You are Here: Home >< A-levels

# Maths Watch

1. What is 51-14 sqrt 2 divided by 3 -2 sqrt 2
2. (Original post by Elisa2000)
What is 51-14 sqrt 2 divided by 3 -2 sqrt 2
It's a secret
Spoiler:
Show
multiply top and bottom by 3+2 sqrt 2
3. (Original post by EricPiphany)
It's a secret
Spoiler:
Show
multiply top and bottom by 3+2 sqrt 2
What did you get overall?
4. (Original post by Elisa2000)
What did you get overall?
I didn't. What did you get?
5. (Original post by EricPiphany)
I didn't. What did you get?
I got 41 -20 sqrt 2
6. (Original post by Elisa2000)
I got 41 -20 sqrt 2
Try again.
7. (Original post by RDKGames)
Try again.
Well, could you show me what the right answer is? Without using a calculator
8. (Original post by Elisa2000)
Well, could you show me what the right answer is? Without using a calculator
Show your working and I'll tell you where you went wrong.
9. (Original post by RDKGames)
Show your working and I'll tell you where you went wrong.
51 - 14 sqrt 2/ 3 -2 sqrt 2 both multiplied by 3+2 sqrt 2. Then I got 153 + 102 sqrt 2 - 42 sqrt 2 - 28 - 2 divided by 9-4-2 which gave me: 123-60 sqrt 2 /3. I divided it by three, which gave me 41 -20 sqrt 20
10. (Original post by Elisa2000)
What is 51-14 sqrt 2 divided by 3 -2 sqrt 2
?
11. (Original post by XOR_)
?
Could you help me with this?
12. (Original post by Elisa2000)
51 - 14 sqrt 2/ 3 -2 sqrt 2 both multiplied by 3+2 sqrt 2. Then I got 153 + 102 sqrt 2 - 42 sqrt 2 - 28 - 2 divided by 9-4-2 which gave me: 123-60 sqrt 2 /3. I divided it by three, which gave me 41 -20 sqrt 20
Well you simply multiplied wrong.

Numerator:

Denominator:

Now simplify and carry on.
13. multiply top and botton by (3 + 2(sqrt2)) to rationalize the denominator

EDIT: left for a few minutes and was answered i cri erry tim
14. (Original post by RDKGames)
Well you simply multiplied wrong.

Numerator:

Denominator:

Now simplify and carry on.
isn't it 3-2sqrt(2)
15. (Original post by XOR_)
isn't it 3-2sqrt(2)
Huh? Where?
16. (Original post by RDKGames)
Huh? Where?
The original questions' denominator.
17. If you want my answer:
Spoiler:
Show
I got 97 - 60√2
18. (Original post by XOR_)
The original questions' denominator.
Yes it is. I'm showing multiplication by the conjugate of it.
19. (Original post by Notch)
Spoiler:
Show
I got 97 - 60√2
Close.
20. (Original post by RDKGames)
Well you simply multiplied wrong.

Numerator:

Denominator:

Now simplify and carry on.
Look, minus sqrt 2 and sqrt 2 when multiplied make minus 2

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: September 18, 2016
Today on TSR

### Degrees to get rich!

... and the ones that won't

### Cambridge interviews pour in...

Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• Poll

## All the essentials

### Student life: what to expect

What it's really like going to uni

### Essay expert

Learn to write like a pro with our ultimate essay guide.

### Create a study plan

Get your head around what you need to do and when with the study planner tool.

### Resources by subject

Everything from mind maps to class notes.

### Study tips from A* students

Students who got top grades in their A-levels share their secrets

## Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.