Can someone explain the ruled used on the bold line? I do not recall how this factoring works. Thank you!
4^17 - 2^28
Understood = (2²)^17 - 2^28
Understood = 2^34 - 2^28
Do not understand the factoring here= 2^28(2^6 - 1)
Understood = 2^28(63)
Understood = 2^28(7 * 3^2)
Therefore, the greatest prime factor of 4^17 - 2^28 is 7.
The correct answer is D.
4^17 - 2^28
Understood = (2²)^17 - 2^28
Understood = 2^34 - 2^28
Do not understand the factoring here= 2^28(2^6 - 1)
Understood = 2^28(63)
Understood = 2^28(7 * 3^2)
Therefore, the greatest prime factor of 4^17 - 2^28 is 7.
The correct answer is D.
