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Exponent Question

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Source: — Problem Solving |

Re: Exponent Question

by logitech » Thu Nov 13, 2008 10:02 am
ablackmon wrote:I cant seem to figure this out:

2^(4-1)^2 / 2^(3-2)....

The test I took said the answer was 2^8 but should it be 2^5?
2^(3)^2/2^1

and here is the TRAP:

You multiplied 3x2 = 6 NO

it is 3^2 so, 3x3=9

This is why the answer is 2^(9-1) not 2^(6-1)

Hope it is clear now. It seems a like little problem but It can turn into a nightmare.
LGTCH
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Re: Exponent Question

by iamcste » Thu Nov 13, 2008 2:07 pm
ablackmon wrote:I cant seem to figure this out:

2^(4-1)^2 / 2^(3-2)....

The test I took said the answer was 2^8 but should it be 2^5?
Tip is simplify expression first to form a ^ m ( since we know that all formulae are around this format)we often looking at such expressions, start looking out for rule and mess up

In this case ,

a. Numerator can be simplified 4-1=3
b. 3^2=9 and not 3*2=6
c. so,numerator 2^9 ( format a ^m)
d. Lets simpliy denominato

3-2=1 hence 2^1

e. (2^9 )/(2^1)

=(a^m)/(a^n)

=a^(m-n)

f. Ans=2 ^(9-1)

Ans 2^8

Note : with ample practice, you can solve such questions in mind and in few sec...

I hope my 2 cents can help
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by cramya » Thu Nov 13, 2008 10:23 pm
1) If its just a^b^c with no parantheses

Do b^c first then a ^ (b^c)



2) If its (a^b)^c then this is equal to a ^ (b*c)


Hope this also helps!
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