MGMAT CAT - Exponents

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MGMAT CAT - Exponents

by okigbo » Sat Feb 27, 2010 2:10 am
If n is a non-negative integer such that 12^n is a divisor of 3,176,793, what is the value of n^12 - 12^n ?

a. -11
b. -1
c. 0
d. 1
e. 11

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by sanju09 » Sat Feb 27, 2010 4:56 am
okigbo wrote:If n is a non-negative integer such that 12^n is a divisor of 3,176,793, what is the value of n^12 - 12^n ?

a. -11
b. -1
c. 0
d. 1
e. 11
No positive integer n can make 12^n a divisor of 3,176,793 simply because no EVEN can be a divisor of an ODD. Hence n is none other than 0.

Now, n^12 - 12^n = 0^12 - 12^0 = 0 - 1 = [spoiler]-1[/spoiler].

[spoiler]B[/spoiler]
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by harshavardhanc » Sat Feb 27, 2010 6:18 am
okigbo wrote:If n is a non-negative integer such that 12^n is a divisor of 3,176,793, what is the value of n^12 - 12^n ?

a. -11
b. -1
c. 0
d. 1
e. 11
no power of an even number is odd unless until it is the zeroeth power, which is 1.

hence, n MUST be 0, giving us the value as 0^12 - 12^0 = -1.
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Harsha