5∗13∗97 are factors of an expression in the question below. Factoring of the expression by 5, 13 and 97 which are prime factors should help identify a correct answer.
It's known that
3+2=5,
32+22=13 and
34+24=97. IMO, the answer must be in the form of
3n−2n with
n defined as even number.
Answer choice C is matching
3n−2n format, as
3128−2128=
(364−264)(364+264)=
(332−232)(332+232)(364−264) ...
...(3−2), where the last differential value is equal to 1
Answer is
Cgrenico wrote:
Which of the following is equivalent to:
(2+3)(22+32)(24+34)(28+38)(216+316)(232+332)(264+364)
(A) 3127+2127
(B) 3127+2127+3∗263+2∗363
(C) 3128−2128
(D) 3128+3128
(E) 5127
Source: 2021 AMC 10A Problems/Problem 10