Set C consists of all of the positive integer multiples of 5 that are less than 20. Set D consists of all of the factors of 20. Which of the following is C |_| D?

(Where that |_| is like a wide lower case "u," a symbol I've never encountered before).

{1,2,4,5,10,15,20}
{2,4,5,10,15}
{5,10}
{5,10,15,20}
{2,4,5,10}

The U means union, so it's the all of the numbers from C combined with all of the numbers in D.

So the answer is {1,2,4,5,10,15,20}

Thanks. I'll probably have more in a little bit.

http://en.wikipedia.org/wiki/Union_(set_theory)

Ok maybe I'm not understanding something here and this is really obvious, but

If 299 is divisible by 2B, and B represents a positive digit, what is the value of B?

2
3
4
6
9

I really hope it's that I haven't finished this coffee that's making that confusing to me.

Assuming 2B means twenty-B and not 2xB, it has to be 3 or 9 because an odd number can't have an even factor. 299/23 is 13, so B is 3.

oohh bad notation ftw

I'm with you except since when does 2B mean twenty-B

aha, i was pretty confused by that problem before as well. good thinking, andyslash

I'm with you except since when does 2B mean twenty-B

when the question writer sucks

I'm with you except since when does 2B mean twenty-B

in a sane world, never

Oh ok. I don't feel so bad now.

sue them!

2B for god's sake jesus fucking christ how on earth could that mean twenty-something?!? REVOLUTION!!!

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.

sue them!

2B for god's sake jesus fucking christ how on earth could that mean twenty-something?!? REVOLUTION!!!

its a dumb and awkward way of asking a dumb question. why couldnt the options have been
23
24
26
29

If the domain of f is given by x={9,0,-9}, what is the range of the function f(x)=x^2+9x

This is probably pretty easy but I don't really remember the gist of the domain/function thing.

Oh wait does it just mean I should plug in 9,0,-9 into the function, hence {0,162} ?

i feel like this knowledge was rolling around in my brain at some point.

:think:

Oh wait does it just mean I should plug in 9,0,-9 into the function, hence {0,162} ?

Yeah, the range would be all possible f(x) values

if 2(the cube root of x) = 3

then x =

why is this not completely obvious

it sounds like you're trying to do the problems without having seen the theory...
or is this unrelated to a math class?

I've seen the theory, it was just 8 years ago.

And yeah, I'm not taking a class.

if 2(the cube root of x) = 3

then x =

why is this not completely obvious

divide both sides by 2, then cube both sides
x=27/8

Durr. Thanks. Over thinking there a bit. 6th grade ravenguy would pwn 25 year old ravenguy.

ravenguy i think my favorite moment of 3rd rock from the sun occurs at 3:55-4:10 of this video YouTube - 3rd RFTS S01 E04- Dick is From Mars, Sally is From Venus (1/3) (http://www.youtube.com/watch?v=avAxpXNi9b0)