dkenrgyfrk
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scientific notation root powers exponents question
scientific notation
I have a problem that displays the 4th root of the square root of 5.2 x 10 to the -9th power
4 -9
sq rt of 5.2 X 10
I hope that shows up right.
| Code: | 4 -9
sq rt of 5.2 X 10
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The answer I get is +- 8.5 x 10 to the negative 3rd power
but the book is giving me an answer of +- 2.7 x 10 to the -2nd power
I get the +- because it's an even root which means an absolute or + or - number can be squared.
I moved the decimal place 3 places to the right so that the power of -12 can be easily divided by the power of 4.
I tried reversing the decimal place as well so that the power is -8.
I am not getting why I am not coming up with the same answer as the book. I really believe the book is in error.
Can anyone verify either of these and please explain what I am doing wrong if I am incorrect?
Thank you so much in advance.
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dkenrgyfrk
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I was afraid of that. The top version of it has the 4-9. It shouldn't look like that. The 4 is before the square root sign and the -9 is suppose to be
the power of the 10 within the square root.
Ugh, I hope that explains it enough.
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Magpie
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I get a 3rd answer (sorry):
5.2 x 10^-9 = 0.52 x 10^-8
(0.52 x 10^-8)^1/2 = 0.7211 x 10^-4
(0.7211)^1/4 = 0.9215
(10^-4)^1/4 = 10^-1
0.9215 x 10^-1 = 9.215 x 10^-2
The single most important condition for a successful synthesis is good mixing - Nicodem
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turd
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The 4th root of something is per definition NOT a square root. Simply say the 4th root. And yes, the 4th root of 5.2E-9 is approximately 0.00849. Scan
your book and post it here.
Edit: this forum has preview and edit functions. You can use them as this self-referential comment demonstrates.
Edit2: The square root of y is usually defined as the positive solution to the equation x^2-y=0. So the solutions to x^2-y=0 are x=+sqrt(y)
and x=-sqrt(y). Same for nth roots (n even). Roots are perfectly defined and you don't have to mess with that +/- thing.
[Edited on 18-1-2012 by turd]
[Edited on 18-1-2012 by turd]
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