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Fractional Indices

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1. Need help on this question please and an explanation
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3. And these questions

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4. You've done the hard work for the first one. So the cube root of 27 is... and squaring that gives ..
5. Just remember: top is the power and bottom is the root
For the first one: cube root of 27 =?
Then all you do is square that answer (BIDMAS)
I think u can do the others now
6. (Original post by SeanFM)
You've done the hard work for the first one. So the cube root of 27 is... and squaring that gives ..
m8
u beat me to it lel
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this was my time to shine
7. When it comes to fractional indices, the bottom number in the fraction is the root. The top number in the fraction is the exponent. (if it's a 3, you cube the result)
8. (Original post by CheeseIsVeg)
m8
u beat me to it lel
Spoiler:
Show
this was my time to shine
You can help it's fine.
9. (Original post by CheeseIsVeg)
Just remember: top is the power and bottom is the root
For the first one: cube root of 27 =?
Then all you do is square that answer (BIDMAS)
I think u can do the others now

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10. yea so remember that you root the number by the number on the bottom of the fraction and use the number on the top of the fraction as a power after

you must root first then use power it's a rule

YOU MUST REMEMBER THAT IF YOU GET A NUMBER BIGGER THAN WHAT YOU STARTED WITH WHEN YOU HAVE A FRACTION POWER SMALLER THAN 1 YOU GOT IT WRONG!!!!!!!!!!
(Original post by z_o_e)
And these questions

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so the bottom one deal with the minus first that just means the 16/81 is flipped

then use what i said above to finish the question
11. Always do it step by step to avoid mistakes
I think you've not cube rooted it properly
cube root 27 =3 3x3 = 9 n'est pas
Just BIDMAS things and do each step seperately
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(Original post by SeanFM)
You can help it's fine.
#rekt
12. (Original post by fartinugget)
yea so remember that you root the number by the number on the bottom of the fraction and use the number on the top of the fraction as a power after

you must root first then use power it's a rule

YOU MUST REMEMBER THAT IF YOU GET A NUMBER BIGGER THAN WHAT YOU STARTED WITH WHEN YOU HAVE A FRACTION POWER SMALLER THAN 1 YOU GOT IT WRONG!!!!!!!!!!

so the bottom one deal with the minus first that just means the 16/81 is flipped

then use what i said above to finish the question

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13. (Original post by SeanFM)
You can help it's fine.

I did this so far!

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14. (Original post by z_o_e)

I did this so far!

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The cube root of 27 is not the same as 3 * root 27 easy mistake to make.

On your calculator, can you see the shape (it's above the button x^(square)), which is a yellow square, then a root, then another square? That's what you need to find the cube root or anything root that isn't 2. So you press shift and the x^n button and type in what you want to find.

(Though I think you are not supposed to use a calculator, otherwise you could find it straight away but it is useful to check)

15. http://www.thestudentroom.co.uk/atta...0&d=1466345653
^^ wasn't that the original question?

http://www.thestudentroom.co.uk/atta...6&d=1466346204
you didn't flip it

16/18 to the power of -3/4 = 18/16 to the power of 3/4
16. (Original post by fartinugget)
http://www.thestudentroom.co.uk/atta...0&d=1466345653
^^ wasn't that the original question?

http://www.thestudentroom.co.uk/atta...6&d=1466346204
you didn't flip it

16/18 to the power of -3/4 = 18/16 to the power of 3/4
Ohhhhhh so I flip it?

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17. (Original post by z_o_e)
I did this so far!

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http://www.thestudentroom.co.uk/atta...0&d=1466346345
^^ that's bidmas remember powers come before multiplying so your calculator has squared the root of 27 which is 27 and 27x3 is 81
18. (Original post by fartinugget)
http://www.thestudentroom.co.uk/atta...0&d=1466346345
^^ that's bidmas remember powers come before multiplying so your calculator has squared the root of 27 which is 27 and 27x3 is 81
Is this better?

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19. (Original post by z_o_e)
Is this better?

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make sure the root sign covers the whole fraction not just the 81 on the top

(Original post by z_o_e)
Ohhhhhh so I flip it?Posted from TSR Mobile
correct
20. (Original post by fartinugget)
make sure the root sign covers the whole fraction not just the 81 on the top

correct
Yayoo thank you so much

Can you introduce me to locais as that's coming up in tomorrow's end of yr exam.

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