Indices and Surds Hellpppppp!!!!!!! Watch

UnknownDude
Badges: 5
Rep:
?
#1
Report Thread starter 5 years ago
#1
I got this question:

Simply wy

w: \sqrt{6}

y: {3^{-5/2}}

It also says write your answer in surd form.

Please help!!!!
0
reply
TenOfThem
Badges: 16
Rep:
?
#2
Report 5 years ago
#2
(Original post by UnknownDude)
I got this question:

Simply wy

w: √6

y: 3^(-5/2)

It also says write your answer in surd form.

Please help!!!!
\sqrt{ab} = \sqrt{a} \times \sqrt{b}

Split the 6
0
reply
Old_Simon
Badges: 12
Rep:
?
#3
Report 5 years ago
#3
So ! Get started and show us what you did so far.
0
reply
Old_Simon
Badges: 12
Rep:
?
#4
Report 5 years ago
#4
(Original post by arkanm)
Write \sqrt{6} as \sqrt{2\times 3}=\sqrt{2}\times \sqrt{3}=2^{1/2} \times 3^{1/2}. So wy = 2^{1/2} \times 3^{1/2}\times 3^{-5/2}. I think you can finish from here.
The answer is needed in surd form.
0
reply
UnknownDude
Badges: 5
Rep:
?
#5
Report Thread starter 5 years ago
#5
(Original post by arkanm)
Write \sqrt{6} as \sqrt{2\times 3}=\sqrt{2}\times \sqrt{3}=2^{1/2} \times 3^{1/2}. So wy = 2^{1/2} \times 3^{1/2}\times 3^{-5/2}. I think you can finish from here.
(Original post by TenOfThem)
\sqrt{ab} = \sqrt{a} \times \sqrt{b}

Split the 6
(Original post by Old_Simon)
So ! Get started and show us what you did so far.
(Original post by Old_Simon)
The answer is needed in surd form.
Firstly, thanks everyone for the replies. First time on TSR and a good impression !

So what I got so far is \sqrt{2}\times \sqrt{3^{-4}}
0
reply
TenOfThem
Badges: 16
Rep:
?
#6
Report 5 years ago
#6
(Original post by UnknownDude)
Firstly, thanks everyone for the replies. First time on TSR and a good impression !

So what I got so far is \sqrt{2}\times \sqrt{3^{-4}}
so you need to deal with that

\sqrt{3^{-4}}

What does the negative index do

What is the impact of the square root on the power of 4
0
reply
Old_Simon
Badges: 12
Rep:
?
#7
Report 5 years ago
#7
(Original post by UnknownDude)
Firstly, thanks everyone for the replies. First time on TSR and a good impression !

So what I got so far is \sqrt{2}\times \sqrt{3^{-4}}
Nearly spot on.

You need a bracket around root 3.

Then tidy up. Well done !!!

Tenofthem just confusing you.
0
reply
UnknownDude
Badges: 5
Rep:
?
#8
Report Thread starter 5 years ago
#8
(Original post by TenOfThem)
so you need to deal with that

\sqrt{3^{-4}}

What does the negative index do

What is the impact of the square root on the power of 4
Lol, it said leave it in surd form.

(Original post by Old_Simon)
Nearly spot on.

You need a bracket around root 3.

Then tidy up. Well done !!!

Tenofthem just confusing you.
Oh so is that it? Nothing big or special? How would I tidy up?
0
reply
Old_Simon
Badges: 12
Rep:
?
#9
Report 5 years ago
#9
(Original post by arkanm)
So? x^{a/b}=\sqrt[b]{x}^a
Not so anything. It needs to be in surds so it makes sense to work in surds not go to indices then back again. See ? So ?
0
reply
TenOfThem
Badges: 16
Rep:
?
#10
Report 5 years ago
#10
(Original post by UnknownDude)
Lol, it said leave it in surd form.
yes, but you do need to simplify a little
0
reply
Old_Simon
Badges: 12
Rep:
?
#11
Report 5 years ago
#11
(Original post by UnknownDude)
Lol, it said leave it in surd form.



Oh so is that it? Nothing big or special? How would I tidy up?
Well you need to know what root 3 to the power of minus 4 is and what to do with it.
0
reply
cambo211
Badges: 19
Rep:
?
#12
Report 5 years ago
#12
People need to grasp that 'leave it in surd form' doesn't mean 'don't simplify in the slightest'.
0
reply
UnknownDude
Badges: 5
Rep:
?
#13
Report Thread starter 5 years ago
#13
(Original post by Old_Simon)
Well you need to know what root 3 to the power of minus 4 is and what to do with it.
Lol, can you guys just tell me the answer then I work my way to understanding it from there?

Heres the question again:

Simply wy

w:

y:

It also says write your answer in surd form.
And here's my answer:

Is everything correct, fine?
0
reply
cambo211
Badges: 19
Rep:
?
#14
Report 5 years ago
#14
(Original post by UnknownDude)
Lol, can you guys just tell me the answer then I work my way to understanding it from there?

Heres the question again:



And here's my answer:



Is everything correct, fine?
That's correct but \sqrt{2}\times \sqrt{3^{-4}} can be simplified further.
0
reply
Old_Simon
Badges: 12
Rep:
?
#15
Report 5 years ago
#15
(Original post by cambo211)
People need to grasp that 'leave it in surd form' doesn't mean 'don't simplify in the slightest'.
Of course. But why not do any simplifying into surd form not vice versa ?
Although this is a surd question it is the indices bit the OP is struggling with.
0
reply
TenOfThem
Badges: 16
Rep:
?
#16
Report 5 years ago
#16
(Original post by UnknownDude)
Is everything correct, fine?
I already said that you need to tidy up the \sqrt{3^{-4}}

You would not leave a question with \sqrt{16} in it - you would put 4

And you need to think about the negative index and what that means
0
reply
UnknownDude
Badges: 5
Rep:
?
#17
Report Thread starter 5 years ago
#17
(Original post by arkanm)
No, because \sqrt{3^{-4}} can be simplified further. Note that \sqrt{x}=x^{1/2} -- does that help?
(Original post by cambo211)
That's correct but \sqrt{2}\times \sqrt{3^{-4}} can be simplified further.
So the answer would be \sqrt{2}\times {3^{-4/2}}
0
reply
Old_Simon
Badges: 12
Rep:
?
#18
Report 5 years ago
#18
(Original post by arkanm)
No, because \sqrt{3^{-4}} can be simplified further. Note that \sqrt{x}=x^{1/2} -- does that help?
This is just plain out and out wrong. It may be maths but it is not the way to answer this question.
0
reply
UnknownDude
Badges: 5
Rep:
?
#19
Report Thread starter 5 years ago
#19
Oh yeah guys, if your wondering. My answer has to be in surd form.
0
reply
TenOfThem
Badges: 16
Rep:
?
#20
Report 5 years ago
#20
(Original post by UnknownDude)
So the answer would be \sqrt{2}\times {3^{-4/2}}
\dfrac{4}{2} = 2


Again - do you know what the negative index does?
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

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.

Personalise

University open days

  • University of Chester
    Undergraduate Open Day Undergraduate
    Wed, 13 Nov '19
  • Kingston University London
    All faculties involved Undergraduate
    Wed, 13 Nov '19
  • The University of Law
    Solicitor Series: Discover Your Type of Law - LPC and GDL - London Moorgate campus Postgraduate
    Wed, 13 Nov '19

Are you registered to vote?

18-20 years old (yes) (135)
54%
18-20 years old (no) (30)
12%
20-25 years old (yes) (39)
15.6%
20-25 years old (no) (4)
1.6%
25-30 years old (yes) (18)
7.2%
25-30 years old (no) (0)
0%
30-40 years old (yes) (12)
4.8%
30-40 years old (no) (1)
0.4%
40+ years old (yes) (5)
2%
40+ years old (no) (6)
2.4%

Watched Threads

View All
Latest
My Feed