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Exponents and Fractions

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by tohellandback » Tue Jul 14, 2009 9:31 pm
1/5)^m * (1/4)^18 = 1/2(10)^35

or, 1/5)^m * (1/2)^36 = 1/2*(1/2)^35*(1/5)^35
or, 1/5)^m * (1/2)^36 = (1/2)^36*(1/5)^35
m=35
The powers of two are bloody impolite!!
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by ketkoag » Wed Jul 15, 2009 8:35 am
same approach as above..
35 it is..
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by uw490 » Wed Jul 15, 2009 9:42 am
I'm a little rusty on my rules for exponents...

But, how can you turn (1/4)^18 into (1/2)^36 and how can you turn (10)^35 into (1/2)^35*(1/5)^35???

An explanation of the above would really help me out.

thanks
J
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by mike22629 » Wed Jul 15, 2009 9:58 am
First think of it this way:

What does (1/2)^36 actually equal?

It equals:
(1^36)/(2^36)

Now what does 4^2 = ?
It equals 16 or 2*2*2*2 or 4*4

So.....
2^36 = 4^18
(There are the same number of 2s on both sides of equation, they are just written differently. Remember that 4 = 2*2, so 4 is essentially two 2s.

Just as 4^2 = 2^4

And you do not turn 10^35 into (1/2^35)*(1/5^35)

You turn 1/(10^35) into (1/2^35)*(1/5^35)
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by uw490 » Wed Jul 15, 2009 10:23 am
Got it!

Thanks for the explanation, this clears it up!
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