Question

when do we use ( ) when writing Domain or Range of a function? When do we use [ ] ?

Answer 1

( ) = open bracket means Extremes are not included

Answer 2

that indicates not including a point/number, while brackets [] indicate the inclusion of a point/number

Answer 3

how about for intervals?

Answer 4

same thing for intervals. for example the interval for a domain could be [3,8) which would mean including 3, but not including 8

Answer 5

can you please give me an example with a graph or something so that i could understand it better? please!!!

Answer 6

but please help me cause i have a test coming up!

Answer 7

okay sure. is there a specific problem that you need help with? or do you want me to just make something up?

Answer 8

can u make one up?

Answer 9

sure. okay, give me a sec...

Answer 10

ok

Answer 11

how about this problem?

Answer 12

that's the same one i just did :)

Answer 13

hey do u by any chance have alg2/trig?
cause those problems look similar to the ones in my textbook?

Answer 14

I'm actually in calculus, but i have taken algebra 2 and trig

Answer 15

wow ur smart cool!
ok so is that why u put ( ) cause it only approaches the values but will never reach them?!

Answer 16

so then when would we use [ ] ?

Answer 17

Yes you're exactly right! Haha and thank you. But yeah calculus and precalculus are hard... =.=

Answer 18

anyways, [] would be used when it does reach a certain value, like in a piecewise graph

Answer 19

can you also help me with a piecewise?
its cause the teacher doesnt really explain and she goes to fast!

Answer 20

ok

Answer 21

why is precalculus and claculus hard?

Answer 22

wait ur a gurl right?
nice :D

Answer 23

yes i'm a girl :) um i suppose it's just that they introduce alot of new material (very quickly since im in honors) that forces you to think about lots of things at once, because it combines algebra with trigonometry and finding derivitives....and yeah you'll find out later! xD

Answer 24

u dont suppose i know u do i?
cause i think i do.......

Answer 25

really?? That's would be kinda cool/wierd/awkward :D

Answer 26

do u live in a city that starts with an "A"....

Answer 27

nope..... :(

Answer 28

do you go to a school that starts with a "K"?

Answer 29

No, but i know alot of people who go to one that starts with a K and its pretty close.

Answer 30

so u would include [1, 4]?

Answer 31

yes the brackets indicate that you include the x values 1 and 4. if we had (1,4] for example, we would need to put and open circle on the graph at x=1 instead of a filled in circle. the empty circle implies that there is no value at that point, but it approaches that point, while the filled in circle implies that there is a value at that point

Answer 32

wouldnt [5,7] also be it?

Answer 33

so D= [1,4] & [5,7]

Answer 34

yes :)

Answer 35

hey can u help me tomorrow also like at about whenever u have time?
i would appreciate it alot!! ;D
i got to study for other things gotta go thnx for the help ;D

Answer 36

Okay sure! Let's do same time-ish :) talk to you then! Good luck.

Answer 37

thnx ;D
hope u the best also in whtever u going to do ! lol

Answer 38

haha thank you! i'll do my best to pass my next calc quiz! :)

Answer 39

can you read these problems?

Answer 40

oh ok

Answer 41

Anymore questions? :)