Solve Pre-Calc Interval Inequalities | Basic Tutorial

[andrea1]

i just started pre-calc, we were not taught anything and yet given an assignment. i am sure these are very basic and perhaps dumb problems to be stuck on, but i don't get what to do.

"express the interval using inequalities, and give a sketch of the numbers in the interval."

1) [-3,-1]

2) [*rad*5, -*rad*2]

there is more, but if someone can just explain what i do that'd be great!

 

[Gokul43201]

http://www.sosmath.com/algebra/inequalities/ineq02/ineq02.html

http://id.mind.net/~zona/mmts/miscellaneousMath/intervalNotation/intervalNotation.html

No idea what the rads are all about ! Are you talking about square roots, by any chance ?

ie., do you mean \sqrt{2} ?

 

[andrea1]

yes i do, didn't know how to make that

 

[Gokul43201]

yes i do, didn't know how to make that

To see the code used to make that, just click on it.

 

[Math Is Hard]

Did your teacher explain to you what the brackets mean vs. parenthesis, and talk about the difference between open and closed intervals?
Your teacher might be assuming you covered these topics in algebra 2 and this is just review.

 

[HallsofIvy]

[-3, -1] is -3<= x<= -1.

Did your text actually have "*rad*" or did you choose that as a way of writing
\[sqrt{5},-\sqrt{2}]? Well, even if you did, it would make no sense: \sqrt{5} is NOT less than -\sqrt{2}. If the original problem was [-\sqrt{5},-\sqrt{2}] then that is -\sqrt{5}&amp;lt;= x&amp;lt;= -\sqrt{2}.