain in interval notation.

Posted: 8/29/2017 8:16:27 PM EDT

I need to express the domain of 1/x-4 in interval notation. Now the domain should be all real numbers except for 4, because if you plug 4 in you'll have 0 on the bottom which don't work. I'm completely lost how to write this. Any help is appreciated because this homework is due in 12 hours and 45 minutes.

Posted: 8/29/2017 8:20:33 PM EDT

[#1]

Actually I figured it out. (-infinity, 4) U (4, infinity).

Posted: 9/1/2017 2:54:26 PM EDT

[#2]

Quoted:
Actually I figured it out. (-infinity, 4) U (4, infinity).

View Quote

(-inf, <4)U(>4,+inf)

But it has been a long time.

Posted: 10/6/2017 6:25:14 AM EDT

[#3]

I think OP is right. If I remember correctly, the parenthesis means not including while a bracket would mean including. so (- infinity, 4]U[4, infinity) would mean all real numbers really.

Posted: 10/6/2017 1:03:05 PM EDT

[#4]

Quote History

Quoted:
I think OP is right. If I remember correctly, the parenthesis means not including while a bracket would mean including. so (- infinity, 4]U[4, infinity) would mean all real numbers really.

View Quote

If you put 4 inside the brackets with no other notation it is included.
(- infinity, <4]U[>4, infinity)

You would have made 4 included and NOTHING outside.

Posted: 10/6/2017 1:39:07 PM EDT

[#5]

(- infinity,<4)U(>4,infinity)

Why not this one?

Posted: 10/6/2017 2:46:37 PM EDT

[#6]

Quote History

Quoted:
(- infinity,<4)U(>4,infinity)

Why not this one?

View Quote

In the domain notation, you don't list symbols, such as < and >. The notation only includes the endpoints of the domain, and the use of parentheses, (, ), or brackets, [, ], indicate whether the endpoint is part of the domain or not.

Mike

Posted: 2/20/2018 2:34:03 AM EDT

[#7]

Quote History

Quoted:

In the domain notation, you don't list symbols, such as . The notation only includes the endpoints of the domain, and the use of parentheses, (, ), or brackets, [, ], indicate whether the endpoint is part of the domain or not.

Mike

View Quote

Spot on Mike.

[ARCHIVED THREAD] - Help! I can't figure out how express a domain in interval notation.

General » Math And Science

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