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Maths help please :D

I want to know how to work this out fellow mathematicians! Please help and give me the working out method as well please (i have the answer, but i want to know how to get to that answer). Thanks!

The question is: write a as a^n and state the value of n:

√a^8/3

Thanks again!!!!
Reply 1
Avatar for Notnek
Notnek
21
Original post by theJdog
I want to know how to work this out fellow mathematicians! Please help and give me the working out method as well please (i have the answer, but i want to know how to get to that answer). Thanks!

The question is: write a as a^n and state the value of n:

√a^8/3

Thanks again!!!!

Is that a83\displaystyle \sqrt{\frac{a^8}{3}}, a83\displaystyle \frac{\sqrt{a^8}}{3} or something else?

Also, your question doesn't make complete sense. Can you check that you posted it correctly?
(edited 10 years ago)
Reply 2
Avatar for theJdog
theJdog
OP
14
Original post by notnek
Is that a83\displaystyle \sqrt{\frac{a^8}{3}}, a83\displaystyle \frac{\sqrt{a^8}}{3} or something else?

Also, your question doesn't make complete sense. Can you check that you posted it correctly?

No, it is a fractional indices (so 8/3 is a fractional indices).
Original post by notnek
Is that a83\displaystyle \sqrt{\frac{a^8}{3}}, a83\displaystyle \frac{\sqrt{a^8}}{3} or something else?

Also, your question doesn't make complete sense. Can you check that you posted it correctly?


I think it's supposed to be (a)83(\sqrt a)^{\frac{8}{3}}

OP-try rewriting a=a12\sqrt a=a^{\frac{1}{2}}, then you might see it.
Reply 4
Avatar for Notnek
Notnek
21
Original post by theJdog
No, it is a fractional indices (so 8/3 is a fractional indices).

OK - please use brackets in future.

a83=(a83)12\displaystyle \sqrt{a^{\frac{8}{3}}} = \left(a^\frac{8}{3}\right)^\frac{1}{2}

Now use the index law (ab)c=ab×c\displaystyle \left(a^b\right)^c = a^{b \times c}

EDIT: The poster above has given a similar method if the question isn't as I have assumed.
(edited 10 years ago)
Original post by theJdog
No, it is a fractional indices (so 8/3 is a fractional indices).

a83\displaystyle \sqrt{a^\frac{8}{3}}?
Edit: already beaten
Reply 6
Avatar for theJdog
theJdog
OP
14
Original post by notnek
Is that a83\displaystyle \sqrt{\frac{a^8}{3}}, a83\displaystyle \frac{\sqrt{a^8}}{3} or something else?

Also, your question doesn't make complete sense. Can you check that you posted it correctly?

And the question is: express the following in the form a^n, stating the value of n.
Reply 7
Avatar for lubus
lubus
12
Original post by theJdog
No, it is a fractional indices (so 8/3 is a fractional indices).


to avoid ambiguity, write it as (a^(8/2))^(1/2)

Anyway, used the indice rules and you should get it should be straighforward. Remember that square root is also ^(1/2)
Reply 8
Avatar for cimuuGuitar
cimuuGuitar
√a^8/3
= a^8/3-2
= a^2 2/3-2
= a^2/3

i dont know its true or false:biggrin:
Reply 9
Avatar for theJdog
theJdog
OP
14
Original post by notnek
OK - please use brackets in future.

a83=(a83)12\displaystyle \sqrt{a^{\frac{8}{3}}} = \left(a^\frac{8}{3}\right)^\frac{1}{2}

Now use the index law (ab)c=ab×c\displaystyle \left(a^b\right)^c = a^{b \times c}

EDIT: The poster above has given a similar method if the question isn't as I have assumed.

I did that and i got a^2/3, but apparently that's wrong and it should be 1/3 instead :confused:
Reply 10
Avatar for theJdog
theJdog
OP
14
Original post by cimuuGuitar
√a^8/3
= a^8/3-2
= a^2 2/3-2
= a^2/3

i dont know its true or false:biggrin:

It's apparently false.
Reply 11
Avatar for Notnek
Notnek
21
Original post by theJdog
I did that and i got a^2/3, but apparently that's wrong and it should be 1/3 instead :confused:

It's not 2/3 or 1/3:

83×12=86=43\displaystyle \frac{8}{3}\times \frac{1}{2} = \frac{8}{6}=\frac{4}{3}
Reply 12
Avatar for theJdog
theJdog
OP
14
Original post by notnek
It's not 2/3 or 1/3:

83×12=86=43\displaystyle \frac{8}{3}\times \frac{1}{2} = \frac{8}{6}=\frac{4}{3}

Sorry i meant that :colondollar: do you think that the answer is a typo?????
Reply 13
Avatar for Notnek
Notnek
21
Original post by theJdog
Sorry i meant that :colondollar: do you think that the answer is a typo?????

If the question I posted is exactly the same as the one you see in your book then there is a typo in the answer.
Reply 14
Avatar for theJdog
theJdog
OP
14
Original post by notnek
If the question I posted is exactly the same as the one you see in your book then there is a typo in the answer.

Ok thanks! And yeah i typed it word for word.

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