What is the great prime factor of 4^17 - 2^28
a. 2
b. 3
c. 5
d. 7
e. 11
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Jameschan168
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Ans should be d = 7Jameschan168 wrote:What is the great prime factor of 4^17 - 2^28
a. 2
b. 3
c. 5
d. 7
e. 11
4^17 = (2^2)^12 =2 ^34
2^34 - 2^28 = 2^28 (2^6 -1) =2 ^28 (63)
Prime factors or 63 = 7 & 3
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Jameschan168
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You got it!
ri2007 wrote:Ans should be d = 7Jameschan168 wrote:What is the great prime factor of 4^17 - 2^28
a. 2
b. 3
c. 5
d. 7
e. 11
4^17 = (2^2)^12 =2 ^34
2^34 - 2^28 = 2^28 (2^6 -1) =2 ^28 (63)
Prime factors or 63 = 7 & 3
