# AS questions - i'm stuck plz help!!!!!Watch

This discussion is closed.
#1
Please could you tell me how I would simplify this:

sr=square root

sr3 (3 sr3 - sr 12)

thanks, that's the first question but there's a lot and i know we did it for gcse but i really forget, so if you could give me some help on that and explain how to do it so I can understand the rest and be alright with it in class, it'd be a great help!

thanks everyone
0
14 years ago
#2
rt(12) = rt(4*3) = 2rt(3)

3rt(3) - 2rt(3) = rt(3)

You should know that square root of a = a^1/2, the cubic root of a = a^1/3, the fourth root of a = a^1/3, etc.

So, the 3rd root of [rt(3)] = (3^1/2)^1/3

Using the rules of indices:
(a^b)^c = a^(b*c)

So: (3^1/2)^1/3 = 3^(1/2*1/3) = 3^(1/6), or the sixth root of 3.

Hope that helps, and I hope I understood your question correctly.
0
14 years ago
#3
Wow. Your GCSE results are almost identical to mine. And I come from the hole they call Wirral too. Hehe.
0
14 years ago
#4
(Original post by SsEe)
Wow. Your GCSE results are almost identical to mine. And I come from the hole they call Wirral too. Hehe.
How do u know this????
0
14 years ago
#5
Isn't the question √3(3√3 - √12) ?

In which case the solution is:

= √3(3√3 - √12)
= √3(3√3 - 2√3) <======== (as √12 = √(4 x 3) = √4√3 = 2√3)
= 3√3√3 - 2√3√3
= 3(√3)Â˛ - 2(√3)Â˛
= 9 - 6
= 3
0
14 years ago
#6
(Original post by clairezay)
Please could you tell me how I would simplify this:

sr=square root

sr3 (3 sr3 - sr 12)

thanks, that's the first question but there's a lot and i know we did it for gcse but i really forget, so if you could give me some help on that and explain how to do it so I can understand the rest and be alright with it in class, it'd be a great help!

thanks everyone
I think that the previous poster or I have become confused. I go the answer 3, as follows:
sr3*sr3=3, for obvious reasons. sr(12)=sr(4*3)=2sr3
so you then have :
sr3(3sr3-2sr3), which simplifies to sr3(sr3) which as previously mentioned is just 3.
hope this clarifies it for you.
Dan
0
14 years ago
#7
lol i must have posted right after you! sorry. so at least the answer 3 is confirmed
0
14 years ago
#8
(Original post by dan2004)
lol i must have posted right after you! sorry. so at least the answer 3 is confirmed
lol no problem, 2 heads are better than 1...
0
X
new posts
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

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

### University open days

• University of East Anglia
Fri, 4 Jan '19
• University of Lincoln
Mini Open Day at the Brayford Campus Undergraduate
Mon, 7 Jan '19
• Bournemouth University
Wed, 9 Jan '19

### Poll

Join the discussion

#### Did you get less than your required grades and still get into university?

Yes (48)
29.63%
No - I got the required grades (94)
58.02%
No - I missed the required grades and didn't get in (20)
12.35%