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Destinyyyy
 one year ago
Whats the trick for knowing which ( ) or [ ] go where in interval notation?
Destinyyyy
 one year ago
Whats the trick for knowing which ( ) or [ ] go where in interval notation?

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Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Like... ( infinity sign, infinity sign) ( infinity sign, 1] (3,0] [1,8)

BishopPatton
 one year ago
Best ResponseYou've already chosen the best response.0Let's draw a number line with these four special numbers marked: x <oooo0oooo> +x 3 1 1 3 The trick is to look at the sign (+ or ) of your expression in each one of the intervals where nothing changes sign from + to  or back. These intervals are "up to but not including 3", "strictly between 3 and 1", etc. There are 5 of them. As an example, let's see what happens between 1 and +1. The numerator has one positive factor and one negative factor. The same is true for the denominator. So both numerator and denominator are negative, making the fraction > 0. Now we know that it is >= 0 in the interval (1,+1). Remember the fraction is 0 for x=1 and undefined for +1, so we write [1,+1); the square cornered bracket on the left shows 1 IS IN the interval we are talking about where the fraction is >= zero. With me so far? Now do this kind of analysis about the 4 other subintervals to see what happens. As for the graph for such a problem, just draw on the number line to show what x values are included. There are two ways to show that an end point is or isn't included in the graph. Some books use "[" and "(" for this and some use a filleddot and hollowdot for it. Look in your book. I hope this helps.

BishopPatton
 one year ago
Best ResponseYou've already chosen the best response.0i am tired as heck after having to type that lol

BishopPatton
 one year ago
Best ResponseYou've already chosen the best response.0Please medal and fan if this helps you

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1note when one of the numbers infinity or  infinity it's always a '(' or ')'

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0I have no clue what dot things your talking about. I dont have a book to look at

BishopPatton
 one year ago
Best ResponseYou've already chosen the best response.0if you read everything outloud to yourself it will make sense

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0My examples show ( ) and [ ]

BishopPatton
 one year ago
Best ResponseYou've already chosen the best response.0That is all i can do to help. i hope you understand

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0I rather no draw a number line for every problem I do.. Is there a easier way

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0It doesnt matter if I read it allowed or not I dont understand anything you said.

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1one of your examples is (3,0] that means 'greater than 3 and less than and including 0'.

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Okay I get that.. And my examples were just to show someone what Im talking about

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1so are you happy with the answers given?

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Um not really.. Im still where I was before.. Can you maybe give me an example to solve or something? Im working with domain and range right now

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1ok so what does [ , INf sign) mean

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0? Like [1, infinity sign) ??

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Okay.. [ means less than and including 1.. ) means greater than infinity

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1No It means greater than and including 1 and up to infinity

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1 in other words all numbers from and including 1 and going on infinaiely

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1well try an easy one {3 , 6) this is all numbers greater than and including 3 and less than 6 the [ means that 3 is included and the ) at the end means 6 is NOT included

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1that the square bracket [

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1also its important to remember that its a continuum of numbers between these to values not just 4 and 5 its 3.9011, 5.5 , 5.9999 and whatever

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0This is what im working on. I really understand what you just said. Im trying to but its not making any sense to me

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0I dont care about that. I just want to know how to know where to put () and []

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0I assumed there was some trick people knew that helped them figure it out quick.

triciaal
 one year ago
Best ResponseYou've already chosen the best response.0when you have square it includes the end values

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1the domain is all the values of x that the function can take the empty circle means that that values of x is not included and the filled means that values of x is included.

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1yes the domain for that function is (3,0]

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1the x 3 has the emplty circle but x = 0 has filled one

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Yeah.. But how do you know where to put the 9 and ] at??

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1well ( when the number is not included  so it comes before the 3

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1dw:1441818059986:dw

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Um okay I think I understand that..

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0So the range would be (5,4] ??

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1the lowest value of y comes first in the range this is 5 and the highest is 5

welshfella
 one year ago
Best ResponseYou've already chosen the best response.14 is included but 5 is not

Destinyyyy
 one year ago
Best ResponseYou've already chosen the best response.0Okay I think I understand
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