天山07-04

[ai12345]

Q4:what is the greatest prime factor of 2^100-2^96?
A.2
B.3
C.5
D.7
E.11
答案是C
完全不會-請各位前輩幫忙解答.Thanks

[StanleyHuang]

把2^96次方提出來，原式= 2^96 * (2^4 - 1) = 2^96 * (16-1) = 2^96*3*5
所以選(C) 5