4^17=2^34;gayu wrote:what is the greatest prime factor of 4^17 - 2^28?
A)2 B)3 C)5 D)7 E)4
therefore; 2^34-2^28;
2^28(2^6-1);
2^28*63;
now 63 is divisible by 7; hence greatest prime factor is 7..!!!!
greatest prime factor
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manpsingh87
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therefore; 2^34-2^28;
2^28(2^6-1);
2^28*63;
now 63 is divisible by 7; hence greatest prime factor is 7..!!!!
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