Which of the following is equal to 2^12-2^6/2^6-2^3?
A.2^6+2^3
B.2^6-2^3
C.2^9
D.2^3
E.2
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Exponents
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zagcollins
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mbaapplicant2008
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cramya
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I think this problem has been solved in the forum.
2^12 - 2 ^ 6 = (2^6+2^3) (2^6-2^3) [
a ^ 2 - b ^ 2 = (a+b) (a-b)]
2^6-2^3 cancels out in the NUMERATOR AND DENOMINATOR leaving
2^6+2^3 as the answer
Hope this helps!
2^12 - 2 ^ 6 = (2^6+2^3) (2^6-2^3) [
a ^ 2 - b ^ 2 = (a+b) (a-b)]
2^6-2^3 cancels out in the NUMERATOR AND DENOMINATOR leaving
2^6+2^3 as the answer
Hope this helps!
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amitabhprasad
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I think you guys are trying to multiple exponents with same base. While exponents are added/subtracted with same base not multipled
(2^6 ) (2^2) is not the same as 2^12divs wrote::!: ...still a beginner.... But can someone tell me why it cant be solved this way ?!
2^6 ( 2^2 -1 ) / 2^3 ( 2^2 -1 )
= 2^6 / 2^3
= 2^3 :!:
Remember that when you multiply integers with exponents , the exponents add together , they do NOT multiply themselves
Therefore
(2^6)(2^2) = 2^8 is not the same as
(2^6)(2^6) = 2^12 Be careful this GMAT Creators know about this easy mistakes
But again !! u never know the trap ! or the mistake we make 
