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# Indices watch

1. Could someone please explain this to me?
2. (Original post by razzy02)

Could someone please explain this to me?
What is 81^(1/4), first of all? How can you work out what it is?

Same logic for the 25 term

Then see how to put that knowledge together
3. (Original post by SeanFM)
What is 81^(1/4), first of all? How can you work out what it is?

Same logic for the 25 term

Then see how to put that knowledge together
So 81^(1/4) is 3, and 25 ^ (-1/2) is 50 and then I would multiply them together.
Is this correct?
4. (Original post by razzy02)
So 81^(1/4) is 3, and 25 ^ (-1/2) is 50 and then I would multiply them together.
Is this correct?
Not quite for the part in bold.

If, like you correctly calculated,
Then, first of all what would be?
5. (Original post by KaylaB)
Not quite for the part in bold.

If, like you correctly calculated,
Then, first of all what would be?
It would be 5
6. (Original post by razzy02)
It would be 5
Correct , and what does a negative power mean?
7. (Original post by KaylaB)
Correct , and what does a negative power mean?
You see that's where I begin to struggle with the question! would I have to flip the fraction upside down?
8. (Original post by razzy02)
You see that's where I begin to struggle with the question! would I have to flip the fraction upside down?
Ah I see! For negative indices, it means you do 1 over the x value without the negative sign. It doesn't make much sense when I'm typing it, so I apologise, hopefully this image will show you what I mean

So in the same way as the graphic above. How else can be written?
9. (Original post by KaylaB)
Ah I see! For negative indices, it means you do 1 over the x value without the negative sign. It doesn't make much sense when I'm typing it, so I apologise, hopefully this image will show you what I mean

So in the same way as the graphic above. How else can be written?
Thank you so much!! So it would be 1/25^1/2?
10. (Original post by razzy02)
Thank you so much!! So it would be 1/25^1/2?
No problem

Yes it would be

So, if we already know what is equal to, then what is ?
11. (Original post by KaylaB)
No problem

Yes it would be

So, if we already know what is equal to, then what is ?
1/5!!
12. (Original post by razzy02)
1/5!!
Yes! Well done!

So finally, can you now tell me what is equal to?
13. (Original post by KaylaB)
Yes! Well done!

So finally, can you now tell me what is equal to?
That would be 3 x 1/5 = 0.6 xx
Thank you so much for all your help!!!
14. (Original post by razzy02)
That would be 3 x 1/5 = 0.6 xx
Thank you so much for all your help!!!
That's correct, good job!

Glad that I could be of assistance
15. to work out something to the power of 1/4 you simply find the square root, then find the square root again. eg 81=9=3.

when finding out a negative power you need to make it positive by flipping the fraction so there its 25 to the power of -1/2 changes to just 1/2 meaning square root of 25 which is 5.

Then multiply 3 and 5 to get the final answer.
16. (Original post by keeleighgeorge)
to work out something to the power of 1/4 you simply find the square root, then find the square root again. eg 81=9=3.

when finding out a negative power you need to make it positive by flipping the fraction so there its 25 to the power of -1/2 changes to just 1/2 meaning square root of 25 which is 5.

Then multiply 3 and 5 to get the final answer.
I'm afraid that isn't correct. See above for how to approach this question

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