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mohitsharda
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4^17 = (2^2)^17
=> 2^(2*17) = 2^34
Now, for the question
4^17 - 2^28 = 2^34 - 2^28
=> Take 2 ^28 common out
=> (2^28)*((2^6)-1)
=> (2^28)*(64-1) = (2^28)*63
=> (2^28)*7*(3^2)
So. the greatest prime factor is 7.
=> 2^(2*17) = 2^34
Now, for the question
4^17 - 2^28 = 2^34 - 2^28
=> Take 2 ^28 common out
=> (2^28)*((2^6)-1)
=> (2^28)*(64-1) = (2^28)*63
=> (2^28)*7*(3^2)
So. the greatest prime factor is 7.
MS
