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?
Exponent Question
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- logitech
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2^(3)^2/2^1ablackmon 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?
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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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 upablackmon 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?
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