1. True

2. False

3. True

4. C

5. D

6. B

7. D

8. A

9. C

10. ???

Results 1 to 8 of 8

- May 7th 2007, 12:02 PM #1

- May 7th 2007, 12:24 PM #2

- May 7th 2007, 12:59 PM #3

- May 7th 2007, 01:00 PM #4

- May 7th 2007, 01:10 PM #5

- May 7th 2007, 02:56 PM #6

- Joined
- May 2007
- Posts
- 60

jan... you got them wrong for him

Well, I guess it's better to explain:

so rational and irrational numbers.

A rational number is one that can be expressed as:

m/n (where m and n are INTEGERS (whole numbers)

1. 1/3 is NOT irrational, why?

because....

1/3 = 0.33 (recurring)

let 0.33 (recurring) = x

10x = 3.33 (recurring)

10x - x = 3

9x = 3

x = 3/9 (3 and 9 are whole numbers!)

therefore the answer is FALSE

2. Already as I have said (m/n for rational numbers)

4/7 are both integers which means that it is RATIONAL

answer: TRUE

3. yup sq. root 2 is IRRATIONAL (you can't express it in m/n)

I think there's another way to prove it too btw but I don't remember it

answer: TRUE

4. sq. root 128 (what's the sq. root sign on the keyboard btw? :S)

sq. root 128 = sq. root 64 x (times) sq. root 2

as we know root 64 = 8

answer = 8 x sq. root 2 = C

5. this is the same as:

- (sq. root 18) x (sq. root 245) you should be able to work this out for yourself

= - sq. root 4410

which is:

- sq. root (441 x 10)

which is the same as:

-21 x sq. root 10 (-21 is sq. root of 441)

answer is D

I'll do the rest later, tired now, hope you understand

zzzzzzzzzzzzzzzzzzzzzzzzzz

- May 7th 2007, 07:56 PM #7

- May 8th 2007, 05:23 AM #8