# Very basic pre-calc

1. Aug 28, 2004

### 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]

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

Last edited: Aug 28, 2004
2. Aug 28, 2004

### Gokul43201

Staff Emeritus
Last edited: Aug 28, 2004
3. Aug 28, 2004

### andrea1

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

4. Aug 28, 2004

### Gokul43201

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

5. Aug 28, 2004

### Math Is Hard

Staff Emeritus
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.

6. Aug 28, 2004

### HallsofIvy

Staff Emeritus
[-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 [tex]-\sqrt{5}<= x<= -\sqrt{2}$$.