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Maths help

This question really confuses me trying to solve it:

Simplify:

(0.0001/t^8)^-3/4

I never get the answer, which is 100t^6.

Please help, :smartass::frown:
Original post by iPthreefifthteen
This question really confuses me trying to solve it:

Simplify:

(0.0001/t^8)^-3/4

I never get the answer, which is 100t^6.

Please help, :smartass::frown:


The answer is 1000t^6.

Represent 0.0001 as a fraction, then you know that x^(-t) = 1/x^t and then indice laws and so on.
As said above, the answer is actually 1000t^6. Here's a clue for your working:

(0.0001/t^8)^-3/4
= (t^8/0.0001)^3/4
= (10000*t^8)^3/4
... can you do the last 2 steps?
Original post by tomthecool
As said above, the answer is actually 1000t^6. Here's a clue for your working:

(0.0001/t^8)^-3/4
= (t^8/0.0001)^3/4
= (10000*t^8)^3/4
... can you do the last 2 steps?


Thank you, Yes it's clear to me know it must be a typo error on the crappy edexcel book.

I think the last 2 step are:

1.) t^8 * 3/4 = 8/1 * 3/4 = 24/4 = 6 therefore t^6

2.) the same step as above didn't work for me i.e 10000/1 * 3/4 = 7500, but instead I found that if I * the power by ^3 and then square root it twice I get a 1000.

Finally if you times them together you get 1000t^6 , step 2 was a bit unclear for me but I think if I ever come across something similar then I'll just have to stick with that method.
Original post by iPthreefifthteen
Thank you, Yes it's clear to me know it must be a typo error on the crappy edexcel book.

I think the last 2 step are:

1.) t^8 * 3/4 = 8/1 * 3/4 = 24/4 = 6 therefore t^6

2.) the same step as above didn't work for me i.e 10000/1 * 3/4 = 7500, but instead I found that if I * the power by ^3 and then square root it twice I get a 1000.

Finally if you times them together you get 1000t^6 , step 2 was a bit unclear for me but I think if I ever come across something similar then I'll just have to stick with that method.


x4=x.x.x.x x^4 = x.x.x.x

x14=x4 x^{\frac{1}{4}} = \sqrt[4]{x}
A number to the power of 3/4 doesn't mean multiply it by 0.75.
Original post by Clarity Incognito
x4=x.x.x.x x^4 = x.x.x.x

x14=x4 x^{\frac{1}{4}} = \sqrt[4]{x}
A number to the power of 3/4 doesn't mean multiply it by 0.75.


How come it works with t^8, 8/1 * 3/4 = 24/4 = t^6?

That's the only thing that baffles me.
Original post by iPthreefifthteen
How come it works with t^8, 8/1 * 3/4 = 24/4 = t^6?

That's the only thing that baffles me.


t84=t2,(t2)3=t6 \sqrt[4]{t^8} = t^2, (t^2)^3 = t^6 following indice laws. It's just a coincidence.

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